/* =========================================================
   tanso.bar — carbon as descent
   Palette:
     #0b0b0f Soot Black     — primary background
     #2d2d34 Charcoal Gray  — secondary surfaces, striations
     #8a8a97 Graphite Silver — body text, lattices
     #e8e5df Diamond White   — display, crystal lines
     #c4883a Amber Inclusion — accent (depth gauge, fullerene)
     #6b5b8a Prismatic Violet — crystal stroke accents
   ========================================================= */

:root {
    --soot: #0b0b0f;
    --charcoal: #2d2d34;
    --graphite: #8a8a97;
    --diamond: #e8e5df;
    --amber: #c4883a;
    --prismatic: #6b5b8a;

    --font-display: "Zen Kaku Gothic New", "Hiragino Kaku Gothic ProN", system-ui, sans-serif;
    --font-body: "Cormorant Garamond", "Lora", Georgia, serif;
    --font-mono: "IBM Plex Mono", "Space Mono", "Inter", monospace;

    --stratum-min-h: 100vh;
}

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

html {
    scroll-behavior: smooth;
    background: var(--soot);
    overflow-x: hidden;
}

body {
    background: var(--soot);
    color: var(--graphite);
    font-family: var(--font-body);
    font-size: 18px;
    line-height: 2.0;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
    position: relative;
    min-height: 100vh;
}

body.locked {
    overflow: hidden;
    height: 100vh;
}

/* =========================================================
   Overture — opening blackout & seed atom
   ========================================================= */
.overture {
    position: fixed;
    inset: 0;
    background: #000;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
    transition: opacity 1.2s ease 1.4s, visibility 0s linear 2.6s;
}

.overture.dissolving {
    opacity: 0;
    visibility: hidden;
}

.seed-atom {
    width: 3px;
    height: 3px;
    border-radius: 50%;
    background: var(--diamond);
    box-shadow: 0 0 0 0 rgba(232, 229, 223, 0);
    opacity: 0;
    animation: seed-bloom 2s ease-out 0.8s forwards;
}

@keyframes seed-bloom {
    0% {
        opacity: 0;
        transform: scale(0.3);
        filter: blur(0px);
        box-shadow: 0 0 0 0 rgba(232, 229, 223, 0);
    }
    20% {
        opacity: 1;
        transform: scale(1);
        filter: blur(0px);
    }
    60% {
        opacity: 0.85;
        transform: scale(60);
        filter: blur(8px);
        box-shadow: 0 0 240px 60px rgba(232, 229, 223, 0.18);
    }
    100% {
        opacity: 0;
        transform: scale(180);
        filter: blur(40px);
        box-shadow: 0 0 480px 120px rgba(232, 229, 223, 0);
    }
}

/* =========================================================
   Page-wide noise veil
   ========================================================= */
.noise-veil {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 2;
    opacity: 0.55;
    background-image: url("data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' width='220' height='220'><filter id='n'><feTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/><feColorMatrix type='matrix' values='0 0 0 0 0.18  0 0 0 0 0.18  0 0 0 0 0.21  0 0 0 0.55 0'/></filter><rect width='100%' height='100%' filter='url(%23n)'/></svg>");
    background-size: 220px 220px;
    mix-blend-mode: overlay;
    transition: opacity 1.2s ease;
}

body.depth-crystal .noise-veil { opacity: 0.32; }
body.depth-molecular .noise-veil { opacity: 0.18; }

/* =========================================================
   Carbon dust particle drift
   ========================================================= */
.particle-drift {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 3;
    overflow: hidden;
}

.particle {
    position: absolute;
    width: 3px;
    height: 3px;
    border-radius: 50%;
    background: var(--diamond);
    opacity: 0;
    animation: particle-rise linear infinite;
}

@keyframes particle-rise {
    0% {
        transform: translateY(110vh) translateX(0);
        opacity: 0;
    }
    8% { opacity: 0.10; }
    50% { opacity: 0.12; }
    92% { opacity: 0.05; }
    100% {
        transform: translateY(-15vh) translateX(20px);
        opacity: 0;
    }
}

