/* ───── System Design Lab ───── */

/* Tabs */
.vps-tabs {
    display: flex;
    gap: 0;
    border-bottom: 2px solid var(--bg-tertiary);
    margin-bottom: 1.5rem;
}
.vps-tab {
    padding: 0.6rem 1.25rem;
    background: none;
    border: none;
    color: var(--text-secondary, #aaa);
    font-size: 0.85rem;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: color 0.2s, border-color 0.2s;
}
.vps-tab:hover { color: var(--text-primary, #eee); }
.vps-tab.active { color: var(--accent); border-bottom-color: var(--accent); font-weight: 600; }

.vps-tab-panel.hidden { display: none; }

.vps-panel-header {
    display: flex;
    justify-content: flex-end;
    margin-bottom: 1rem;
}

.vps-section-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary, #aaa);
    margin-bottom: 0.75rem;
}

.vps-placeholder {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-muted, #888);
    font-size: 0.85rem;
}

/* LB card icon gradient */
.vps-card-icon--lb {
    background: linear-gradient(135deg, var(--success), color-mix(in srgb, var(--success) 75%, #000)) !important;
}

/* Target list on LB detail */
.vps-target-row {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    margin-bottom: 0.5rem;
}
.vps-target-name { font-weight: 600; color: var(--text-primary, #e5e5e5); flex: 1; }
.vps-target-weight { font-size: 0.75rem; color: var(--text-muted, #888); font-family: monospace; }
.vps-target-health { width: 8px; height: 8px; border-radius: 50%; background: var(--success); flex-shrink: 0; }
.vps-target-health--unhealthy { background: var(--error); }

/* Live URL display */
.vps-live-url {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1rem;
    background: var(--bg-secondary, #111);
    border: 1px solid var(--border);
    border-radius: 8px;
    margin-bottom: 1.5rem;
}
.vps-live-url a { color: var(--accent); text-decoration: none; font-family: monospace; font-size: 0.9rem; }
.vps-live-url a:hover { text-decoration: underline; }

/* Config grid */
.vps-config-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
}
@media (max-width: 600px) { .vps-config-grid { grid-template-columns: 1fr; } }

/* Stats row */
.vps-stats-row {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.75rem;
    margin-bottom: 1rem;
}
.vps-stat-card {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 0.75rem;
    text-align: center;
}
.vps-stat-value { font-size: 1.1rem; font-weight: 700; color: var(--text-primary, #eee); font-family: monospace; }
.vps-stat-label { font-size: 0.65rem; color: var(--text-muted, #888); margin-top: 0.2rem; }
@media (max-width: 600px) { .vps-stats-row { grid-template-columns: repeat(2, 1fr); } }

/* Distribution bars */
.vps-dist-row { display: flex; align-items: center; gap: 0.75rem; margin-bottom: 0.5rem; }
.vps-dist-label { font-size: 0.8rem; color: var(--text-muted, #888); min-width: 100px; }
.vps-dist-track { flex: 1; height: 8px; background: var(--border); border-radius: 4px; overflow: hidden; }
.vps-dist-bar { height: 100%; border-radius: 4px; background: var(--accent); transition: width 0.3s; }
.vps-dist-value { font-size: 0.8rem; color: var(--text-secondary, #aaa); min-width: 40px; text-align: right; font-family: monospace; }

/* Section divider */
.vps-section { margin-bottom: 1.5rem; }

/* Help button + modal */
.vps-help-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 16px; height: 16px;
    border-radius: 50%;
    background: var(--border);
    color: var(--text-muted, #888);
    font-size: 0.6rem;
    font-weight: 700;
    cursor: pointer;
    border: none;
    vertical-align: middle;
    margin-left: 0.3rem;
    transition: background 0.15s, color 0.15s;
}
.vps-help-btn:hover { background: var(--accent); color: #fff; }
.vps-help-modal-body {
    font-size: 0.85rem;
    color: var(--text-secondary, #aaa);
    line-height: 1.7;
    max-height: 60vh;
    overflow-y: auto;
    padding-right: 0.5rem;
}
.vps-help-modal-body h3 { font-size: 0.95rem; color: var(--text-primary, #eee); margin: 1.25rem 0 0.4rem; }
.vps-help-modal-body h3:first-child { margin-top: 0; }
.vps-help-modal-body p { margin-bottom: 0.75rem; }
.vps-help-modal-body code {
    background: var(--bg-secondary, #12122a);
    padding: 0.15rem 0.45rem;
    border-radius: 3px;
    font-size: 0.8rem;
    border: 1px solid var(--bg-tertiary);
}
.vps-help-modal-body ul, .vps-help-modal-body ol { margin: 0.3rem 0 0.75rem 1.2rem; }
.vps-help-modal-body li { margin-bottom: 0.35rem; }
.vps-help-modal-body .help-term { color: var(--accent); font-weight: 600; }

/* Guide link */
.vps-guide-link {
    font-size: 0.8rem;
    color: var(--text-muted, #888);
    text-decoration: none;
    transition: color 0.15s;
}
.vps-guide-link:hover { color: var(--accent); }

/* Getting started guide (used in modal and standalone page) */
.guide-content {
    font-size: 0.85rem;
    line-height: 1.8;
    color: var(--text-secondary, #aaa);
}
.guide-content h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary, #eee);
    margin: 0 0 0.75rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--bg-tertiary);
}
.guide-content h2 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--accent);
    margin: 2.5rem 0 0.75rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--bg-tertiary);
}
.guide-content h2:first-of-type { border-top: none; padding-top: 0; margin-top: 1.5rem; }
.guide-content h3 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary, #eee);
    margin: 1.5rem 0 0.5rem;
}
.guide-content p {
    margin-bottom: 0.85rem;
}
.guide-content ul, .guide-content ol {
    margin: 0.5rem 0 1rem 1.5rem;
    line-height: 1.8;
}
.guide-content li {
    margin-bottom: 0.4rem;
    padding-left: 0.25rem;
}
.guide-content code {
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    padding: 0.15rem 0.45rem;
    border-radius: 3px;
    font-size: 0.78rem;
    white-space: nowrap;
}
.guide-content pre {
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 1rem 1.25rem;
    font-size: 0.78rem;
    overflow-x: auto;
    margin: 0.75rem 0 1.25rem;
    line-height: 1.7;
    color: var(--text-primary, #eee);
}
.guide-content pre code {
    background: none;
    border: none;
    padding: 0;
    white-space: pre;
}
.guide-content a { color: var(--accent); text-decoration: none; }
.guide-content a:hover { text-decoration: underline; }
.guide-content strong { color: var(--text-primary, #eee); }

.guide-step {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 1rem 1.25rem;
    margin: 1rem 0 1.25rem;
    border-left: 3px solid var(--accent);
}
.guide-step ol, .guide-step ul {
    margin: 0.4rem 0 0.25rem 1.25rem;
}
.guide-step li {
    margin-bottom: 0.3rem;
}
.guide-step-num {
    font-weight: 700;
    color: var(--accent);
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.4rem;
}

.guide-tip {
    background: color-mix(in srgb, var(--accent) 6%, transparent);
    border: 1px solid color-mix(in srgb, var(--accent) 15%, transparent);
    border-radius: 8px;
    padding: 0.85rem 1.1rem;
    font-size: 0.82rem;
    color: var(--text-secondary, #aaa);
    margin: 1rem 0 1.25rem;
    line-height: 1.7;
}
.guide-tip strong { color: var(--accent); }

.guide-nav {
    display: flex;
    gap: 0.4rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}
.guide-nav a {
    font-size: 0.72rem;
    color: var(--text-muted, #888);
    text-decoration: none;
    padding: 0.3rem 0.6rem;
    border: 1px solid var(--bg-tertiary);
    border-radius: 4px;
    transition: color 0.15s, border-color 0.15s;
}
.guide-nav a:hover { color: var(--accent); border-color: var(--accent); }

.guide-overview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 0.75rem;
    margin: 1rem 0 1.25rem;
}
.guide-overview-card {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 0.85rem 1rem;
}
.guide-overview-card p {
    margin: 0;
    font-size: 0.8rem;
    line-height: 1.6;
}
.guide-overview-label {
    font-weight: 600;
    color: var(--accent);
    font-size: 0.8rem;
    margin-bottom: 0.35rem;
}

/* Card specs row */
.vps-card-specs {
    display: flex;
    gap: 0.75rem;
    font-size: 0.65rem;
    color: var(--text-muted, #888);
    font-family: monospace;
    padding-top: 0.5rem;
    margin-top: 0.5rem;
    border-top: 1px solid var(--bg-tertiary);
}

/* Dashboard layout */
.vps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1rem;
    margin-top: 1.5rem;
}

/* Server card */
.vps-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.25rem;
    cursor: pointer;
    transition: border-color 0.2s, transform 0.15s;
    position: relative;
}
.vps-card:hover {
    border-color: var(--accent, var(--accent));
    transform: translateY(-2px);
}

.vps-card-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}
.vps-card-icon {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--accent), color-mix(in srgb, var(--accent) 75%, #000));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    flex-shrink: 0;
    color: #fff;
}
.vps-card-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
}
.vps-card-hostname {
    font-size: 0.8rem;
    color: var(--text-muted, #888);
    font-family: monospace;
}

.vps-card-meta {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    margin-top: 0.5rem;
}
.vps-card-meta-item {
    font-size: 0.8rem;
    color: var(--text-muted, #888);
}
.vps-card-meta-item strong {
    color: var(--text-secondary, #aaa);
}

