:root {
    --bg-primary: #0a0e17;
    --bg-secondary: #111827;
    --bg-panel: #1a1f2e;
    --border: #2a3142;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --green: #10b981;
    --green-dim: #065f46;
    --red: #ef4444;
    --red-dim: #7f1d1d;
    --blue: #3b82f6;
    --yellow: #f59e0b;
    --cyan: #06b6d4;
    --purple: #8b5cf6;
    --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', 'Cascadia Code', monospace;
    --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: var(--font-mono);
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
}

/* ── Navigation ── */
.site-nav {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 8px 16px;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav-logo {
    font-weight: 700;
    font-size: 13px;
    color: var(--cyan);
    letter-spacing: 1px;
    margin-right: 16px;
    text-decoration: none;
}

.nav-link {
    font-size: 11px;
    color: var(--text-secondary);
    text-decoration: none;
    padding: 6px 12px;
    border-radius: 4px;
    transition: all 0.15s;
    letter-spacing: 0.5px;
}

.nav-link:hover {
    color: var(--text-primary);
    background: var(--bg-panel);
}

.nav-link.active {
    color: var(--cyan);
    background: rgba(6, 182, 212, 0.1);
    border: 1px solid rgba(6, 182, 212, 0.3);
}

.nav-spacer { flex: 1; }

.nav-badge {
    font-size: 10px;
    background: var(--bg-panel);
    border: 1px solid var(--border);
    padding: 3px 8px;
    border-radius: 3px;
    color: var(--text-muted);
}

/* ── Content Pages ── */
.page-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 32px 24px;
}

.page-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.page-subtitle {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 32px;
}

/* ── Explainer Sections ── */
.section {
    margin-bottom: 48px;
}

.section-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--cyan);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.section-title::before {
    content: '▸';
    color: var(--text-muted);
}

.section-body {
    font-family: var(--font-sans);
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-secondary);
}

.section-body p {
    margin-bottom: 12px;
}

.section-body strong {
    color: var(--text-primary);
}

/* ── Code Blocks ── */
.code-block {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 16px;
    margin: 16px 0;
    overflow-x: auto;
    font-family: var(--font-mono);
    font-size: 12px;
    line-height: 1.6;
    color: var(--text-primary);
}

.code-block .comment { color: var(--text-muted); }
.code-block .keyword { color: var(--purple); }
.code-block .type { color: var(--cyan); }
.code-block .string { color: var(--green); }
.code-block .number { color: var(--yellow); }

.code-label {
    font-size: 10px;
    color: var(--text-muted);
    letter-spacing: 1px;
    margin-bottom: 8px;
    display: block;
}

/* ── Flowcharts (ASCII) ── */
.flowchart {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 20px;
    margin: 16px 0;
    font-family: var(--font-mono);
    font-size: 12px;
    line-height: 1.5;
    color: var(--cyan);
    white-space: pre;
    overflow-x: auto;
}

/* ── Bullet Lists ── */
.feature-list {
    list-style: none;
    margin: 12px 0;
}

.feature-list li {
    padding: 6px 0 6px 20px;
    position: relative;
    font-family: var(--font-sans);
    font-size: 13px;
    color: var(--text-secondary);
}

.feature-list li::before {
    content: '●';
    position: absolute;
    left: 0;
    color: var(--cyan);
    font-size: 8px;
    top: 10px;
}

/* ── Metric Cards ── */
.metric-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 12px;
    margin: 16px 0;
}

.metric-card {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 16px;
    text-align: center;
}

.metric-card-label {
    font-size: 10px;
    color: var(--text-muted);
    letter-spacing: 1px;
    margin-bottom: 6px;
}

.metric-card-value {
    font-size: 22px;
    font-weight: 700;
    color: var(--cyan);
    font-variant-numeric: tabular-nums;
}

.metric-card-unit {
    font-size: 10px;
    color: var(--text-muted);
    margin-top: 2px;
}

/* ── Tables ── */
.data-table {
    width: 100%;
    border-collapse: collapse;
    margin: 16px 0;
    font-size: 12px;
}

.data-table th {
    text-align: left;
    padding: 8px 12px;
    border-bottom: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 10px;
    letter-spacing: 1px;
}

.data-table td {
    padding: 8px 12px;
    border-bottom: 1px solid rgba(42, 49, 66, 0.5);
    color: var(--text-secondary);
}

.data-table tr:hover td {
    background: var(--bg-secondary);
}

/* ── Scenario Cards ── */
.scenario-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px;
    margin: 16px 0;
}

.scenario-card {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 20px;
    cursor: pointer;
    transition: all 0.2s;
}

.scenario-card:hover {
    border-color: var(--cyan);
    transform: translateY(-2px);
}

.scenario-card.active {
    border-color: var(--green);
    box-shadow: 0 0 12px rgba(16, 185, 129, 0.15);
}

.scenario-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.scenario-desc {
    font-size: 12px;
    color: var(--text-muted);
    font-family: var(--font-sans);
    margin-bottom: 12px;
}

.scenario-meta {
    display: flex;
    gap: 12px;
    font-size: 10px;
    color: var(--text-secondary);
}

.scenario-meta span { white-space: nowrap; }

/* ── Buttons ── */
.btn {
    font-family: var(--font-mono);
    font-size: 11px;
    padding: 8px 16px;
    border: 1px solid var(--border);
    border-radius: 4px;
    background: var(--bg-panel);
    color: var(--text-primary);
    cursor: pointer;
    transition: all 0.15s;
    letter-spacing: 0.5px;
}

.btn:hover {
    border-color: var(--cyan);
    color: var(--cyan);
}

.btn-primary {
    background: var(--cyan);
    color: var(--bg-primary);
    border-color: var(--cyan);
    font-weight: 600;
}

.btn-primary:hover {
    background: #0891b2;
}

.btn-danger {
    border-color: var(--red);
    color: var(--red);
}

.btn-danger:hover {
    background: var(--red-dim);
}

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 4px; height: 4px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }