/* =====================================================================
   VIBRANT STREAM — Shared Stylesheet
   ===================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:ital,opsz,wght,SOFT@0,9..144,300..700,0..100;1,9..144,300..700,0..100&family=Instrument+Sans:ital,wght@0,400..700;1,400..700&family=JetBrains+Mono:wght@400;500&family=Noto+Serif+SC:wght@300;400;500;600&family=Noto+Sans+SC:wght@300;400;500&display=swap');

:root {
    --bg: #080d1a;
    --bg-elevated: #0d1424;
    --surface: #131b2e;
    --surface-hover: #18213a;
    --border: rgba(196, 165, 120, 0.14);
    --border-strong: rgba(196, 165, 120, 0.28);
    --text: #f0ebe0;
    --text-muted: #8c98ad;
    --text-subtle: #5a6478;
    --accent: #c4a578;
    --accent-bright: #e6c995;
    --cyan: #7fc7d9;
    --cyan-deep: #4a8fa1;

    --font-display: 'Fraunces', 'Noto Serif SC', Georgia, serif;
    --font-body: 'Instrument Sans', 'Noto Sans SC', -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', 'Noto Sans SC', monospace;

    --max-width: 1240px;
    --content-width: 760px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-body);
    font-size: 17px;
    line-height: 1.65;
    font-weight: 400;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    min-height: 100vh;
}

/* Atmospheric background */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% -10%, rgba(196, 165, 120, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 90% 100%, rgba(127, 199, 217, 0.06) 0%, transparent 50%);
    pointer-events: none;
    z-index: 0;
}

body::after {
    content: '';
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.4 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
    opacity: 0.35;
    mix-blend-mode: overlay;
    pointer-events: none;
    z-index: 1;
}

/* =====================================================================
   NAVIGATION
   ===================================================================== */

.nav {
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    background: rgba(8, 13, 26, 0.7);
    border-bottom: 1px solid var(--border);
}

.nav-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 1.4rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    row-gap: 0.6rem;
}

.nav-brand {
    font-family: var(--font-display);
    font-size: 1.05rem;
    font-weight: 400;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--text);
    text-decoration: none;
    font-variation-settings: "SOFT" 50;
    transition: color 0.3s ease;
}

.nav-brand:hover {
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: 2.5rem;
    align-items: center;
}

.nav-links a {
    font-size: 0.78rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.3s ease;
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--accent);
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--accent);
}

/* =====================================================================
   LAYOUT
   ===================================================================== */

main {
    position: relative;
    z-index: 2;
}

.section {
    padding: 7rem 2rem;
    position: relative;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
}

.narrow {
    max-width: var(--content-width);
}

.section-divider {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 2rem;
}

.section-divider svg {
    width: 100%;
    height: 1px;
    opacity: 0.3;
}

/* =====================================================================
   HERO
   ===================================================================== */

.hero {
    min-height: 90vh;
    padding: 6rem 2rem 8rem;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
}

.hero-content {
    max-width: var(--max-width);
    margin: 0 auto;
    width: 100%;
    position: relative;
    z-index: 2;
}

.eyebrow {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.32em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 2rem;
    opacity: 0;
    animation: fadeUp 1s ease 0.2s forwards;
}

.hero h1 {
    font-family: var(--font-display);
    font-weight: 300;
    font-size: clamp(2.8rem, 7vw, 6rem);
    line-height: 0.98;
    letter-spacing: -0.02em;
    margin-bottom: 2rem;
    font-variation-settings: "SOFT" 30, "opsz" 144;
    max-width: 18ch;
    opacity: 0;
    animation: fadeUp 1.2s ease 0.4s forwards;
}

.hero h1 em {
    font-style: italic;
    color: var(--accent);
    font-weight: 300;
    font-variation-settings: "SOFT" 100, "opsz" 144;
}

.hero-lede {
    font-size: clamp(1.05rem, 1.6vw, 1.25rem);
    line-height: 1.65;
    color: var(--text-muted);
    max-width: 56ch;
    opacity: 0;
    animation: fadeUp 1.2s ease 0.7s forwards;
}

.hero-pulse {
    position: absolute;
    right: -10%;
    top: 50%;
    transform: translateY(-50%);
    width: 70%;
    max-width: 800px;
    opacity: 0.35;
    pointer-events: none;
    z-index: 1;
}

@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes pulse {
    0%, 100% { opacity: 0.25; }
    50% { opacity: 0.5; }
}

/* =====================================================================
   TYPOGRAPHY
   ===================================================================== */

h2 {
    font-family: var(--font-display);
    font-weight: 350;
    font-size: clamp(2rem, 4.5vw, 3.4rem);
    line-height: 1.05;
    letter-spacing: -0.015em;
    margin-bottom: 2rem;
    font-variation-settings: "SOFT" 40;
    max-width: 22ch;
}

h2 em {
    font-style: italic;
    color: var(--accent);
    font-variation-settings: "SOFT" 100;
}

h3 {
    font-family: var(--font-display);
    font-weight: 400;
    font-size: 1.6rem;
    line-height: 1.2;
    letter-spacing: -0.005em;
    margin-bottom: 1rem;
    color: var(--text);
}

h4 {
    font-family: var(--font-display);
    font-weight: 400;
    font-size: 1.2rem;
    line-height: 1.3;
    margin-bottom: 0.6rem;
    color: var(--text);
}

p {
    margin-bottom: 1.5rem;
    color: var(--text-muted);
    max-width: 65ch;
}

p strong {
    color: var(--text);
    font-weight: 500;
}

p em {
    color: var(--accent);
    font-style: italic;
    font-family: var(--font-display);
    font-size: 1.05em;
}

a {
    color: var(--accent);
    text-decoration: none;
    border-bottom: 1px solid var(--border-strong);
    transition: color 0.2s, border-color 0.2s;
    padding-bottom: 1px;
}

a:hover {
    color: var(--accent-bright);
    border-bottom-color: var(--accent);
}

.section-label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.32em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
}

.section-label::before {
    content: '';
    width: 24px;
    height: 1px;
    background: var(--accent);
}

/* =====================================================================
   ABOUT GRID
   ===================================================================== */

.split-grid {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 5rem;
    align-items: start;
}

@media (max-width: 860px) {
    .split-grid {
        grid-template-columns: 1fr;
        gap: 2.5rem;
    }
}

/* =====================================================================
   TIER CARDS
   ===================================================================== */

.tiers {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
    margin-top: 3rem;
}

@media (max-width: 860px) {
    .tiers {
        grid-template-columns: 1fr;
    }
}

.tier {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 2.5rem 2rem;
    border-radius: 2px;
    position: relative;
    transition: border-color 0.4s ease, transform 0.4s ease;
}

.tier:hover {
    border-color: var(--border-strong);
    transform: translateY(-2px);
}

.tier-num {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.3em;
    color: var(--accent);
    margin-bottom: 1.5rem;
    display: block;
}

.tier h3 {
    font-style: italic;
    margin-bottom: 1rem;
    font-variation-settings: "SOFT" 100;
    color: var(--accent-bright);
}

.tier p {
    font-size: 0.95rem;
    margin: 0;
}

/* =====================================================================
   LINEAGE
   ===================================================================== */

.lineage-list {
    list-style: none;
    margin-top: 2rem;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.8rem 2rem;
    max-width: 600px;
}

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

.lineage-list li {
    font-family: var(--font-display);
    font-style: italic;
    font-size: 1.1rem;
    color: var(--text);
    padding: 0.4rem 0;
    border-bottom: 1px solid var(--border);
    font-variation-settings: "SOFT" 100;
}

/* =====================================================================
   PULL QUOTE / CALLOUT
   ===================================================================== */

.pull-quote {
    font-family: var(--font-display);
    font-size: clamp(1.4rem, 2.6vw, 2.1rem);
    font-style: italic;
    line-height: 1.35;
    color: var(--text);
    font-weight: 300;
    font-variation-settings: "SOFT" 100, "opsz" 144;
    padding: 4rem 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    text-align: center;
    max-width: 24ch;
    margin: 0 auto;
}

.pull-quote em {
    color: var(--accent);
}

/* =====================================================================
   CTA
   ===================================================================== */

.cta-link {
    display: inline-flex;
    align-items: center;
    gap: 0.8rem;
    margin-top: 2.5rem;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--accent);
    border: none;
    padding: 0;
    transition: gap 0.3s ease;
}