/* Status badge */
.vps-status {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    font-size: 0.75rem;
    font-weight: 500;
    padding: 2px 8px;
    border-radius: 99px;
}
.vps-status-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
}
.vps-status--running .vps-status-dot { background: var(--success); }
.vps-status--running { color: var(--success); background: rgba(34, 197, 94, 0.1); }
.vps-status--stopped .vps-status-dot { background: var(--error); }
.vps-status--stopped { color: var(--error); background: rgba(239, 68, 68, 0.1); }

/* Empty state */
.vps-empty {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-muted, #888);
}
.vps-empty-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
    color: var(--text-muted, #888);
}
.vps-empty h3 {
    color: var(--text-primary, #e5e5e5);
    margin-bottom: 0.5rem;
}

/* Page header with action */
.vps-page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 0.5rem;
}
.vps-page-header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary, #e5e5e5);
}
.vps-page-header .vps-subtitle {
    font-size: 0.9rem;
    color: var(--text-muted, #888);
    margin-top: 0.25rem;
}

/* Server detail: info panel */
.vps-info-bar {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    padding: 1rem 1.25rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 10px;
    margin-bottom: 1.5rem;
}
.vps-info-item {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}
.vps-info-label {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted, #888);
}
.vps-info-value {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary, #e5e5e5);
}

/* Site list on server detail */
.vps-sites-list {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 1rem;
}
.vps-site-row {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.75rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    transition: border-color 0.2s;
}
.vps-site-row:hover {
    border-color: var(--accent, var(--accent));
}
.vps-site-name {
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
    flex: 1;
}
.vps-site-slug {
    font-family: monospace;
    font-size: 0.8rem;
    color: var(--text-muted, #888);
}
.vps-site-meta {
    font-size: 0.8rem;
    color: var(--text-muted, #888);
    display: flex;
    gap: 1rem;
}

/* Services section */
.vps-services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 0.75rem;
}
.vps-svc-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.75rem 1rem;
    transition: border-color 0.15s;
}
.vps-svc-card:hover {
    border-color: var(--bg-hover);
}
.vps-svc--running { border-left: 3px solid var(--success); }
.vps-svc--stopped { border-left: 3px solid var(--error); }
.vps-svc--not-installed { border-left: 3px solid #555; opacity: 0.6; }
.vps-svc-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 0.4rem;
}
.vps-svc-dot {
    width: 8px; height: 8px;
    border-radius: 50%;
    flex-shrink: 0;
}
.vps-svc-dot--green { background: var(--success); box-shadow: 0 0 4px rgba(34,197,94,0.4); }
.vps-svc-dot--red { background: var(--error); }
.vps-svc-dot--gray { background: #555; }
.vps-svc-name {
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-primary, #e5e5e5);
}
.vps-svc-version {
    font-size: 0.75rem;
    color: var(--text-muted, #888);
    margin-left: auto;
}
.vps-svc-footer {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
}
.vps-svc-status {
    color: var(--text-muted, #888);
}
.vps-svc-badge {
    font-size: 0.7rem;
    padding: 1px 6px;
    border-radius: 3px;
    font-weight: 500;
}
.vps-svc-badge--enabled {
    background: rgba(34,197,94,0.15);
    color: var(--success);
}
.vps-svc-badge--disabled {
    background: rgba(239,68,68,0.1);
    color: var(--error);
}

/* Guide modal */
.vps-guide-backdrop {
    position: fixed;
    inset: 0;
    z-index: 9998;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.6);
    backdrop-filter: blur(2px);
}
.vps-guide-backdrop.hidden { display: none; }
.vps-guide-modal {
    width: min(820px, 92vw);
    height: 80vh;
    display: flex;
    flex-direction: column;
    background: var(--bg-primary, #0f0f1a);
    border: 1px solid #2a2a2a;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}
.vps-guide-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 1rem;
    background: #111;
    border-bottom: 1px solid #2a2a2a;
    flex-shrink: 0;
}
.vps-guide-modal-header span {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
}
.vps-guide-modal-header .btn {
    font-size: 0.8rem;
    padding: 0.15rem 0.5rem;
}
#guide-modal-close {
    font-size: 1.2rem;
    line-height: 1;
}
.vps-guide-iframe {
    flex: 1;
    border: none;
    width: 100%;
    scrollbar-width: thin;
    scrollbar-color: var(--border, #333) transparent;
}
.vps-guide-iframe::-webkit-scrollbar { width: 6px; }
.vps-guide-iframe::-webkit-scrollbar-track { background: transparent; }
.vps-guide-iframe::-webkit-scrollbar-thumb { background: var(--border, #333); border-radius: 3px; }
.vps-guide-iframe::-webkit-scrollbar-thumb:hover { background: var(--text-muted, #888); }

#gs-body {
    scrollbar-width: thin;
    scrollbar-color: var(--border, #333) transparent;
}
#gs-body::-webkit-scrollbar { width: 6px; }
#gs-body::-webkit-scrollbar-track { background: transparent; }
#gs-body::-webkit-scrollbar-thumb { background: var(--border, #333); border-radius: 3px; }
#gs-body::-webkit-scrollbar-thumb:hover { background: var(--text-muted, #888); }

/* Terminal modal */
.vps-terminal-backdrop {
    position: fixed;
    inset: 0;
    z-index: 9999;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0,0,0,0.6);
    backdrop-filter: blur(2px);
}
.vps-terminal-backdrop.hidden { display: none; }
.vps-terminal-modal {
    width: min(1100px, 92vw);
    height: 70vh;
    display: flex;
    flex-direction: column;
    background: #0a0a0a;
    border: 1px solid #2a2a2a;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}
.vps-terminal-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 1rem;
    background: #111;
    border-bottom: 1px solid #2a2a2a;
    flex-shrink: 0;
}
.vps-terminal-modal-header span {
    font-family: monospace;
    font-size: 0.85rem;
    color: var(--text-muted, #888);
}
.vps-terminal-modal-header .btn {
    font-size: 0.8rem;
    padding: 0.15rem 0.5rem;
}
#terminal-modal-close {
    font-size: 1.2rem;
    line-height: 1;
}
.vps-terminal-iframe {
    flex: 1;
    border: none;
    width: 100%;
    background: #0a0a0a;
}

/* Context menu */
.vps-context-menu {
    position: fixed;
    z-index: 9999;
    background: var(--bg-secondary, #1e1e2e);
    border: 1px solid var(--border, #333);
    border-radius: 6px;
    padding: 0.25rem 0;
    min-width: 140px;
    box-shadow: 0 4px 16px rgba(0,0,0,0.4);
}
.vps-context-item {
    display: block;
    width: 100%;
    padding: 0.5rem 0.75rem;
    text-align: left;
    background: none;
    border: none;
    color: var(--text-primary, #e5e5e5);
    font-size: 0.85rem;
    cursor: pointer;
}
.vps-context-item:hover {
    background: var(--bg-tertiary, #2a2a3e);
}
.vps-context-danger {
    color: var(--error);
}
.vps-context-danger:hover {
    background: rgba(239, 68, 68, 0.1);
}

/* Published badge */
.vps-badge {
    font-size: 0.7rem;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 0.03em;
}
.vps-badge--published {
    background: rgba(34, 197, 94, 0.15);
    color: var(--success);
}
.vps-badge--draft {
    background: rgba(234, 179, 8, 0.15);
    color: var(--warning);
}

/* ───── Site Editor ───── */
#site-editor {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 48px);
    overflow: hidden;
}

.vps-editor-layout {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 0;
    flex: 1;
    min-height: 0;
}

.vps-editor-toolbar {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
    flex-wrap: wrap;
}
.vps-editor-toolbar .vps-site-title {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-primary, #e5e5e5);
    margin-right: auto;
}
.vps-editor-toolbar .vps-site-url {
    font-family: monospace;
    font-size: 0.8rem;
    color: var(--text-muted, #888);
    margin-right: 1rem;
}

/* File tree sidebar */
.vps-file-tree {
    background: var(--bg-secondary);
    border-right: 1px solid var(--border);
    overflow-y: auto;
    padding: 0.5rem 0;
}
.vps-file-tree-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.5rem 0.75rem;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted, #888);
}
.vps-file-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.35rem 0.75rem;
    cursor: pointer;
    font-size: 0.85rem;
    color: var(--text-secondary, #aaa);
    transition: background 0.1s;
}
.vps-file-item:hover {
    background: var(--bg-hover);
}
.vps-file-item.active {
    background: var(--accent-light);
    color: var(--accent, var(--accent));
}
/* Delete, visible rather than hidden behind a right-click. Dim until the row
   or the button itself is under the pointer, so a list of files still reads as
   a list of files. Always present, because a touch screen has no hover. */
.vps-file-name { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.vps-file-act {
    flex: none;
    border: 0;
    background: transparent;
    color: inherit;
    opacity: 0.4;
    cursor: pointer;
    font-size: 1rem;
    line-height: 1;
    padding: 0 0.25rem;
    border-radius: 4px;
}
.vps-file-ren { margin-left: auto; font-size: 0.8rem; }
.vps-file-item:hover .vps-file-act { opacity: 0.75; }
.vps-file-act:hover,
.vps-file-act:focus-visible {
    opacity: 1;
    background: var(--bg-tertiary, rgba(255,255,255,0.06));
}
.vps-file-del:hover,
.vps-file-del:focus-visible { color: var(--danger, #ef4444); }

.vps-file-icon {
    font-size: 0.8rem;
    opacity: 0.7;
    width: 16px;
    text-align: center;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

/* Editor pane */
.vps-editor-pane {
    overflow: hidden;
    position: relative;
}
.vps-editor-pane .CodeMirror,
.vps-editor-pane .cm-editor {
    height: 100%;
    font-size: 14px;
}
.vps-editor-pane textarea {
    width: 100%;
    height: 100%;
    background: #0d1117;
    color: #e5e5e5;
    border: none;
    padding: 1rem;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 14px;
    line-height: 1.6;
    resize: none;
    outline: none;
    tab-size: 2;
}

/* Editor main wrapper (editor + console) */
.vps-editor-main {
    display: flex;
    flex-direction: column;
    overflow: hidden;
    min-height: 0;
}
.vps-editor-main .vps-editor-pane {
    flex: 1;
    min-height: 0;
}

/* Toolbar separator */
.vps-toolbar-sep {
    width: 1px;
    height: 20px;
    background: var(--border);
    margin: 0 0.25rem;
}

/* ServerScript toolbar buttons: hidden by default, shown when .server.* file is active */
.ss-toolbar-btn {
    display: none;
    color: var(--text-muted, #888);
    font-size: 0.8rem;
}
.ss-toolbar-btn.visible {
    display: inline-flex;
}
.ss-toolbar-btn.ss-active {
    color: var(--success);
    font-weight: 600;
}

/* Console output panel */
.vps-console-panel {
    border-top: 1px solid var(--border);
    background: #0a0e14;
    display: flex;
    flex-direction: column;
    max-height: 220px;
    min-height: 120px;
    flex-shrink: 0;
}
.vps-console-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.35rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--text-muted, #888);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
}
.vps-console-status {
    font-size: 0.7rem;
    font-weight: 400;
    text-transform: none;
    letter-spacing: 0;
    margin-right: 0.5rem;
}
.vps-console-body {
    overflow-y: auto;
    padding: 0.5rem 0.75rem;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 0.8rem;
    line-height: 1.5;
    color: #c5c8c6;
    flex: 1;
    min-height: 0;
}
.vps-console-line {
    padding: 1px 0;
    white-space: pre-wrap;
    word-break: break-all;
}
.vps-console-line.log { color: #c5c8c6; }
.vps-console-line.warn { color: var(--warning); }
.vps-console-line.error { color: var(--error); }
.vps-console-line.info { color: var(--accent); }
.vps-console-line.system { color: var(--text-muted, #888); font-style: italic; }
.vps-console-line.response-info {
    color: var(--success);
    border-bottom: 1px solid var(--bg-tertiary);
    padding-bottom: 4px;
    margin-bottom: 4px;
}

/* Quick Reference panel */
.vps-ref-panel {
    position: fixed;
    top: 48px;
    right: 0;
    bottom: 0;
    width: 340px;
    background: var(--bg-secondary);
    border-left: 1px solid var(--border);
    z-index: 100;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    box-shadow: -4px 0 16px rgba(0,0,0,0.3);
}
.vps-ref-panel.hidden {
    display: none;
}
.vps-ref-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
}
.vps-ref-body {
    overflow-y: auto;
    padding: 0.75rem 1rem;
    flex: 1;
}
.vps-ref-section {
    margin-bottom: 1rem;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--bg-tertiary);
}
.vps-ref-section:last-child {
    border-bottom: none;
}
.vps-ref-section h3 {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent, var(--accent));
    margin-bottom: 0.4rem;
}
.vps-ref-section code {
    font-size: 0.75rem;
    background: rgba(255,255,255,0.05);
    padding: 1px 4px;
    border-radius: 3px;
    color: #e5e5e5;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
}
.vps-ref-section small {
    font-size: 0.7rem;
    color: var(--text-muted, #888);
}

/* Template selector in Create Site modal */
.vps-template-options {
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    max-height: 200px;
    overflow-y: auto;
}
.vps-template-option {
    display: flex;
    align-items: flex-start;
    gap: 0.5rem;
    padding: 0.5rem 0.65rem;
    border: 1px solid var(--border);
    border-radius: 6px;
    cursor: pointer;
    transition: border-color 0.2s;
}
.vps-template-option:hover {
    border-color: var(--accent, var(--accent));
}
.vps-template-option.selected {
    border-color: var(--accent, var(--accent));
    background: color-mix(in srgb, var(--accent) 8%, transparent);
}
.vps-template-option input[type="radio"] {
    margin-top: 3px;
    accent-color: var(--accent, var(--accent));
}
.vps-template-option strong {
    display: block;
    font-size: 0.85rem;
    color: var(--text-primary, #e5e5e5);
}
.vps-template-option small {
    display: block;
    font-size: 0.75rem;
    color: var(--text-muted, #888);
    margin-top: 1px;
}

/* Analytics panel */
.vps-analytics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}
.vps-stat-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem;
    text-align: center;
}
.vps-stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary, #e5e5e5);
}
.vps-stat-label {
    font-size: 0.75rem;
    color: var(--text-muted, #888);
    margin-top: 0.25rem;
}

/* Tab bar */
.vps-tabs {
    display: flex;
    gap: 0;
    border-bottom: 1px solid var(--border);
    margin-bottom: 1.5rem;
}
.vps-tab {
    padding: 0.6rem 1.25rem;
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-muted, #888);
    cursor: pointer;
    border-bottom: 2px solid transparent;
    transition: color 0.2s, border-color 0.2s;
    background: none;
    border-top: none;
    border-left: none;
    border-right: none;
}
.vps-tab:hover {
    color: var(--text-primary, #e5e5e5);
}
.vps-tab.active {
    color: var(--accent, var(--accent));
    border-bottom-color: var(--accent, var(--accent));
}

/* Modal */
.vps-modal-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
    display: flex;
    align-items: flex-start;
    justify-content: center;
    z-index: 1000;
    overflow-y: auto;
    padding: 3rem 1rem;
}
.vps-modal {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 1.5rem;
    width: 90%;
    max-width: 440px;
    margin: auto;
}
.vps-modal h2 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--text-primary, #e5e5e5);
}
.vps-modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
    margin-top: 1.25rem;
}

/* Form elements (inherit from main where possible) */
.vps-input {
    width: 100%;
    padding: 0.6rem 0.75rem;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-primary, #e5e5e5);
    font-size: 0.9rem;
    outline: none;
    transition: border-color 0.2s;
}
.vps-input:focus {
    border-color: var(--accent, var(--accent));
}
.vps-label {
    display: block;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary, #aaa);
    margin-bottom: 0.35rem;
}
.vps-form-group {
    margin-bottom: 1rem;
}

/* ═══ Database Browser ═══ */

.vps-db-query-section {
    margin-top: 1rem;
}
.vps-db-query-section textarea {
    width: 100%;
    background: var(--bg-secondary);
    color: var(--text-primary, #e4e6f0);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.5rem;
    font-size: 0.85rem;
}

.vps-db-results {
    overflow-x: auto;
}

.vps-db-data-table,
.vps-db-schema-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.8rem;
    font-family: monospace;
}
.vps-db-data-table th,
.vps-db-schema-table th {
    background: var(--bg-secondary);
    color: var(--text-muted, #888);
    padding: 0.35rem 0.5rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}
.vps-db-data-table td,
.vps-db-schema-table td {
    padding: 0.3rem 0.5rem;
    border-bottom: 1px solid var(--bg-tertiary);
    max-width: 250px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.vps-db-data-table tr:nth-child(even) {
    background: var(--bg-secondary);
}
.vps-db-data-table tr:hover {
    background: var(--bg-hover, #252545);
}

.vps-db-schema {
    margin-bottom: 0.5rem;
}
.vps-db-schema details summary {
    user-select: none;
}

.vps-db-pagination {
    margin-top: 0.5rem;
}

/* ═══ Analytics Dashboard ═══ */

.vps-analytics-header { display:flex; align-items:center; justify-content:space-between; flex-wrap:wrap; gap:1rem; margin-bottom:1.5rem }
.vps-range-selector { display:flex; gap:0; border:1px solid var(--border); border-radius:6px; overflow:hidden }
.vps-range-btn { padding:0.4rem 1rem; font-size:0.8rem; background:transparent; color:var(--text-muted,#888); border:none; cursor:pointer; transition:all 0.2s }
.vps-range-btn:hover { color:var(--text-primary,#e5e5e5) }
.vps-range-btn.active { background:var(--accent,var(--accent)); color:#fff }
.vps-chart-container { position:relative; height:280px; margin-bottom:1.5rem; background:var(--bg-secondary); border:1px solid var(--border); border-radius:10px; padding:1rem }
.vps-chart-row { display:grid; grid-template-columns:1fr 1fr; gap:1rem; margin-bottom:1.5rem }
.vps-chart-card { background:var(--bg-secondary); border:1px solid var(--border); border-radius:10px; padding:1rem }
.vps-chart-card h3 { font-size:0.85rem; color:var(--text-muted,#888); margin-bottom:0.75rem }
.vps-live-dot { display:inline-block; width:8px; height:8px; border-radius:50%; background:var(--success); margin-right:0.35rem; animation:vps-pulse 2s infinite }
@keyframes vps-pulse { 0%,100%{opacity:1} 50%{opacity:0.4} }
.vps-events-list { max-height:300px; overflow-y:auto }
.vps-event-row { padding:0.4rem 0; border-bottom:1px solid var(--bg-tertiary); font-size:0.8rem; display:flex; gap:0.75rem }
.vps-event-path { color:var(--text-primary,#e5e5e5); font-family:monospace; min-width:100px }
.vps-event-ua { color:var(--text-muted,#888); flex:1 }
.vps-event-time { color:var(--text-muted,#888); white-space:nowrap }