.p1  { left: 4%;  width:2px; height:2px; animation-duration: 28s; animation-delay: -3s; }
.p2  { left: 11%; width:3px; height:3px; animation-duration: 36s; animation-delay: -8s; }
.p3  { left: 18%; width:2px; height:2px; animation-duration: 22s; animation-delay: -1s; }
.p4  { left: 24%; width:4px; height:4px; animation-duration: 40s; animation-delay: -14s; }
.p5  { left: 31%; width:2px; height:2px; animation-duration: 26s; animation-delay: -6s; }
.p6  { left: 38%; width:3px; height:3px; animation-duration: 33s; animation-delay: -18s; }
.p7  { left: 45%; width:2px; height:2px; animation-duration: 19s; animation-delay: -2s; }
.p8  { left: 52%; width:3px; height:3px; animation-duration: 30s; animation-delay: -10s; }
.p9  { left: 58%; width:4px; height:4px; animation-duration: 38s; animation-delay: -22s; }
.p10 { left: 65%; width:2px; height:2px; animation-duration: 24s; animation-delay: -5s; }
.p11 { left: 71%; width:3px; height:3px; animation-duration: 31s; animation-delay: -12s; }
.p12 { left: 78%; width:2px; height:2px; animation-duration: 27s; animation-delay: -7s; }
.p13 { left: 84%; width:4px; height:4px; animation-duration: 35s; animation-delay: -16s; }
.p14 { left: 89%; width:2px; height:2px; animation-duration: 21s; animation-delay: -4s; }
.p15 { left: 94%; width:3px; height:3px; animation-duration: 29s; animation-delay: -11s; }
.p16 { left: 7%;  width:2px; height:2px; animation-duration: 32s; animation-delay: -19s; }
.p17 { left: 27%; width:3px; height:3px; animation-duration: 25s; animation-delay: -9s; }
.p18 { left: 49%; width:2px; height:2px; animation-duration: 34s; animation-delay: -15s; }
.p19 { left: 67%; width:3px; height:3px; animation-duration: 23s; animation-delay: -3s; }
.p20 { left: 81%; width:2px; height:2px; animation-duration: 37s; animation-delay: -20s; }

/* =========================================================
   Depth Gauge (left edge)
   ========================================================= */
.depth-gauge {
    position: fixed;
    top: 8vh;
    left: clamp(20px, 4vw, 56px);
    width: 24px;
    height: 84vh;
    z-index: 50;
    pointer-events: none;
}

.gauge-line {
    position: absolute;
    left: 11px;
    top: 0;
    width: 2px;
    height: 100%;
    overflow: visible;
}

.gauge-stroke {
    stroke: var(--charcoal);
    stroke-width: 1;
    stroke-dasharray: 1000;
    stroke-dashoffset: 1000;
    animation: gauge-draw 1.5s ease-out 2.4s forwards;
}

@keyframes gauge-draw {
    to { stroke-dashoffset: 0; }
}

.gauge-dot {
    position: absolute;
    left: 6px;
    top: 0;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--graphite);
    box-shadow: 0 0 0 1px rgba(138, 138, 151, 0.3);
    transition: top 0.4s cubic-bezier(0.4, 0, 0.2, 1),
                background 0.8s ease,
                box-shadow 0.8s ease;
    opacity: 0;
    animation: gauge-dot-in 0.8s ease 3.6s forwards;
}

@keyframes gauge-dot-in {
    from { opacity: 0; transform: scale(0.4); }
    to   { opacity: 1; transform: scale(1); }
}

body.depth-surface     .gauge-dot { background: var(--graphite); box-shadow: 0 0 0 1px rgba(138, 138, 151, 0.3); }
body.depth-compression .gauge-dot { background: var(--graphite); box-shadow: 0 0 8px 2px rgba(232, 229, 223, 0.18); }
body.depth-crystal     .gauge-dot { background: var(--diamond);  box-shadow: 0 0 12px 3px rgba(232, 229, 223, 0.45); }
body.depth-molecular   .gauge-dot { background: var(--amber);    box-shadow: 0 0 14px 3px rgba(196, 136, 58, 0.55); }

