:root {
    --bg: #f7f8fb;
    --surface: #ffffff;
    --surface-alt: #f3f4f6;
    --text: #111827;
    --text-muted: #4b5563;
    --text-light: #6b7280;
    --border: #e5e7eb;
    --primary: #2563eb;
    --primary-light: #dbeafe;
    --primary-dark: #1d4ed8;
    --success: #16a34a;
    --success-light: #dcfce7;
    --warning: #ea580c;
    --warning-light: #ffedd5;
    --danger: #dc2626;
    --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.04), 0 1px 3px rgba(15, 23, 42, 0.06);
    --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.06), 0 2px 4px rgba(15, 23, 42, 0.04);
    --shadow-lg: 0 12px 32px rgba(15, 23, 42, 0.08), 0 4px 8px rgba(15, 23, 42, 0.04);
    --radius: 12px;
    --radius-sm: 8px;
    --radius-lg: 16px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

/* ========== TOP NAV ========== */
.topnav {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: var(--shadow-sm);
}

.nav-inner {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 18px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
    gap: 14px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 8px;
    text-decoration: none;
    color: var(--text);
    font-weight: 700;
    font-size: 14px;
    white-space: nowrap;
    flex-shrink: 0;
}

.brand i {
    color: var(--primary);
    font-size: 18px;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 2px;
    flex-wrap: nowrap;
}

.nav-links a {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 6px 9px;
    border-radius: var(--radius-sm);
    text-decoration: none;
    color: var(--text-muted);
    font-size: 12.5px;
    font-weight: 500;
    transition: all 0.15s;
    white-space: nowrap;
}

.nav-links a:hover {
    background: var(--surface-alt);
    color: var(--text);
}

.nav-links a.active {
    background: var(--primary-light);
    color: var(--primary-dark);
}

.nav-links a i {
    font-size: 12px;
}

/* Medium screen: hide nav labels, show icons only to keep one row */
@media (max-width: 1180px) and (min-width: 901px) {
    .nav-links a span {
        display: none;
    }
    .nav-links a {
        padding: 8px 10px;
    }
    .nav-links a i {
        font-size: 15px;
    }
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text);
    font-size: 22px;
    cursor: pointer;
    padding: 4px 10px;
}

/* ========== HERO ========== */
.hero {
    background: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
    color: white;
    padding: 80px 24px;
    text-align: center;
}

.hero.compact {
    padding: 56px 24px 48px;
}

.hero.home {
    padding: 96px 24px 88px;
}

.hero-inner {
    max-width: 880px;
    margin: 0 auto;
}

.hero-icon {
    font-size: 36px;
    margin-bottom: 16px;
    opacity: 0.95;
}

.hero h1 {
    font-size: clamp(28px, 4vw, 44px);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 14px;
    line-height: 1.15;
}

.hero-subtitle {
    font-size: clamp(15px, 2vw, 18px);
    opacity: 0.92;
    max-width: 760px;
    margin: 0 auto;
    line-height: 1.6;
}

/* ========== CONTENT LAYOUT ========== */
.content {
    max-width: 1280px;
    margin: 0 auto;
    padding: 48px 24px 64px;
}

.block {
    margin-bottom: 56px;
}

.block-title {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 20px;
    letter-spacing: -0.01em;
}

/* ========== STATS GRID ========== */
.stat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 18px;
    margin-bottom: 28px;
}

.stat-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow-sm);
    transition: transform 0.15s, box-shadow 0.15s;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.stat-icon {
    width: 44px;
    height: 44px;
    border-radius: 10px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    margin-bottom: 14px;
}

.stat-value {
    font-size: 32px;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text);
}

.stat-label {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-muted);
    margin-top: 4px;
}

.stat-desc {
    font-size: 12.5px;
    color: var(--text-light);
    margin-top: 6px;
    line-height: 1.5;
}

/* ========== CARDS GENERIC ========== */
.card-grid {
    display: grid;
    gap: 18px;
}

.card-grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
}

.card-grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

/* Link / Research cards */
.link-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    text-decoration: none;
    color: var(--text);
    transition: transform 0.15s, box-shadow 0.15s, border-color 0.15s;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.link-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary);
}

.link-icon {
    width: 44px;
    height: 44px;
    border-radius: 10px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.link-card h3 {
    font-size: 17px;
    font-weight: 600;
}

.link-card p {
    color: var(--text-muted);
    font-size: 14px;
    flex-grow: 1;
}

.link-arrow {
    color: var(--primary);
    font-size: 13px;
    font-weight: 600;
    margin-top: 6px;
}

/* Info & Feature cards */
.info-card,
.feature-card,
.conclusion-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    box-shadow: var(--shadow-sm);
    display: flex;
    gap: 16px;
}

.info-card {
    flex-direction: column;
}

.info-icon,
.feature-icon,
.conclusion-icon {
    width: 44px;
    height: 44px;
    flex-shrink: 0;
    border-radius: 10px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.info-card h3,
.feature-card h3,
.conclusion-card h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 6px;
}