/* ═══ System Design Lab ═══ */

.sd-toolbar {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--bg-tertiary);
}
.sd-toolbar-title { font-weight: 600; font-size: 1rem; }
.sd-toolbar .vps-badge { font-size: 0.65rem; }
.sd-toolbar-cost { font-size: 0.75rem; color: var(--text-muted, #888); font-family: monospace; }

/* Tabs */
.sd-tabs {
    display: flex;
    gap: 0;
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--bg-tertiary);
    padding: 0 1rem;
}
.sd-tab {
    padding: 0.6rem 1.2rem;
    background: none;
    border: none;
    color: var(--text-secondary, #aaa);
    font-size: 0.8rem;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: color 0.2s, border-color 0.2s;
}
.sd-tab:hover { color: var(--text-primary, #eee); }
.sd-tab.active { color: var(--accent); border-bottom-color: var(--accent); font-weight: 600; }

.sd-tab-panel { display: none; }
.sd-tab-panel.active { display: block; }

/* Architecture tab layout */
.sd-arch-layout {
    display: grid;
    grid-template-columns: 300px 1fr;
    height: calc(100vh - 140px);
    overflow: hidden;
}

.sd-arch-controls {
    background: var(--bg-secondary);
    border-right: 1px solid var(--border);
    overflow-y: auto;
    padding: 0.75rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.sd-arch-diagram {
    position: relative;
    background: var(--bg-secondary, #12122a);
    overflow: hidden;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
    flex-wrap: wrap;
}
.sd-arch-diagram svg {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
}
.sd-connection { stroke: var(--border); stroke-width: 1.5; }

/* Components */
.sd-comp {
    position: absolute;
    padding: 0.35rem 0.75rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.7rem;
    text-align: center;
    z-index: 1;
    min-width: 80px;
    white-space: nowrap;
}
.sd-comp-name { font-weight: 600; }
.sd-comp-sub { font-size: 0.6rem; color: var(--text-muted, #888); margin-top: 1px; }
.sd-comp-cloud { border-color: var(--accent); }
.sd-comp-lb { border-color: var(--warning); }
.sd-comp-server { border-color: var(--success); }
.sd-comp-cache { border-color: #ec4899; }
.sd-comp-db { border-color: #8b5cf6; }
.sd-comp-db-replica { border-color: #8b5cf6; border-style: dashed; opacity: 0.8; }
.sd-comp-autoscale { border-color: #06b6d4; border-style: dashed; font-style: italic; }
.sd-inactive { opacity: 0.3; }

/* Shared controls */
.sd-section {
    background: var(--bg-secondary, #12122a);
    border-radius: 6px;
    padding: 0.65rem 0.75rem;
}
.sd-section-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-primary, #eee);
    margin-bottom: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.4rem;
}
.sd-tooltip {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 14px; height: 14px;
    border-radius: 50%;
    background: var(--border);
    color: var(--text-muted, #888);
    font-size: 0.55rem;
    cursor: help;
    font-weight: 700;
    position: relative;
}
.sd-tooltip::after {
    content: attr(data-tip);
    position: absolute;
    left: 50%;
    bottom: calc(100% + 8px);
    transform: translateX(-50%);
    background: var(--bg-secondary);
    border: 1px solid #3a3a5a;
    color: #ccc;
    font-size: 0.7rem;
    font-weight: 400;
    line-height: 1.4;
    padding: 0.5rem 0.65rem;
    border-radius: 6px;
    width: 220px;
    white-space: normal;
    pointer-events: none;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.15s, visibility 0.15s;
    z-index: 100;
    box-shadow: 0 4px 12px rgba(0,0,0,0.4);
}
.sd-tooltip:hover::after {
    opacity: 1;
    visibility: visible;
}
.sd-tooltip-below::after {
    bottom: auto;
    top: calc(100% + 8px);
}
.sd-control {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    margin-bottom: 0.4rem;
    font-size: 0.75rem;
    color: var(--text-secondary, #aaa);
}
.sd-control label { font-size: 0.7rem; min-width: 60px; }
.sd-control select {
    flex: 1;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-primary, #eee);
    border-radius: 4px;
    padding: 0.25rem 0.4rem;
    font-size: 0.7rem;
}
.sd-control input[type="range"] {
    flex: 1;
    accent-color: var(--accent);
}
.sd-control textarea {
    flex: 1;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-primary, #eee);
    border-radius: 4px;
    padding: 0.3rem 0.4rem;
    font-size: 0.7rem;
    font-family: monospace;
    resize: vertical;
}
.sd-sub-control { padding-left: 0.75rem; }
.sd-hint { font-size: 0.65rem; color: var(--text-muted, #888); margin-top: 0.15rem; }

/* Instance +/- control */
.sd-instance-control {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.sd-instance-control button {
    width: 24px; height: 24px;
    border-radius: 4px;
    border: 1px solid var(--border);
    background: var(--bg-secondary);
    color: var(--text-primary, #eee);
    font-size: 0.9rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}
.sd-instance-control button:hover { border-color: var(--accent); }
.sd-instance-control button:disabled { opacity: 0.3; cursor: default; }
.sd-instance-control.sd-small button { width: 20px; height: 20px; font-size: 0.75rem; }

/* Toggle */
.sd-toggle { display: flex; align-items: center; gap: 0.5rem; cursor: pointer; }
.sd-toggle input { display: none; }
.sd-toggle-track {
    width: 32px; height: 18px;
    background: var(--border);
    border-radius: 9px;
    position: relative;
    transition: background 0.2s;
}
.sd-toggle-track::after {
    content: '';
    position: absolute;
    top: 2px; left: 2px;
    width: 14px; height: 14px;
    border-radius: 50%;
    background: #888;
    transition: transform 0.2s, background 0.2s;
}
.sd-toggle input:checked + .sd-toggle-track { background: var(--accent); }
.sd-toggle input:checked + .sd-toggle-track::after { transform: translateX(14px); background: #fff; }
.sd-toggle-label { font-size: 0.7rem; color: var(--text-secondary, #aaa); }

/* Load Test tab */
.sd-lt-layout {
    display: grid;
    grid-template-columns: 320px 1fr;
    height: calc(100vh - 140px);
    overflow: hidden;
}
.sd-lt-config {
    background: var(--bg-secondary);
    border-right: 1px solid var(--border);
    padding: 0.75rem;
    overflow-y: auto;
}
.sd-lt-results {
    padding: 1.25rem;
    overflow-y: auto;
}
.sd-lt-progress {
    height: 4px;
    background: var(--border);
    border-radius: 2px;
    margin-bottom: 1rem;
    overflow: hidden;
}
.sd-lt-progress-bar {
    height: 100%;
    background: var(--accent);
    border-radius: 2px;
    transition: width 0.3s;
}
.sd-lt-status {
    text-align: center;
    color: var(--text-secondary, #aaa);
    font-size: 0.85rem;
}
.sd-empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-muted, #888);
    font-size: 0.85rem;
}

/* Stats grid */
.sd-stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.75rem;
    margin-bottom: 1rem;
}
.sd-stat-card {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 0.75rem;
    text-align: center;
}
.sd-stat-value {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary, #eee);
    font-family: monospace;
}
.sd-stat-label { font-size: 0.65rem; color: var(--text-muted, #888); margin-top: 0.25rem; }
.sd-stat-detail {
    display: flex;
    gap: 1.5rem;
    font-size: 0.7rem;
    color: var(--text-secondary, #aaa);
    margin-bottom: 1rem;
    font-family: monospace;
}
.sd-chart-container { height: 200px; margin-top: 1rem; }

/* Results & Projections tab */
.sd-results-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    height: calc(100vh - 140px);
    overflow: hidden;
}
.sd-results-sidebar {
    background: var(--bg-secondary);
    border-right: 1px solid var(--border);
    padding: 0.75rem;
    overflow-y: auto;
}
.sd-results-main {
    padding: 1.25rem;
    overflow-y: auto;
}

/* Test history list */
.sd-test-history { display: flex; flex-direction: column; gap: 0.35rem; }
.sd-test-item {
    padding: 0.5rem 0.6rem;
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    border-radius: 6px;
    cursor: pointer;
    transition: border-color 0.2s;
    border-left: 3px solid var(--success);
}
.sd-test-item:hover { border-color: var(--accent); }
.sd-test-item.sd-test-selected { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 8%, transparent); }
.sd-test-item.sd-test-fail { border-left-color: var(--error); }
.sd-test-item-top { display: flex; justify-content: space-between; font-size: 0.75rem; font-weight: 600; }
.sd-test-item-bottom { display: flex; gap: 0.75rem; font-size: 0.65rem; color: var(--text-muted, #888); margin-top: 0.2rem; }
.sd-test-rps { color: var(--accent); }
.sd-test-time { color: var(--text-muted, #888); }

/* Comparison cards */
.sd-compare-grid {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 1rem;
    align-items: center;
    margin-bottom: 1.5rem;
}
.sd-compare-card {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 1rem;
}
.sd-compare-header {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 0.75rem;
    color: var(--text-muted, #888);
}
.sd-compare-baseline .sd-compare-header { color: #9ca3af; }
.sd-compare-projected .sd-compare-header { color: var(--accent); }
.sd-compare-projected { border-color: color-mix(in srgb, var(--accent) 30%, transparent); }
.sd-compare-metric {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    padding: 0.3rem 0;
    border-bottom: 1px solid var(--bg-tertiary);
}
.sd-compare-metric:last-child { border-bottom: none; }
.sd-compare-value { font-size: 1rem; font-weight: 700; font-family: monospace; }
.sd-compare-label { font-size: 0.65rem; color: var(--text-muted, #888); }
.sd-compare-arrow { font-size: 1.5rem; color: var(--accent); text-align: center; }