.gauge-labels {
    position: absolute;
    left: 32px;
    top: 0;
    height: 100%;
    list-style: none;
    font-family: var(--font-mono);
    font-size: 10px;
    letter-spacing: 0.18em;
    color: var(--charcoal);
    opacity: 0;
    animation: gauge-dot-in 0.8s ease 3.8s forwards;
}

.gauge-labels li {
    position: absolute;
    transition: color 0.6s ease;
}
.gauge-labels li[data-stratum="surface"]     { top: 0%; }
.gauge-labels li[data-stratum="compression"] { top: 33%; }
.gauge-labels li[data-stratum="crystal"]     { top: 66%; }
.gauge-labels li[data-stratum="molecular"]   { top: 95%; }

body.depth-surface     .gauge-labels li[data-stratum="surface"],
body.depth-compression .gauge-labels li[data-stratum="compression"],
body.depth-crystal     .gauge-labels li[data-stratum="crystal"],
body.depth-molecular   .gauge-labels li[data-stratum="molecular"] {
    color: var(--diamond);
}

body.depth-molecular .gauge-labels li[data-stratum="molecular"] { color: var(--amber); }

/* =========================================================
   Stratum (sections)
   ========================================================= */
.stratum {
    position: relative;
    width: 100%;
    min-height: var(--stratum-min-h);
    padding: clamp(80px, 12vh, 160px) clamp(20px, 8vw, 140px);
    overflow: hidden;
    z-index: 5;
    transition: background 1.2s ease, filter 0.6s ease;
}

.stratum.transitioning { filter: blur(2px); }

/* =========================================================
   Striations (parallax horizontal lines)
   ========================================================= */
.striations {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
}

.striations .line {
    position: absolute;
    left: 0;
    right: 0;
    top: var(--y);
    height: 1px;
    background: var(--charcoal);
    opacity: 0.55;
    transform: translateY(0);
    will-change: transform;
}

.striations.dense .line { opacity: 0.45; }
.striations.sparse .line { opacity: 0.32; }
.striations.whisper .line { opacity: 0.22; }

.striations .line.bright { background: rgba(232, 229, 223, 0.22); }
.striations .line.amber  { background: rgba(196, 136, 58, 0.28); }

/* =========================================================
   Hex Lattice
   ========================================================= */
.hex-lattice {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 2;
}

.hex {
    fill: none;
    stroke: var(--graphite);
    stroke-width: 1;
    opacity: 0;
    stroke-dasharray: 200;
    stroke-dashoffset: 200;
    transform-origin: center;
}

.hex-lattice.scattered .hex {
    opacity: 0.18;
    stroke-dashoffset: 200;
}

.hex-lattice.scattered .hex.hex-broken {
    stroke-dasharray: 30 18 22 12 18 100;
    opacity: 0.12;
}

.hex-lattice.in-view .hex {
    animation: hex-draw 1.4s ease-out var(--delay, 0s) forwards;
}

@keyframes hex-draw {
    0%   { stroke-dashoffset: 200; opacity: 0; }
    40%  { opacity: 0.30; }
    100% { stroke-dashoffset: 0; opacity: 0.30; }
}

.hex-lattice.locked .hex.crystal-hex {
    stroke: var(--prismatic);
    stroke-width: 1.2;
}

.hex-lattice.locked.in-view .hex.crystal-hex {
    animation: hex-crystallize 1.6s ease-out var(--delay, 0s) forwards;
}

@keyframes hex-crystallize {
    0%   { stroke-dashoffset: 200; opacity: 0; }
    50%  { opacity: 0.55; }
    100% { stroke-dashoffset: 0; opacity: 0.55; }
}

/* =========================================================
   Surface stratum
   ========================================================= */
.stratum-surface {
    background: var(--soot);
    min-height: 110vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.surface-content {
    position: relative;
    z-index: 5;
    width: 100%;
    max-width: 1000px;
    text-align: center;
}

.domain-mark {
    font-family: var(--font-mono);
    font-size: 13px;
    letter-spacing: 0.28em;
    text-transform: lowercase;
    color: var(--graphite);
    margin-bottom: 24px;
    opacity: 0;
    animation: fade-up 1.2s ease 3.0s forwards;
}