.cta-link:hover {
    gap: 1.2rem;
    color: var(--accent-bright);
    border: none;
}

.cta-link svg {
    width: 28px;
    height: 12px;
}

/* =====================================================================
   RESEARCH PAGE: KEY FINDINGS
   ===================================================================== */

.findings-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    margin-top: 3rem;
}

@media (max-width: 720px) {
    .findings-grid {
        grid-template-columns: 1fr;
    }
}

.finding {
    padding: 3.5rem 2.5rem;
    text-align: left;
}

.finding:first-child {
    border-right: 1px solid var(--border);
}

@media (max-width: 720px) {
    .finding:first-child {
        border-right: none;
        border-bottom: 1px solid var(--border);
    }
}

.finding-stat {
    font-family: var(--font-display);
    font-size: clamp(3.5rem, 8vw, 5.5rem);
    line-height: 0.9;
    color: var(--accent-bright);
    font-weight: 300;
    letter-spacing: -0.03em;
    font-variation-settings: "SOFT" 30, "opsz" 144;
    margin-bottom: 1.5rem;
    display: block;
}

.finding-stat .pct {
    font-style: italic;
    font-variation-settings: "SOFT" 100;
    color: var(--accent);
    font-size: 0.7em;
    margin-left: 0.05em;
}

.finding-label {
    font-size: 1rem;
    color: var(--text-muted);
    line-height: 1.5;
    max-width: 32ch;
}

/* =====================================================================
   STUDY SECTION
   ===================================================================== */

.study {
    margin-bottom: 6rem;
}

.study:last-child {
    margin-bottom: 0;
}

.study-header {
    margin-bottom: 3rem;
}

.study-meta {
    display: flex;
    gap: 2.5rem;
    flex-wrap: wrap;
    margin: 1.5rem 0 2.5rem;
    padding: 1.5rem 0;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.study-meta-item {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
}

.study-meta-label {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--text-subtle);
}

.study-meta-value {
    font-family: var(--font-display);
    font-style: italic;
    font-size: 1rem;
    color: var(--text);
    font-variation-settings: "SOFT" 100;
}

/* =====================================================================
   DATA VISUALIZATION
   ===================================================================== */

.data-viz {
    background: var(--surface);
    border: 1px solid var(--border);
    padding: 3rem 2.5rem;
    margin: 3rem 0;
    border-radius: 2px;
}

.data-viz-title {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.data-viz-subtitle {
    font-family: var(--font-display);
    font-size: 1.2rem;
    color: var(--text);
    font-style: italic;
    font-variation-settings: "SOFT" 100;
    margin-bottom: 2.5rem;
}

.bar-row {
    display: grid;
    grid-template-columns: 200px 1fr 100px;
    align-items: center;
    gap: 1.5rem;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border);
}

.bar-row:last-child {
    border-bottom: none;
}

@media (max-width: 720px) {
    .bar-row {
        grid-template-columns: 1fr;
        gap: 0.5rem;
    }
}

.bar-label {
    font-size: 0.92rem;
    color: var(--text-muted);
    line-height: 1.3;
}

.bar-label strong {
    color: var(--text);
    display: block;
    font-weight: 500;
    margin-bottom: 0.15rem;
}

.bar-track {
    height: 6px;
    background: rgba(255, 255, 255, 0.04);
    border-radius: 1px;
    position: relative;
    overflow: hidden;
}

.bar-fill {
    position: absolute;
    inset: 0 auto 0 0;
    background: linear-gradient(90deg, var(--accent) 0%, var(--accent-bright) 100%);
    border-radius: 1px;
    transition: width 1.2s cubic-bezier(0.65, 0, 0.35, 1);
}

.bar-fill.cyan {
    background: linear-gradient(90deg, var(--cyan-deep) 0%, var(--cyan) 100%);
}

.bar-fill.muted {
    background: linear-gradient(90deg, rgba(140, 152, 173, 0.4) 0%, rgba(140, 152, 173, 0.7) 100%);
}

.bar-value {
    font-family: var(--font-mono);
    font-size: 0.92rem;
    color: var(--text);
    text-align: right;
    font-weight: 500;
}