/* Multiplier badge */
.sd-multiplier {
    text-align: center;
    padding: 0.75rem;
    margin-bottom: 1.5rem;
    font-size: 0.85rem;
    color: var(--text-secondary, #aaa);
}
.sd-multiplier-value {
    font-size: 1.8rem;
    font-weight: 800;
    color: var(--success);
    font-family: monospace;
}

/* Gauges (kept from old scaling) */
.sd-gauges {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 1.5rem;
}
.sd-gauge {
    text-align: center;
    width: 80px;
}
.sd-gauge-arc {
    width: 80px; height: 40px;
    border-radius: 80px 80px 0 0;
    background: conic-gradient(
        from 180deg,
        var(--gauge-color, var(--success)) 0deg,
        var(--gauge-color, var(--success)) var(--gauge-angle, 0deg),
        var(--border) var(--gauge-angle, 0deg),
        var(--border) 180deg
    );
    position: relative;
    overflow: hidden;
}
.sd-gauge-arc::after {
    content: '';
    position: absolute;
    bottom: 0; left: 10%; right: 10%;
    height: 60%;
    background: var(--bg-primary, #0e0e1a);
    border-radius: 60px 60px 0 0;
}
.sd-gauge-value {
    font-size: 0.9rem;
    font-weight: 700;
    font-family: monospace;
    margin-top: -0.15rem;
}
.sd-gauge-label { font-size: 0.65rem; color: var(--text-muted, #888); }

/* Bottleneck & recommendations */
.sd-bottleneck {
    padding: 0.65rem 0.85rem;
    border-radius: 6px;
    font-size: 0.8rem;
    margin-bottom: 0.75rem;
    border-left: 3px solid;
}
.sd-bn-ok { background: rgba(34,197,94,0.08); border-color: var(--success); color: var(--success); }
.sd-bn-warn { background: color-mix(in srgb, var(--warning) 8%, transparent); border-color: var(--warning); color: var(--warning); }
.sd-bn-critical { background: rgba(239,68,68,0.08); border-color: var(--error); color: var(--error); }
.sd-bn-info { background: color-mix(in srgb, var(--accent) 8%, transparent); border-color: var(--accent); color: var(--accent); }
.sd-recommendations { display: flex; flex-direction: column; gap: 0.4rem; margin-bottom: 1.5rem; }
.sd-rec {
    padding: 0.5rem 0.75rem;
    border-radius: 4px;
    font-size: 0.75rem;
    background: var(--bg-secondary, #12122a);
    border-left: 3px solid;
}
.sd-rec-info { border-color: var(--accent); color: var(--text-secondary, #aaa); }
.sd-rec-warning { border-color: var(--warning); color: var(--text-secondary, #aaa); }
.sd-rec-critical { border-color: var(--error); color: var(--text-secondary, #aaa); }
.sd-rec-success { border-color: var(--success); color: var(--text-secondary, #aaa); }

/* Cost breakdown */
.sd-cost-breakdown { margin-top: 1rem; }
.sd-cost-items {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    font-size: 0.75rem;
    color: var(--text-secondary, #aaa);
    font-family: monospace;
}
.sd-cost-total { font-weight: 700; color: var(--text-primary, #eee); }

/* Mobile */
@media (max-width: 768px) {
    .sd-arch-layout, .sd-lt-layout, .sd-results-layout {
        grid-template-columns: 1fr;
        height: auto;
    }
    .sd-arch-controls, .sd-lt-config, .sd-results-sidebar {
        border-right: none;
        border-bottom: 1px solid var(--border);
        max-height: 50vh;
    }
    .sd-stats-grid { grid-template-columns: repeat(2, 1fr); }
    .sd-compare-grid { grid-template-columns: 1fr; }
    .sd-compare-arrow { transform: rotate(90deg); }
}

/* (legacy scaling classes below can be removed after full migration) */
.sd-placeholder-end { display: none; }
.scaling-toolbar-title {
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-primary, #e5e5e5);
    margin-right: auto;
}
.scaling-toolbar .vps-badge {
    margin-right: auto;
}

.scaling-section {
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.75rem;
    background: var(--bg-secondary, rgba(255,255,255,0.02));
}
.scaling-section-title {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted, #888);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.scaling-control {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}
.scaling-control:last-child {
    margin-bottom: 0;
}
.scaling-control label {
    font-size: 0.8rem;
    color: var(--text-secondary, #aaa);
    white-space: nowrap;
}
.scaling-control select,
.scaling-control input[type="number"] {
    padding: 0.3rem 0.5rem;
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 4px;
    color: var(--text-primary, #e5e5e5);
    font-size: 0.8rem;
    min-width: 0;
    width: auto;
}
.scaling-control select {
    max-width: 140px;
}

.scaling-slider-row {
    margin-bottom: 0.5rem;
}
.scaling-slider-row label {
    font-size: 0.8rem;
    color: var(--text-secondary, #aaa);
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.25rem;
}
.scaling-slider-row input[type="range"] {
    width: 100%;
    height: 6px;
    -webkit-appearance: none;
    appearance: none;
    background: var(--border);
    border-radius: 3px;
    outline: none;
}
.scaling-slider-row input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--accent, var(--accent));
    cursor: pointer;
}

.scaling-btn-row {
    display: flex;
    gap: 0.35rem;
    margin-top: 0.5rem;
}
.scaling-btn-row .btn {
    flex: 1;
    font-size: 0.75rem;
    padding: 0.35rem 0.5rem;
}

.scaling-instance-control {
    display: flex;
    align-items: center;
    gap: 0.35rem;
}
.scaling-instance-control button {
    width: 28px;
    height: 28px;
    border-radius: 4px;
    border: 1px solid var(--border);
    background: var(--bg-primary);
    color: var(--text-primary, #e5e5e5);
    font-size: 1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}
.scaling-instance-control button:hover {
    border-color: var(--accent, var(--accent));
}
.scaling-instance-control button:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}
.scaling-instance-count {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
    min-width: 24px;
    text-align: center;
}

.scaling-toggle {
    position: relative;
    width: 36px;
    height: 20px;
    flex-shrink: 0;
}
.scaling-toggle input {
    opacity: 0;
    width: 0;
    height: 0;
}
.scaling-toggle-track {
    position: absolute;
    inset: 0;
    background: var(--border);
    border-radius: 10px;
    cursor: pointer;
    transition: background 0.2s;
}
.scaling-toggle-track::after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: #fff;
    transition: transform 0.2s;
}
.scaling-toggle input:checked + .scaling-toggle-track {
    background: var(--accent, var(--accent));
}
.scaling-toggle input:checked + .scaling-toggle-track::after {
    transform: translateX(16px);
}

/* Architecture diagram */
.scaling-diagram {
    position: relative;
    min-height: 320px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1.25rem;
    overflow: hidden;
}
.scaling-diagram svg {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
}
.scaling-component {
    position: absolute;
    padding: 0.5rem 0.75rem;
    border: 2px solid var(--border);
    border-radius: 8px;
    background: var(--bg-secondary);
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
    text-align: center;
    z-index: 1;
    transition: border-color 0.3s, background 0.3s, opacity 0.3s;
    min-width: 80px;
}
.scaling-component.inactive {
    border-style: dashed;
    opacity: 0.4;
}
.scaling-component.status-green { border-color: var(--success); }
.scaling-component.status-yellow { border-color: var(--warning); }
.scaling-component.status-orange { border-color: var(--warning); }
.scaling-component.status-red { border-color: var(--error); background: rgba(239,68,68,0.1); }
.scaling-component.status-dead { border-color: var(--error); background: rgba(239,68,68,0.2); }
.scaling-component-label {
    font-size: 0.65rem;
    color: var(--text-muted, #888);
    margin-top: 0.15rem;
}
.scaling-component-value {
    font-size: 0.75rem;
    font-weight: 700;
    margin-top: 0.1rem;
}

.scaling-connection {
    stroke: var(--border);
    stroke-width: 2;
    fill: none;
    transition: stroke 0.3s;
}
.scaling-connection.active {
    stroke: var(--accent, var(--accent));
    stroke-dasharray: 6 4;
    animation: scaling-dash 0.6s linear infinite;
}
@keyframes scaling-dash {
    to { stroke-dashoffset: -10; }
}

.scaling-dot {
    r: 4;
    fill: var(--success);
    filter: drop-shadow(0 0 3px rgba(34,197,94,0.6));
}
.scaling-dot.error {
    fill: var(--error);
    filter: drop-shadow(0 0 3px rgba(239,68,68,0.6));
}

/* Resource gauges */
.scaling-gauges {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
}
.scaling-gauge {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1rem;
    text-align: center;
}
.scaling-gauge-arc {
    width: 120px;
    height: 60px;
    margin: 0 auto 0.5rem;
    position: relative;
    overflow: hidden;
}
.scaling-gauge-arc::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 120px;
    height: 120px;
    border-radius: 50%;
    background: conic-gradient(
        var(--gauge-color, var(--success)) 0deg,
        var(--gauge-color, var(--success)) var(--gauge-angle, 0deg),
        var(--border) var(--gauge-angle, 0deg),
        var(--border) 180deg,
        transparent 180deg
    );
    mask: radial-gradient(circle at center, transparent 40px, black 41px);
    -webkit-mask: radial-gradient(circle at center, transparent 40px, black 41px);
}
.scaling-gauge-value {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-primary, #e5e5e5);
}
.scaling-gauge-label {
    font-size: 0.7rem;
    color: var(--text-muted, #888);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    margin-top: 0.1rem;
}