.domain-mark .dot { color: var(--amber); }

.atomic-meta {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.32em;
    text-transform: uppercase;
    color: var(--charcoal);
    margin-bottom: clamp(40px, 6vh, 80px);
    opacity: 0;
    animation: fade-up 1.2s ease 3.2s forwards;
}

.kanji-stage {
    position: relative;
    margin: clamp(40px, 8vh, 100px) 0;
}

.kanji-svg {
    display: block;
    width: 100%;
    max-width: 800px;
    height: auto;
    margin: 0 auto;
    overflow: visible;
}

.kanji-glyph {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(6rem, 15vw, 16rem);
    fill: var(--diamond);
    fill-opacity: 0;
    letter-spacing: -0.02em;
    transition: fill-opacity 0.4s ease;
    animation: kanji-bloom 2.4s ease 3.6s forwards;
}

.kanji-glyph.kanji-tan { transform: translateX(-0.55em); }
.kanji-glyph.kanji-so  { transform: translateX(0.55em); }

@keyframes kanji-bloom {
    0%   { fill-opacity: 0; filter: blur(8px); }
    60%  { fill-opacity: 0.10; filter: blur(2px); }
    100% { fill-opacity: 0.08; filter: blur(0); }
}

.kanji-pronounce {
    display: block;
    font-family: var(--font-body);
    font-style: italic;
    font-size: 16px;
    letter-spacing: 0.06em;
    color: var(--graphite);
    margin-top: clamp(20px, 4vh, 40px);
    opacity: 0;
    animation: fade-up 1.2s ease 4.6s forwards;
}

.surface-whisper {
    font-family: var(--font-body);
    font-size: 14px;
    font-style: italic;
    letter-spacing: 0.04em;
    color: var(--charcoal);
    margin-top: clamp(60px, 10vh, 120px);
    opacity: 0;
    animation: fade-up 1.4s ease 5.2s forwards;
    line-height: 2.4;
}

@keyframes fade-up {
    from { opacity: 0; transform: translateY(12px); filter: blur(1px); }
    to   { opacity: 1; transform: translateY(0); filter: blur(0); }
}

/* =========================================================
   Compression stratum
   ========================================================= */
.stratum-compression {
    background: linear-color-mix(in srgb, var(--soot) 92%, var(--charcoal) 8%);
    background: var(--soot);
    min-height: 150vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.compression-content {
    position: relative;
    z-index: 5;
    width: 100%;
    max-width: 700px;
    margin: 0 auto;
    padding: 4rem 0;
}

.atomic-fragment {
    font-family: var(--font-body);
    font-size: clamp(18px, 1.6vw, 22px);
    line-height: 2.0;
    color: var(--graphite);
    font-style: italic;
    font-weight: 300;
    margin: clamp(80px, 14vh, 140px) 0;
    max-width: 520px;
    opacity: 0;
    transform: translateY(12px);
    filter: blur(1.5px);
    transition: opacity 0.9s ease, transform 0.9s ease, filter 0.9s ease;
}

.atomic-fragment[data-line="2"] { margin-left: clamp(60px, 18vw, 200px); max-width: 480px; }
.atomic-fragment[data-line="3"] { margin-left: clamp(20px, 6vw, 80px); max-width: 540px; }
.atomic-fragment[data-line="4"] { margin-left: clamp(80px, 22vw, 240px); max-width: 460px; }
.atomic-fragment[data-line="5"] { margin-left: clamp(0px, 2vw, 30px); max-width: 580px; }

.atomic-fragment.revealed {
    opacity: 1;
    transform: translateY(0);
    filter: blur(0);
}

.frag-marker {
    display: block;
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--charcoal);
    font-style: normal;
    font-weight: 400;
    margin-bottom: 14px;
    transition: color 0.6s ease;
}

.atomic-fragment.revealed .frag-marker {
    color: var(--graphite);
}

.frag-marker.amber-tone {
    color: var(--amber);
    opacity: 0.6;
}

.atomic-fragment em {
    color: var(--diamond);
    font-style: italic;
    opacity: 0.78;
}