@media (max-width: 720px) {
    .bar-value {
        text-align: left;
    }
}

.viz-note {
    font-size: 0.85rem;
    color: var(--text-subtle);
    font-style: italic;
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
    font-family: var(--font-display);
    font-variation-settings: "SOFT" 100;
}

/* =====================================================================
   DISCLOSURES
   ===================================================================== */

.disclosure-block {
    background: var(--bg-elevated);
    border-left: 2px solid var(--accent);
    padding: 2rem 2.5rem;
    margin-top: 2rem;
}

.disclosure-block p {
    font-size: 0.95rem;
    color: var(--text-muted);
}

.disclosure-block p:last-child {
    margin-bottom: 0;
}

/* =====================================================================
   CITATIONS
   ===================================================================== */

.citation-group {
    margin-bottom: 3rem;
}

.citation-group-label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 1rem;
    padding-bottom: 0.8rem;
    border-bottom: 1px solid var(--border);
}

.citation {
    padding: 1.4rem 0;
    border-bottom: 1px solid var(--border);
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 1.5rem;
}

.citation:last-child {
    border-bottom: none;
}

.citation-num {
    font-family: var(--font-mono);
    font-size: 0.82rem;
    color: var(--accent);
    padding-top: 0.2rem;
}

.citation-body {
    font-size: 0.95rem;
    color: var(--text-muted);
    line-height: 1.6;
}

.citation-body strong {
    color: var(--text);
    font-weight: 500;
    display: block;
    margin-bottom: 0.3rem;
}

.citation-body em {
    color: var(--accent);
    font-style: italic;
    font-family: var(--font-display);
    font-variation-settings: "SOFT" 100;
    font-size: 1em;
}

.citation-tag {
    display: block;
    width: fit-content;
    font-family: var(--font-mono);
    font-size: 0.65rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    padding: 0.3rem 0.7rem;
    border: 1px solid var(--border-strong);
    border-radius: 2px;
    color: var(--text-subtle);
    margin-top: 1rem;
}

.citation-tag.frontier {
    color: var(--cyan);
    border-color: var(--cyan-deep);
}

.citation-tag.established {
    color: var(--accent);
    border-color: var(--border-strong);
}

/* =====================================================================
   FOUR CORE ELEMENTS
   ===================================================================== */

.formula {
    font-family: var(--font-mono);
    font-size: clamp(1.08rem, 1.92vw, 1.44rem);
    color: var(--accent);
    letter-spacing: 0.12em;
    text-align: center;
    padding: 2.2rem 2rem;
    margin: 3rem auto;
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
    max-width: 700px;
    line-height: 1.6;
}

.formula .op {
    color: var(--text-muted);
    margin: 0 0.5em;
}

.formula .equals {
    color: var(--text);
    margin: 0 0.6em;
    font-weight: 500;
}

.formula .result {
    color: var(--accent-bright);
    font-style: italic;
    font-family: var(--font-display);
    font-size: 1.15em;
    font-variation-settings: "SOFT" 100;
    margin-left: 0.2em;
}

.callout {
    background: var(--surface);
    border-left: 2px solid var(--accent);
    padding: 2rem 2.5rem;
    margin: 2.5rem 0 3rem;
    font-family: var(--font-display);
    font-size: 1.05rem;
    line-height: 1.65;
    font-variation-settings: "SOFT" 50;
    color: var(--text-muted);
    max-width: 70ch;
}

.callout p {
    margin-bottom: 1rem;
    color: var(--text-muted);
    font-family: inherit;
    max-width: none;
}

.callout p:last-child {
    margin-bottom: 0;
}

.callout em {
    font-style: italic;
    color: var(--accent);
    font-variation-settings: "SOFT" 100;
}

.callout strong {
    color: var(--text);
    font-weight: 500;
    font-style: italic;
    font-variation-settings: "SOFT" 100;
}

.elements-list {
    margin-top: 4rem;
}

.element {
    display: grid;
    grid-template-columns: 130px 1fr;
    gap: 2.5rem;
    padding: 3rem 0;
    border-bottom: 1px solid var(--border);
    align-items: start;
}