/* Stats bar */
.scaling-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.75rem;
}
.scaling-stat {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 0.75rem;
    text-align: center;
}
.scaling-stat-value {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-primary, #e5e5e5);
}
.scaling-stat-label {
    font-size: 0.7rem;
    color: var(--text-muted, #888);
    margin-top: 0.1rem;
}

/* Event log */
.scaling-event-log {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    max-height: 180px;
    overflow-y: auto;
    flex: 1;
    min-height: 0;
}
.scaling-event-log-title {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted, #888);
    padding: 0.5rem 0.65rem 0.25rem;
    font-weight: 600;
    position: sticky;
    top: 0;
    background: var(--bg-secondary);
}
.scaling-event {
    padding: 0.25rem 0.65rem;
    font-size: 0.7rem;
    color: var(--text-secondary, #aaa);
    border-bottom: 1px solid var(--bg-tertiary);
    display: flex;
    gap: 0.5rem;
}
.scaling-event-time {
    color: var(--text-muted, #888);
    white-space: nowrap;
    font-family: monospace;
}
.scaling-event.warn { color: var(--warning); }
.scaling-event.error { color: var(--error); }
.scaling-event.info { color: var(--accent); }
.scaling-event.success { color: var(--success); }

/* ═══ System Builder ═══ */

.sys-toolbar {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--bg-tertiary);
    flex-wrap: wrap;
}
.sys-toolbar-name { font-weight: 600; font-size: 1rem; }
.sys-toolbar-site { display: flex; align-items: center; gap: 0.4rem; }
.sys-toolbar-site select {
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--border);
    color: var(--text-primary, #eee);
    border-radius: 4px;
    padding: 0.2rem 0.4rem;
    max-width: 200px;
}
.sys-live-url {
    font-size: 0.75rem;
    color: var(--accent);
    text-decoration: none;
    font-family: monospace;
}
.sys-live-url:hover { text-decoration: underline; }

/* Layout: sidebar + diagram */
.sys-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    height: calc(100vh - 220px);
    overflow: hidden;
}

.sys-sidebar {
    background: var(--bg-secondary);
    border-right: 1px solid var(--border);
    padding: 0.75rem;
    overflow-y: auto;
}

.sys-section-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-primary, #eee);
}

/* Add component buttons */
.sys-add-buttons {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}
.sys-add-btn {
    display: block;
    width: 100%;
    padding: 0.4rem 0.6rem;
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    border-radius: 5px;
    color: var(--text-secondary, #aaa);
    font-size: 0.7rem;
    cursor: pointer;
    text-align: left;
    transition: border-color 0.15s, color 0.15s;
    border-left: 3px solid transparent;
}
.sys-add-btn:hover { border-color: var(--border); color: var(--text-primary, #eee); }
.sys-add-server { border-left-color: var(--accent); }
.sys-add-lb { border-left-color: var(--warning); }
.sys-add-cache { border-left-color: #ec4899; }
.sys-add-db { border-left-color: #8b5cf6; }
.sys-add-replica { border-left-color: #06b6d4; }

/* Component cards in sidebar */
.sys-comp-card {
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    border-radius: 5px;
    padding: 0.4rem 0.6rem;
    margin-bottom: 0.3rem;
}
.sys-comp-card-header {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    font-size: 0.75rem;
}
.sys-comp-card-label { font-weight: 600; flex: 1; }
.sys-comp-delete {
    background: none;
    border: none;
    color: var(--text-muted, #888);
    font-size: 1rem;
    cursor: pointer;
    padding: 0 0.2rem;
    line-height: 1;
}
.sys-comp-delete:hover { color: var(--error); }
.sys-comp-card-detail {
    font-size: 0.65rem;
    color: var(--text-muted, #888);
    margin-top: 0.15rem;
    font-family: monospace;
}

/* Diagram area */
.sys-diagram {
    position: relative;
    background: var(--bg-secondary, #12122a);
    overflow: hidden;
}
.sys-diagram svg {
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    pointer-events: none;
}
.sys-diagram-empty {
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    color: var(--text-muted, #888);
    font-size: 0.85rem;
    text-align: center;
}
.sys-connection { stroke: var(--border); stroke-width: 1.5; }

/* Diagram nodes */
.sys-node {
    position: absolute;
    padding: 0.3rem 0.75rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    font-size: 0.7rem;
    font-weight: 600;
    text-align: center;
    z-index: 1;
    min-width: 80px;
    white-space: nowrap;
}
.sys-node-cloud { border-color: #9ca3af; color: #9ca3af; }
.sys-node-server { border-color: var(--accent); color: var(--accent); }
.sys-node-lb { border-color: var(--warning); color: var(--warning); }
.sys-node-cache { border-color: #ec4899; color: #ec4899; }
.sys-node-db { border-color: #8b5cf6; color: #8b5cf6; }
.sys-node-replica { border-color: #06b6d4; color: #06b6d4; border-style: dashed; }

/* Bottom tabs */
.sys-bottom-tabs {
    display: flex;
    gap: 0;
    background: var(--bg-secondary);
    border-top: 1px solid var(--bg-tertiary);
    border-bottom: 1px solid var(--bg-tertiary);
    padding: 0 1rem;
}
.sys-btab {
    padding: 0.4rem 1rem;
    background: none;
    border: none;
    color: var(--text-secondary, #aaa);
    font-size: 0.75rem;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -1px;
}
.sys-btab.active { color: var(--accent); border-bottom-color: var(--accent); font-weight: 600; }
.sys-btab-panel { display: none; }
.sys-btab-panel.active { display: block; }
.sys-bottom-panel {
    background: var(--bg-secondary);
    min-height: 80px;
}

/* Mobile */
@media (max-width: 768px) {
    .sys-layout { grid-template-columns: 1fr; height: auto; }
    .sys-sidebar { border-right: none; border-bottom: 1px solid var(--border); max-height: 40vh; }
    .sys-diagram { min-height: 300px; }
}

/* ═══ ServerScript Guide ═══ */

.ss-guide-layout {
    display: grid;
    grid-template-columns: 200px 1fr;
    min-height: calc(100vh - 48px);
}

.ss-guide-nav {
    position: sticky;
    top: 48px;
    height: calc(100vh - 48px);
    overflow-y: auto;
    padding: 1rem 0.75rem;
    background: var(--bg-secondary);
    border-right: 1px solid var(--border);
}
.ss-guide-nav-title {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted, #888);
    font-weight: 600;
    margin-bottom: 0.75rem;
    padding: 0 0.5rem;
}
.ss-guide-link {
    display: block;
    padding: 0.35rem 0.5rem;
    font-size: 0.8rem;
    color: var(--text-muted, #888);
    text-decoration: none;
    border-radius: 4px;
    transition: color 0.15s, background 0.15s;
    line-height: 1.3;
    margin-bottom: 1px;
}
.ss-guide-link:hover {
    color: var(--text-primary, #e5e5e5);
    background: var(--bg-hover);
}
.ss-guide-link.active {
    color: var(--accent, var(--accent));
    background: var(--accent-light);
    font-weight: 500;
}

.ss-guide-content {
    padding: 2rem 2.5rem 4rem;
    max-width: 820px;
    overflow-y: auto;
}
.ss-guide-content section {
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--bg-tertiary);
}
.ss-guide-content section:last-of-type {
    border-bottom: none;
}
.ss-guide-content h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary, #e5e5e5);
    margin-bottom: 0.75rem;
}
.ss-guide-content h2 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary, #e5e5e5);
    margin-top: 1.75rem;
    margin-bottom: 0.5rem;
}
.ss-guide-content h3 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-secondary, #aaa);
    margin-top: 1.25rem;
    margin-bottom: 0.35rem;
}
.ss-guide-content p {
    font-size: 0.9rem;
    line-height: 1.7;
    color: var(--text-secondary, #aaa);
    margin-bottom: 0.75rem;
}
.ss-guide-content ul, .ss-guide-content ol {
    font-size: 0.9rem;
    line-height: 1.7;
    color: var(--text-secondary, #aaa);
    margin-bottom: 0.75rem;
    padding-left: 1.5rem;
}
.ss-guide-content li {
    margin-bottom: 0.25rem;
}
.ss-guide-content code {
    font-size: 0.82rem;
    background: rgba(255,255,255,0.06);
    padding: 1px 5px;
    border-radius: 3px;
    color: #e5e5e5;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
}
.ss-guide-content a {
    color: var(--accent, var(--accent));
    text-decoration: none;
}
.ss-guide-content a:hover {
    text-decoration: underline;
}
.ss-guide-content strong {
    color: var(--text-primary, #e5e5e5);
}
.ss-guide-content em {
    color: var(--text-secondary, #aaa);
    font-style: italic;
}

.ss-guide-code {
    background: #0d1117;
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 1rem 1.25rem;
    margin: 0.75rem 0 1rem;
    overflow-x: auto;
}
.ss-guide-code pre {
    margin: 0;
    font-family: 'JetBrains Mono', 'Fira Code', monospace;
    font-size: 0.82rem;
    line-height: 1.6;
    color: #c9d1d9;
    white-space: pre;
}
.ss-guide-code code {
    background: none;
    padding: 0;
    font-size: 0.85rem;
    color: #c9d1d9;
}

.ss-guide-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.85rem;
    margin: 0.75rem 0 1rem;
}
.ss-guide-table th {
    text-align: left;
    padding: 0.5rem 0.75rem;
    background: var(--bg-secondary);
    color: var(--text-primary, #e5e5e5);
    font-weight: 600;
    border-bottom: 1px solid var(--border);
}
.ss-guide-table td {
    padding: 0.5rem 0.75rem;
    color: var(--text-secondary, #aaa);
    border-bottom: 1px solid var(--bg-tertiary);
    line-height: 1.5;
}

.ss-guide-difficulty {
    font-size: 0.7rem;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: 4px;
    text-transform: uppercase;
    letter-spacing: 0.03em;
    background: color-mix(in srgb, var(--accent) 15%, transparent);
    color: var(--accent, var(--accent));
    vertical-align: middle;
    margin-left: 0.5rem;
}

.ss-guide-footer {
    margin-top: 2rem;
    padding: 1.25rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    font-size: 0.85rem;
    color: var(--text-secondary, #aaa);
}
.ss-guide-footer p {
    margin: 0;
}

/* ═══ Responsive ═══ */

/* Responsive */
@media (max-width: 768px) {
    .vps-editor-layout {
        grid-template-columns: 1fr;
        grid-template-rows: auto auto 1fr;
    }
    .vps-file-tree {
        border-right: none;
        border-bottom: 1px solid var(--border);
        max-height: 150px;
    }
    .vps-grid {
        grid-template-columns: 1fr;
    }
    .vps-chart-row {
        grid-template-columns: 1fr;
    }
    .vps-analytics-grid {
        grid-template-columns: repeat(2, 1fr) !important;
    }
    .scaling-layout {
        grid-template-columns: 1fr;
        height: auto;
    }
    .scaling-sidebar {
        border-right: none;
        border-bottom: 1px solid var(--border);
        max-height: none;
        overflow-y: visible;
    }
    .scaling-main {
        overflow-y: visible;
    }
    .scaling-gauges {
        grid-template-columns: 1fr;
    }
    .scaling-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    .scaling-diagram {
        min-height: 280px;
    }
    .vps-ref-panel {
        width: 100%;
    }
    .ss-toolbar-btn {
        font-size: 0.7rem;
    }
    .ss-guide-layout {
        grid-template-columns: 1fr;
    }
    .ss-guide-nav {
        position: static;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--border);
        display: flex;
        flex-wrap: wrap;
        gap: 0.25rem;
        padding: 0.75rem;
    }
    .ss-guide-nav-title {
        width: 100%;
        margin-bottom: 0.25rem;
    }
    .ss-guide-content {
        padding: 1.5rem 1rem 3rem;
    }
}

/* ── Design Challenges ── */

.challenge-stats-bar {
    margin-bottom: 1.25rem;
}
.challenge-progress-wrap {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 0.75rem 1rem;
}
.challenge-progress-text {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}
.challenge-progress-bar {
    height: 6px;
    background: var(--bg-secondary, #12122a);
    border-radius: 3px;
    overflow: hidden;
}
.challenge-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--success), color-mix(in srgb, var(--success) 75%, #fff));
    border-radius: 3px;
    transition: width 0.5s ease;
}

.challenge-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 0.75rem;
}

.challenge-card {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 1rem;
    cursor: pointer;
    transition: border-color 0.15s, transform 0.1s;
}
.challenge-card:hover {
    border-color: var(--text-muted);
    transform: translateY(-1px);
}
.challenge-card--completed {
    opacity: 0.75;
}
.challenge-card--completed:hover {
    opacity: 1;
}

.challenge-card-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.challenge-difficulty {
    font-size: 0.65rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.15rem 0.5rem;
    border-radius: 4px;
}

.challenge-xp {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--warning);
}

.challenge-card-title {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.35rem;
}

.challenge-card-desc {
    font-size: 0.78rem;
    color: var(--text-muted);
    line-height: 1.4;
    margin-bottom: 0.75rem;
}

.challenge-card-bottom {
    display: flex;
    align-items: center;
}

.challenge-status {
    font-size: 0.75rem;
    color: var(--text-muted);
}
.challenge-status--completed {
    color: var(--success);
    display: flex;
    align-items: center;
    gap: 0.3rem;
    font-weight: 600;
}
.challenge-status--progress {
    color: var(--warning);
    font-weight: 500;
}

/* Challenge detail modal */
.challenge-detail-modal {
    max-height: 85vh;
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

.challenge-checklist {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    border-radius: 8px;
    padding: 0.75rem;
}

.challenge-check-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-secondary);
    padding: 0.25rem 0;
}
.challenge-check-item svg {
    flex-shrink: 0;
}
.challenge-check--pass {
    color: var(--success);
}
.challenge-check--fail {
    color: var(--error);
}

/* Hints */
.challenge-hints {
    margin-top: 0.75rem;
}
.challenge-hint-toggle {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 0.8rem;
    cursor: pointer;
    padding: 0;
    text-decoration: underline;
    text-underline-offset: 2px;
}
.challenge-hint-toggle:hover {
    color: var(--text-secondary);
}
.challenge-hint-list {
    margin-top: 0.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}
.challenge-hint-item {
    font-size: 0.78rem;
    color: var(--text-muted);
    padding: 0.3rem 0.5rem;
    background: var(--bg-secondary, #12122a);
    border-radius: 4px;
    border-left: 2px solid var(--accent);
}

/* Success celebration */
.challenge-success {
    text-align: center;
    padding: 1rem;
    background: linear-gradient(135deg, rgba(34,197,94,0.1), rgba(16,185,129,0.05));
    border: 1px solid rgba(34,197,94,0.3);
    border-radius: 8px;
    animation: challengePulse 0.5s ease;
}
.challenge-success-icon {
    font-size: 2rem;
    color: var(--warning);
    margin-bottom: 0.5rem;
}
.challenge-success strong {
    display: block;
    font-size: 1.1rem;
    color: var(--success);
    margin-bottom: 0.25rem;
}
.challenge-success p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin: 0;
}

@keyframes challengePulse {
    0% { transform: scale(0.95); opacity: 0; }
    50% { transform: scale(1.02); }
    100% { transform: scale(1); opacity: 1; }
}

@media (max-width: 600px) {
    .challenge-grid {
        grid-template-columns: 1fr;
    }
}

/* ── API Explorer Panel ── */

.vps-api-panel {
    position: fixed;
    top: 0;
    right: 0;
    width: 440px;
    height: 100vh;
    background: var(--bg-secondary);
    border-left: 1px solid var(--bg-tertiary);
    z-index: 200;
    display: flex;
    flex-direction: column;
    box-shadow: -4px 0 20px rgba(0,0,0,0.3);
}
.vps-api-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0.75rem;
    border-bottom: 1px solid var(--bg-tertiary);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-primary);
    flex-shrink: 0;
}
.vps-api-body {
    flex: 1;
    overflow-y: auto;
    padding: 0.75rem;
}

.vps-api-route-card {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.4rem 0.5rem;
    border: 1px solid var(--bg-tertiary);
    border-radius: 6px;
    margin-bottom: 0.35rem;
    cursor: pointer;
    transition: border-color 0.15s;
    font-size: 0.78rem;
}
.vps-api-route-card:hover {
    border-color: var(--text-muted);
}
.vps-api-route-card.active {
    border-color: #3b82f6;
    background: rgba(59,130,246,0.05);
}

.vps-api-method-badge {
    font-size: 0.65rem;
    font-weight: 700;
    padding: 0.1rem 0.35rem;
    border-radius: 3px;
    text-transform: uppercase;
    font-family: monospace;
    flex-shrink: 0;
    min-width: 38px;
    text-align: center;
}
.vps-api-method-badge--get { background: rgba(34,197,94,0.15); color: var(--success); }
.vps-api-method-badge--post { background: rgba(59,130,246,0.15); color: #3b82f6; }
.vps-api-method-badge--put { background: color-mix(in srgb, var(--warning) 15%, transparent); color: var(--warning); }
.vps-api-method-badge--patch { background: color-mix(in srgb, var(--warning) 15%, transparent); color: var(--warning); }
.vps-api-method-badge--delete { background: rgba(239,68,68,0.15); color: var(--error); }
.vps-api-method-badge--any { background: rgba(136,136,136,0.15); color: #888; }

.vps-api-route-pattern {
    font-family: monospace;
    color: var(--text-secondary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}
.vps-api-route-file {
    margin-left: auto;
    font-size: 0.65rem;
    color: var(--text-muted);
    flex-shrink: 0;
}

.vps-api-req-row {
    display: flex;
    gap: 0.35rem;
    align-items: center;
}
.vps-api-method-select {
    width: 80px;
    font-size: 0.75rem;
    font-weight: 600;
    flex-shrink: 0;
}

.vps-api-body-editor {
    width: 100%;
    font-family: monospace;
    font-size: 0.75rem;
    background: var(--bg-secondary, #12122a);
    color: var(--text-primary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 4px;
    padding: 0.5rem;
    resize: vertical;
}

.vps-api-res-status {
    font-size: 0.8rem;
    font-weight: 600;
    margin-bottom: 0.4rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.vps-api-res-status .status-code {
    padding: 0.1rem 0.4rem;
    border-radius: 3px;
    font-family: monospace;
}
.vps-api-res-status .status-2xx { background: rgba(34,197,94,0.15); color: var(--success); }
.vps-api-res-status .status-4xx { background: color-mix(in srgb, var(--warning) 15%, transparent); color: var(--warning); }
.vps-api-res-status .status-5xx { background: rgba(239,68,68,0.15); color: var(--error); }
.vps-api-res-status .status-other { background: rgba(136,136,136,0.15); color: #888; }