/* Solo atom dots */
.solo-atom {
    position: absolute;
    top: var(--top);
    left: var(--left);
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--diamond);
    opacity: 0.22;
    box-shadow: 0 0 12px 1px rgba(232, 229, 223, 0.18);
    animation: atom-pulse var(--d, 8s) ease-in-out infinite alternate;
}

@keyframes atom-pulse {
    from { opacity: 0.10; transform: scale(0.8); }
    to   { opacity: 0.32; transform: scale(1.2); }
}

/* =========================================================
   Crystal stratum
   ========================================================= */
.stratum-crystal {
    background: var(--soot);
    min-height: 150vh;
    position: relative;
}

.prismatic-veil {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    opacity: 0.45;
    background:
        radial-gradient(circle at 20% 30%, rgba(107, 91, 138, 0.12) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(232, 229, 223, 0.06) 0%, transparent 45%),
        radial-gradient(circle at 50% 50%, rgba(107, 91, 138, 0.06) 0%, transparent 60%);
    mix-blend-mode: screen;
}

.crystal-content {
    position: relative;
    z-index: 5;
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr;
    gap: clamp(40px, 8vh, 100px);
    padding: 6vh 0;
}

.stratum-title {
    font-family: var(--font-mono);
    font-size: clamp(11px, 1.2vw, 14px);
    letter-spacing: 0.5em;
    text-transform: uppercase;
    font-weight: 400;
    color: var(--graphite);
    text-align: center;
    margin-bottom: 20px;
}

.title-bracket {
    color: var(--prismatic);
    margin: 0 0.5em;
    opacity: 0.7;
}

.amber-tone .title-bracket { color: var(--amber); }

.stratum-title.amber-tone { color: var(--amber); }

.diamond-stage {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    gap: clamp(40px, 8vw, 120px);
    min-height: 360px;
}

.diamond-wireframe {
    width: clamp(220px, 32vw, 360px);
    height: clamp(220px, 32vw, 360px);
    overflow: visible;
    animation: lattice-rotate 36s linear infinite;
    transform-origin: center;
}

@keyframes lattice-rotate {
    0%   { transform: rotate(0deg) rotateX(0deg); }
    100% { transform: rotate(360deg) rotateX(360deg); }
}

.dlat-face {
    fill: none;
    stroke: var(--diamond);
    stroke-width: 0.8;
    opacity: 0.5;
}

.dlat-edge {
    stroke: var(--prismatic);
    stroke-width: 0.6;
    opacity: 0.55;
}

.dlat-vertex {
    fill: var(--diamond);
    opacity: 0.9;
}

.dlat-vertex.core {
    fill: var(--prismatic);
}

.facet-draw {
    width: clamp(180px, 22vw, 260px);
    height: clamp(180px, 22vw, 260px);
}

.facet-path {
    fill: none;
    stroke: var(--prismatic);
    stroke-width: 1;
    stroke-dasharray: 600;
    stroke-dashoffset: 600;
    opacity: 0.75;
}

.stratum-crystal.in-view .facet-path {
    animation: facet-stroke 2.4s ease-out forwards;
}

.facet-path.facet-1 { animation-delay: 0.2s; }
.facet-path.facet-2 { animation-delay: 0.6s; }
.facet-path.facet-3 { animation-delay: 1.0s; }
.facet-path.facet-4 { animation-delay: 1.4s; }
.facet-path.facet-5 { animation-delay: 1.8s; }

@keyframes facet-stroke {
    to { stroke-dashoffset: 0; }
}

.crystal-prose {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: clamp(30px, 5vw, 60px);
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 clamp(20px, 4vw, 60px);
}

.crystal-line {
    font-family: var(--font-body);
    font-size: clamp(16px, 1.4vw, 19px);
    line-height: 1.9;
    color: var(--graphite);
    font-weight: 300;
    opacity: 0;
    transform: translateY(12px);
    filter: blur(1.5px);
    transition: opacity 0.9s ease, transform 0.9s ease, filter 0.9s ease;
}

.crystal-line.revealed {
    opacity: 1;
    transform: translateY(0);
    filter: blur(0);
}