.element:first-child {
    border-top: 1px solid var(--border);
}

@media (max-width: 720px) {
    .element {
        grid-template-columns: 1fr;
        gap: 1rem;
        padding: 2.5rem 0;
    }
}

.element-num {
    font-family: var(--font-display);
    font-size: clamp(3.2rem, 5.5vw, 4.5rem);
    line-height: 0.9;
    color: var(--accent);
    font-style: italic;
    font-variation-settings: "SOFT" 100, "opsz" 144;
    font-weight: 300;
    letter-spacing: -0.02em;
}

.element-content {
    padding-top: 0.5rem;
}

.element-tag {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--text-subtle);
    margin-bottom: 0.8rem;
    display: block;
}

.element-content h3 {
    font-family: var(--font-display);
    font-style: italic;
    color: var(--accent-bright);
    font-variation-settings: "SOFT" 100, "opsz" 144;
    font-size: clamp(1.8rem, 2.88vw, 2.28rem);
    line-height: 1.15;
    margin-bottom: 1.2rem;
    font-weight: 350;
}

.element-content p {
    font-size: 1rem;
    line-height: 1.7;
    margin: 0;
    max-width: 62ch;
}

.element-content p + p {
    margin-top: 1rem;
}

/* NIH-style citation block */
.source-citation {
    font-family: var(--font-display);
    font-style: italic;
    color: var(--text);
    border-left: 1px solid var(--accent);
    padding: 0.5rem 0 0.5rem 1.5rem;
    margin: 2rem 0;
    font-variation-settings: "SOFT" 100;
    font-size: 1.05rem;
    line-height: 1.6;
    max-width: 60ch;
}

.source-citation cite {
    display: block;
    font-style: normal;
    font-family: var(--font-mono);
    font-size: 0.68rem;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: #838b9a;
    margin-top: 0.9rem;
}

/* Closing summary block under elements */
.elements-coda {
    margin-top: 4rem;
    padding-top: 3rem;
    border-top: 1px solid var(--border);
    max-width: 65ch;
}

.elements-coda p {
    font-family: var(--font-display);
    font-size: 1.15rem;
    line-height: 1.65;
    color: var(--text);
    font-variation-settings: "SOFT" 50;
}

.elements-coda em {
    font-style: italic;
    color: var(--accent);
    font-variation-settings: "SOFT" 100;
}

/* White paper download link */
.download-link {
    display: inline-flex;
    align-items: center;
    gap: 1rem;
    margin-top: 3rem;
    padding: 1.2rem 1.6rem 1.2rem 1.8rem;
    border: 1px solid var(--border-strong);
    border-radius: 2px;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--text);
    transition: border-color 0.3s ease, background 0.3s ease, color 0.3s ease;
    background: transparent;
}

.download-link:hover {
    border-color: var(--accent);
    background: var(--surface);
    color: var(--accent-bright);
}

.download-link svg {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    color: var(--accent);
}

.download-link .download-meta {
    color: var(--text-subtle);
    font-size: 0.7rem;
    margin-left: 0.5rem;
}

/* =====================================================================
   FOOTER
   ===================================================================== */

footer {
    border-top: 1px solid var(--border);
    padding: 4rem 2rem 3rem;
    margin-top: 6rem;
    position: relative;
    z-index: 2;
}

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 2rem;
    flex-wrap: wrap;
}

.footer-brand {
    font-family: var(--font-display);
    font-style: italic;
    font-size: 1.4rem;
    color: var(--accent);
    font-variation-settings: "SOFT" 100;
    margin-bottom: 0.6rem;
}

.footer-tagline {
    font-size: 0.9rem;
    color: #838b9a;
    max-width: 30ch;
}

.footer-meta {
    text-align: right;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.15em;
    color: #838b9a;
    line-height: 1.8;
}

@media (max-width: 600px) {
    .footer-meta {
        text-align: left;
    }
}

/* =====================================================================
   SCROLL REVEAL
   ===================================================================== */

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 1s ease, transform 1s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* =====================================================================
   SECTION SPECIFIC
   ===================================================================== */

.bg-elevated {
    background: var(--bg-elevated);
    position: relative;
}

.bg-elevated::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--border);
}

.bg-elevated::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--border);
}

/* Ornamental wave divider */
.wave-divider {
    width: 100%;
    height: 40px;
    display: block;
    margin: 4rem auto;
    opacity: 0.4;
}