.info-card p,
.feature-card p,
.conclusion-card p {
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1.55;
}

/* Text card */
.text-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 32px;
    box-shadow: var(--shadow-sm);
}

.text-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    margin-bottom: 14px;
}

.text-card h2 {
    font-size: 21px;
    font-weight: 700;
    margin-bottom: 12px;
}

.text-card p {
    color: var(--text-muted);
    font-size: 15px;
    line-height: 1.7;
}

/* Source cards */
.source-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: var(--shadow-sm);
    display: flex;
    gap: 16px;
    align-items: flex-start;
}

.source-icon {
    width: 48px;
    height: 48px;
    flex-shrink: 0;
    border-radius: 10px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
}

.source-body h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 6px;
}

.source-body p {
    color: var(--text-muted);
    font-size: 14px;
    margin-bottom: 10px;
    line-height: 1.55;
}

.badge {
    display: inline-block;
    background: var(--primary-light);
    color: var(--primary-dark);
    padding: 4px 10px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 600;
}

/* ========== PIPELINE ========== */
.pipeline {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    flex-wrap: wrap;
    padding: 30px 16px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
}

.pipeline-step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    min-width: 90px;
}

.pipeline-step i {
    width: 56px;
    height: 56px;
    border-radius: 14px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
}

.pipeline-step span {
    font-size: 13px;
    font-weight: 600;
    color: var(--text);
}

.pipeline-arrow {
    color: var(--text-light);
    font-size: 18px;
    padding: 0 4px;
}

/* ========== CHARTS & FIGURES ========== */
.chart-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 16px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
}

.figure-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(440px, 1fr));
    gap: 18px;
}

.figure-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 18px;
    box-shadow: var(--shadow-sm);
}

.figure-card.single {
    padding: 18px;
}

.figure-card h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text);
}

.figure-chart {
    background: white;
    border-radius: var(--radius-sm);
    overflow: hidden;
}

.figure-caption {
    margin-top: 12px;
    color: var(--text-muted);
    font-size: 13.5px;
    line-height: 1.6;
}

/* Image gallery */
.image-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
    gap: 18px;
}

.image-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: transform 0.15s, box-shadow 0.15s;
}

.image-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.image-card img {
    width: 100%;
    height: auto;
    display: block;
    background: white;
}

.image-card figcaption {
    padding: 14px 18px;
    color: var(--text-muted);
    font-size: 13.5px;
    line-height: 1.5;
    border-top: 1px solid var(--border);
}

.inline-figure {
    margin: 14px 0;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    overflow: hidden;
    background: var(--surface);
}

.inline-figure img {
    width: 100%;
    height: auto;
    display: block;
}

.inline-figure figcaption {
    padding: 10px 14px;
    color: var(--text-muted);
    font-size: 12.5px;
    border-top: 1px solid var(--border);
}

/* ========== TABLES ========== */
.table-wrap {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    overflow-x: auto;
}

table.data-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13.5px;
}

table.data-table th {
    background: var(--surface-alt);
    text-align: left;
    padding: 11px 16px;
    font-weight: 600;
    color: var(--text);
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}

table.data-table td {
    padding: 10px 16px;
    border-bottom: 1px solid var(--border);
    color: var(--text-muted);
}

table.data-table tr:last-child td {
    border-bottom: none;
}

table.data-table tr:hover td {
    background: var(--surface-alt);
}

/* ========== TIMELINE ========== */
.timeline {
    list-style: none;
    position: relative;
    padding-left: 36px;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 14px;
    top: 8px;
    bottom: 8px;
    width: 2px;
    background: var(--border);
}

.timeline li {
    position: relative;
    margin-bottom: 22px;
}

.timeline-marker {
    position: absolute;
    left: -36px;
    top: 0;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
    box-shadow: 0 0 0 4px var(--bg);
}

.timeline-content {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 14px 18px;
    box-shadow: var(--shadow-sm);
}

.timeline-content h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 4px;
}

.timeline-content p {
    color: var(--text-muted);
    font-size: 13.5px;
}

/* ========== INSIGHT ========== */
.insight {
    background: var(--surface);
    border: 1px solid var(--border);
    border-left: 4px solid var(--primary);
    border-radius: var(--radius);
    padding: 18px 22px;
    display: flex;
    gap: 16px;
    align-items: flex-start;
    box-shadow: var(--shadow-sm);
}

.insight-icon {
    color: var(--primary);
    font-size: 22px;
    margin-top: 2px;
}

.insight h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 4px;
}

.insight p {
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1.6;
}

.insight-warning {
    border-left-color: var(--warning);
}

.insight-warning .insight-icon {
    color: var(--warning);
}

.insight-success {
    border-left-color: var(--success);
}

.insight-success .insight-icon {
    color: var(--success);
}

/* ========== HYPOTHESIS CARDS ========== */
.hypothesis-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 22px;
    margin-bottom: 18px;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--text-light);
}

.hypothesis-card.hypothesis-confirmed {
    border-left-color: var(--success);
}

.hypothesis-card.hypothesis-weak {
    border-left-color: var(--warning);
}

.hypothesis-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
    flex-wrap: wrap;
}

.hypothesis-tag {
    display: inline-block;
    background: var(--text);
    color: white;
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.04em;
}

.hypothesis-header h3 {
    font-size: 16px;
    font-weight: 600;
    flex-grow: 1;
}

.hypothesis-verdict {
    display: inline-block;
    background: var(--warning-light);
    color: var(--warning);
    padding: 5px 12px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 600;
}

.hypothesis-confirmed .hypothesis-verdict {
    background: var(--success-light);
    color: var(--success);
}

.hypothesis-reason {
    color: var(--text-muted);
    font-size: 13.5px;
    margin-bottom: 14px;
    line-height: 1.6;
}

.hypothesis-body table.data-table {
    margin-bottom: 12px;
}

.hypothesis-body .table-wrap,
.hypothesis-body table {
    margin-bottom: 12px;
}

/* ========== METRICS ========== */
.metric-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 16px;
}

.metric-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: var(--shadow-sm);
}

.metric-icon {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: var(--primary-light);
    color: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    margin-bottom: 12px;
}

.metric-value {
    font-size: 28px;
    font-weight: 700;
    letter-spacing: -0.02em;
}

.metric-label {
    font-size: 13.5px;
    font-weight: 600;
    color: var(--text-muted);
    margin-top: 4px;
}

.metric-desc {
    font-size: 12px;
    color: var(--text-light);
    margin-top: 4px;
}

/* ========== EXPLORER FORM ========== */
.explorer-form {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 22px;
    box-shadow: var(--shadow-sm);
    margin-bottom: 20px;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.form-row {
    display: flex;
    gap: 18px;
    flex-wrap: wrap;
    border: none;
}

.form-row label {
    display: flex;
    flex-direction: column;
    gap: 6px;
    flex: 1;
    min-width: 220px;
}

.form-row label > span,
.form-row legend {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
    padding: 0;
}

.form-row select {
    padding: 10px 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--surface);
    font-family: inherit;
    font-size: 14px;
    color: var(--text);
    cursor: pointer;
}

.form-row select:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
    border-color: var(--primary);
}

.checkbox-row {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-top: 8px;
}

.checkbox-pill {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 14px;
    border: 1px solid var(--border);
    border-radius: 999px;
    background: var(--surface);
    cursor: pointer;
    font-size: 13.5px;
    transition: all 0.15s;
}

.checkbox-pill input {
    accent-color: var(--primary);
}

.checkbox-pill:has(input:checked) {
    background: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary-dark);
}

.primary-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 20px;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    transition: background 0.15s, transform 0.1s;
    align-self: flex-start;
}

.primary-btn:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

/* ========== FINAL CTA ========== */
.final-cta {
    background: linear-gradient(135deg, #2563eb 0%, #7c3aed 100%);
    color: white;
    border-radius: var(--radius-lg);
    padding: 56px 32px;
    text-align: center;
}

.final-cta i {
    font-size: 36px;
    margin-bottom: 16px;
    opacity: 0.9;
}

.final-cta h2 {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 12px;
}

.final-cta p {
    font-size: 15px;
    line-height: 1.6;
    opacity: 0.92;
    max-width: 620px;
    margin: 0 auto 24px;
}

.final-cta .primary-btn {
    background: white;
    color: var(--primary);
    margin: 0 auto;
}

.final-cta .primary-btn:hover {
    background: rgba(255, 255, 255, 0.92);
}

/* ========== FOOTER ========== */
.footer {
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 28px 24px;
}

.footer-inner {
    max-width: 1280px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}

.footer p {
    color: var(--text-muted);
    font-size: 13.5px;
}

.footer a {
    color: var(--primary);
    text-decoration: none;
    font-size: 13.5px;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.footer a:hover {
    text-decoration: underline;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 900px) {
    .nav-toggle {
        display: inline-block;
    }
    .nav-links {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--surface);
        flex-direction: column;
        gap: 0;
        padding: 8px 16px;
        border-bottom: 1px solid var(--border);
        box-shadow: var(--shadow-md);
    }
    .nav-links.open {
        display: flex;
    }
    .nav-links a {
        padding: 12px;
        border-radius: var(--radius-sm);
    }
}

@media (max-width: 640px) {
    .content {
        padding: 32px 16px 48px;
    }
    .hero {
        padding: 56px 18px;
    }
    .hero.home {
        padding: 72px 18px 56px;
    }
    .block-title {
        font-size: 19px;
    }
    .stat-value {
        font-size: 26px;
    }
    .metric-value {
        font-size: 24px;
    }
}