.vps-api-res-body {
    background: var(--bg-secondary, #12122a);
    border: 1px solid var(--bg-tertiary);
    border-radius: 4px;
    padding: 0.5rem;
    font-size: 0.72rem;
    font-family: monospace;
    white-space: pre-wrap;
    word-break: break-word;
    max-height: 300px;
    overflow-y: auto;
    color: var(--text-secondary);
    margin: 0;
}

.vps-api-empty {
    padding: 1.5rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.8rem;
}

.vps-api-param-row {
    display: flex;
    align-items: center;
    gap: 0.35rem;
    margin-bottom: 0.3rem;
    font-size: 0.75rem;
}
.vps-api-param-row label {
    font-family: monospace;
    color: var(--warning);
    min-width: 60px;
}
.vps-api-param-row input {
    flex: 1;
}

@media (max-width: 768px) {
    .vps-api-panel {
        width: 100%;
    }
}

/* ── Firewall & Ports ── */

.vps-fw-ports {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}
.vps-fw-port {
    background: var(--bg-secondary);
    border: 1px solid var(--bg-tertiary);
    border-radius: 6px;
    padding: 0.4rem 0.6rem;
    text-align: center;
    min-width: 70px;
}
.vps-fw-port--open {
    border-color: rgba(34,197,94,0.3);
}
.vps-fw-port--blocked {
    border-color: rgba(239,68,68,0.3);
}
.vps-fw-port--inactive {
    opacity: 0.5;
}
.vps-fw-port-num {
    display: block;
    font-family: monospace;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-primary);
}
.vps-fw-port-label {
    display: block;
    font-size: 0.65rem;
    color: var(--text-muted);
}
.vps-fw-port-status {
    display: block;
    font-size: 0.6rem;
    margin-top: 0.15rem;
}
.vps-fw-port--open .vps-fw-port-status { color: var(--success); }
.vps-fw-port--blocked .vps-fw-port-status { color: var(--error); }
.vps-fw-port--inactive .vps-fw-port-status { color: var(--text-muted); }

.vps-fw-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.78rem;
}
.vps-fw-table th {
    text-align: left;
    padding: 0.3rem 0.5rem;
    color: var(--text-muted);
    border-bottom: 1px solid var(--bg-tertiary);
    font-weight: 500;
    font-size: 0.7rem;
}
.vps-fw-table td {
    padding: 0.3rem 0.5rem;
    border-bottom: 1px solid var(--bg-tertiary);
}
.vps-fw-action {
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    padding: 0.1rem 0.35rem;
    border-radius: 3px;
}
.vps-fw-action--allow {
    background: rgba(34,197,94,0.15);
    color: var(--success);
}
.vps-fw-action--deny {
    background: rgba(239,68,68,0.15);
    color: var(--error);
}

/* Simulated billing widget on the SDL dashboard. */
.vps-cost-widget {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem 1.1rem;
    margin: 0.5rem 0 1.5rem;
}
.vps-cost-head {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}
.vps-cost-label {
    font-size: 0.78rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}
.vps-cost-tag {
    display: inline-block;
    margin-left: 0.5rem;
    padding: 1px 8px;
    border-radius: 999px;
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    background: color-mix(in srgb, var(--warning) 15%, transparent);
    color: var(--warning);
    cursor: help;
}
.vps-cost-total {
    font-size: 1.7rem;
    font-weight: 700;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
}
.vps-cost-breakdown {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem 1.5rem;
    margin-top: 0.6rem;
    font-size: 0.85rem;
    color: var(--text-muted);
}
.vps-cost-breakdown b {
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
    margin-left: 0.25rem;
}
.vps-cost-foot {
    margin-top: 0.7rem;
    font-size: 0.75rem;
    color: var(--text-muted);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}
.vps-cost-toggle {
    background: none;
    border: none;
    color: var(--accent);
    cursor: pointer;
    font-size: 0.78rem;
    padding: 0;
}
.vps-cost-toggle:hover { text-decoration: underline; }
.vps-cost-detail {
    margin-top: 0.7rem;
    border-top: 1px solid var(--border);
    padding-top: 0.6rem;
}
.vps-cost-detail table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.82rem;
}
.vps-cost-detail th, .vps-cost-detail td {
    padding: 0.3rem 0.55rem;
    text-align: left;
    border-bottom: 1px solid var(--border);
}
.vps-cost-detail th {
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    color: var(--text-muted);
    font-weight: 600;
}
.vps-cost-detail td.amt {
    text-align: right;
    font-variant-numeric: tabular-nums;
}
.vps-cost-cat {
    display: inline-block;
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    padding: 1px 7px;
    border-radius: 999px;
    background: var(--bg-tertiary);
    color: var(--text-muted);
}

/* Inline price hint inside create-resource modals. Pairs with the
   simulated billing widget on the dashboard. */
.vps-price-hint {
    display: block;
    margin-top: 0.4rem;
    font-size: 0.78rem;
    color: var(--text-muted);
    line-height: 1.35;
}
.vps-price-hint b {
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
}
.vps-price-hint .vps-cost-tag {
    margin-left: 0.4rem;
}

/* Per-resource cost badge shown on detail-page headers. */
.vps-cost-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.78rem;
    color: var(--text-muted);
    padding: 2px 10px;
    border-radius: 6px;
    background: var(--bg-tertiary);
    font-variant-numeric: tabular-nums;
}

/* Diagnostics panel: shared between site, LB, and managed-DB detail pages.
   Rendered by assets/js/vps/diagnostics.js. */
.vps-diagnostics-panel {
    margin-top: 1rem;
    padding: 1rem 1.1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
}
.vps-diag-loading, .vps-diag-error {
    font-size: 0.85rem;
    color: var(--text-muted);
    padding: 0.5rem 0;
}
.vps-diag-error { color: var(--error); }
.vps-diag-summary {
    font-size: 0.85rem;
    font-weight: 600;
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    margin-bottom: 0.75rem;
}
.vps-diag-summary--ok   { background: color-mix(in srgb, var(--success) 15%, transparent);  color: var(--success); }
.vps-diag-summary--warn { background: color-mix(in srgb, var(--warning) 15%, transparent);  color: var(--warning); }
.vps-diag-summary--fail { background: rgba(239,68,68,0.15);   color: var(--error); }
.vps-diag-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}
.vps-diag-row {
    display: flex;
    gap: 0.7rem;
    align-items: flex-start;
    padding: 0.5rem 0.7rem;
    background: var(--bg-tertiary);
    border-radius: 5px;
    font-size: 0.85rem;
}
.vps-diag-row--fail { border-left: 3px solid var(--error); }
.vps-diag-row--warn { border-left: 3px solid var(--warning); }
.vps-diag-row--ok   { border-left: 3px solid var(--success); }
.vps-diag-status {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    font-weight: 700;
    font-size: 0.85rem;
    flex-shrink: 0;
    margin-top: 1px;
}
.vps-diag-status--ok   { background: color-mix(in srgb, var(--success) 20%, transparent);  color: var(--success); }
.vps-diag-status--warn { background: color-mix(in srgb, var(--warning) 20%, transparent);  color: var(--warning); }
.vps-diag-status--fail { background: rgba(239,68,68,0.2);   color: var(--error); }
.vps-diag-body { flex: 1; min-width: 0; }
.vps-diag-label { font-weight: 600; color: var(--text-primary); }
.vps-diag-msg, .vps-diag-hint {
    font-size: 0.78rem;
    color: var(--text-muted);
    margin-top: 0.2rem;
    line-height: 1.4;
}
.vps-diag-hint { color: var(--accent); }

/* Aggregate diagnostics: collapsible per-resource cards used by the
   teacher SDL inspection view. Reuses .vps-diag-summary above. */
.vps-diag-resource {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    margin: 0.5rem 0;
    overflow: hidden;
}
.vps-diag-resource.vps-diag-row--fail { border-left: 3px solid var(--error); }
.vps-diag-resource.vps-diag-row--warn { border-left: 3px solid var(--warning); }
.vps-diag-resource.vps-diag-row--ok   { border-left: 3px solid var(--success); }
.vps-diag-resource > summary {
    list-style: none;
    cursor: pointer;
    padding: 0.65rem 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.65rem;
    flex-wrap: wrap;
    user-select: none;
}
.vps-diag-resource > summary::-webkit-details-marker { display: none; }
.vps-diag-resource > summary::before {
    content: '▶';
    font-size: 0.7rem;
    color: var(--text-muted);
    transition: transform 0.12s ease;
}
.vps-diag-resource[open] > summary::before { transform: rotate(90deg); }
.vps-diag-resource-type {
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.4px;
    color: var(--text-muted);
    background: var(--bg-tertiary);
    padding: 1px 7px;
    border-radius: 999px;
}
.vps-diag-resource-name {
    font-weight: 600;
    color: var(--text-primary);
    flex: 1;
    min-width: 0;
}
.vps-diag-resource-counts {
    display: inline-flex;
    gap: 0.3rem;
    flex-wrap: wrap;
}
.vps-diag-resource-body {
    padding: 0.5rem 0.9rem 0.8rem;
    border-top: 1px solid var(--border);
}

/* guide callout: the line that keeps a student from worrying */
.ss-guide-note {
    border-left: 3px solid var(--accent, #5b8dd4);
    background: rgba(91, 141, 212, 0.07);
    padding: 0.6rem 0.9rem;
    border-radius: 0 6px 6px 0;
    font-size: 0.92rem;
}