/* =====================================================================
   MOBILE REFINEMENTS
   ===================================================================== */

@media (max-width: 600px) {
    .nav-inner {
        padding: 1rem 1.25rem;
    }
    .nav-brand {
        font-size: 0.92rem;
        letter-spacing: 0.14em;
    }
    .nav-links {
        gap: 1.4rem;
    }
    .nav-links a {
        font-size: 0.7rem;
        letter-spacing: 0.16em;
    }
    .nav-links a.active::after {
        bottom: -6px;
    }

    .section {
        padding: 4.5rem 1.25rem;
    }

    .hero {
        padding: 4rem 1.25rem 5rem;
        min-height: 80vh;
    }

    .data-viz {
        padding: 2rem 1.25rem;
    }

    .callout {
        padding: 1.5rem 1.5rem;
    }

    .disclosure-block {
        padding: 1.5rem 1.5rem;
    }

    .finding {
        padding: 2.5rem 1.5rem;
    }

    .formula {
        padding: 1.8rem 1rem;
        letter-spacing: 0.08em;
    }

    .pull-quote {
        padding: 2.5rem 0;
    }

    footer {
        padding: 3rem 1.25rem 2.5rem;
    }
}

@media (max-width: 400px) {
    .nav-links {
        gap: 1rem;
    }
    .nav-links a {
        font-size: 0.62rem;
        letter-spacing: 0.12em;
    }
    .nav-brand {
        font-size: 0.85rem;
        letter-spacing: 0.12em;
    }

    .formula {
        font-size: 1.02rem;
        letter-spacing: 0.05em;
    }
    .formula .op {
        margin: 0 0.3em;
    }
    .formula .equals {
        margin: 0 0.4em;
    }
}

/* =====================================================================
   CHINESE / SIMPLIFIED CHINESE — body.zh class adjustments
   ===================================================================== */

/* Chinese characters do not benefit from text-transform: uppercase, and
   the wide letter-spacing used for English caps degrades CJK readability.
   These overrides restore natural Chinese typography while preserving the
   editorial feel. */

body.zh {
    font-feature-settings: "palt";
    line-height: 1.75;
}

body.zh .nav-brand {
    text-transform: none;
    letter-spacing: 0.08em;
}

body.zh .nav-links a {
    text-transform: none;
    letter-spacing: 0.08em;
    font-size: 0.85rem;
}

body.zh .eyebrow,
body.zh .section-label,
body.zh .data-viz-title,
body.zh .study-meta-label,
body.zh .citation-group-label,
body.zh .element-tag,
body.zh .footer-meta {
    text-transform: none;
    letter-spacing: 0.08em;
    font-size: 0.78rem;
}

body.zh .citation-tag {
    text-transform: none;
    letter-spacing: 0.06em;
}

body.zh .source-citation cite {
    text-transform: none;
    letter-spacing: 0.06em;
}

body.zh .citation-num {
    letter-spacing: 0;
}

/* The formula is mostly Latin operators; only mild adjustment needed */
body.zh .formula {
    letter-spacing: 0.06em;
    line-height: 1.7;
}

/* Display headings — slightly tighter line-height for Chinese display */
body.zh .hero h1,
body.zh h2,
body.zh h3,
body.zh h4 {
    line-height: 1.25;
}

body.zh .hero h1 {
    line-height: 1.15;
    max-width: 22ch;
}

/* Element titles get a little extra room since Chinese chars are denser */
body.zh .element-content h3 {
    line-height: 1.25;
}

/* Pull quote */
body.zh .pull-quote {
    line-height: 1.5;
    max-width: 28ch;
}

/* The numeric finding stats and bar values stay Latin-monospaced */
body.zh .finding-stat,
body.zh .bar-value {
    letter-spacing: 0;
}

/* Language toggle in nav — slight visual separation */
.nav-links a.lang-toggle {
    margin-left: 0.5rem;
    padding-left: 1.5rem;
    border-left: 1px solid var(--border);
}

@media (max-width: 600px) {
    .nav-links a.lang-toggle {
        margin-left: 0.2rem;
        padding-left: 1rem;
    }
}