.crystal-line .frag-marker {
    color: var(--prismatic);
    opacity: 0.65;
}

.crystal-line.revealed .frag-marker { opacity: 1; }

/* =========================================================
   Molecular stratum
   ========================================================= */
.stratum-molecular {
    background: var(--soot);
    min-height: 150vh;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.amber-undertone {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    opacity: 0.5;
    background:
        radial-gradient(circle at 50% 60%, rgba(196, 136, 58, 0.08) 0%, transparent 55%),
        radial-gradient(circle at 30% 40%, rgba(196, 136, 58, 0.05) 0%, transparent 50%),
        radial-gradient(circle at 70% 80%, rgba(196, 136, 58, 0.06) 0%, transparent 45%);
    mix-blend-mode: screen;
}

.molecular-content {
    position: relative;
    z-index: 5;
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
    padding: 4rem 0;
}

.molecular-intro {
    font-family: var(--font-body);
    font-size: clamp(18px, 1.6vw, 22px);
    line-height: 2.0;
    color: var(--graphite);
    font-style: italic;
    font-weight: 300;
    max-width: 560px;
    margin: clamp(40px, 8vh, 80px) auto;
    opacity: 0;
    transform: translateY(12px);
    filter: blur(1.5px);
    transition: opacity 0.9s ease, transform 0.9s ease, filter 0.9s ease;
    text-align: left;
}

.molecular-intro.revealed {
    opacity: 1;
    transform: translateY(0);
    filter: blur(0);
}

/* Buckyball field (background spheres) */
.buckyball-field {
    position: absolute;
    inset: 0;
    pointer-events: none;
    z-index: 1;
}

.buckyball {
    position: absolute;
    border-radius: 50%;
    background: radial-gradient(circle at 35% 30%,
        rgba(232, 229, 223, 0.28) 0%,
        rgba(196, 136, 58, 0.10) 35%,
        rgba(11, 11, 15, 0.0) 70%);
    box-shadow:
        inset -10px -14px 30px rgba(11, 11, 15, 0.6),
        inset 8px 10px 24px rgba(232, 229, 223, 0.10),
        0 0 60px rgba(196, 136, 58, 0.06);
    animation: bucky-drift 18s ease-in-out infinite alternate;
    opacity: 0.7;
}

.buckyball.b1 { width: 90px;  height: 90px;  top: 12%; left: 14%; animation-duration: 22s; }
.buckyball.b2 { width: 60px;  height: 60px;  top: 70%; left: 78%; animation-duration: 18s; animation-delay: -4s; }
.buckyball.b3 { width: 110px; height: 110px; top: 78%; left: 8%;  animation-duration: 26s; animation-delay: -10s; }
.buckyball.b4 { width: 50px;  height: 50px;  top: 18%; left: 82%; animation-duration: 20s; animation-delay: -7s; }

@keyframes bucky-drift {
    from { transform: translate(0, 0) scale(1); }
    to   { transform: translate(20px, -30px) scale(1.06); }
}

/* C60 central SVG */
.c60-stage {
    position: relative;
    margin: clamp(40px, 6vh, 80px) auto;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 4;
}

.c60-svg {
    width: clamp(280px, 38vw, 460px);
    height: clamp(280px, 38vw, 460px);
    overflow: visible;
}

.c60-rotor {
    transform-origin: center;
    transform-box: fill-box;
    animation: c60-spin 60s linear infinite;
}

@keyframes c60-spin {
    0%   { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.c60-edge {
    fill: none;
    stroke: var(--prismatic);
    stroke-width: 0.7;
    opacity: 0.7;
}

.c60-edge.faint { stroke-opacity: 0.35; stroke-width: 0.5; }

.c60-ring-outer { stroke: var(--prismatic); opacity: 0.85; stroke-width: 1; }
.c60-ring-mid   { stroke: var(--prismatic); opacity: 0.55; }
.c60-ring-inner { stroke: var(--prismatic); opacity: 0.40; }

.c60-vertex {
    fill: var(--diamond);
    opacity: 0.92;
}

.c60-vertex.core {
    fill: var(--amber);
}

.closing-line {
    font-family: var(--font-body);
    font-size: clamp(17px, 1.5vw, 21px);
    line-height: 2.0;
    color: var(--graphite);
    font-style: italic;
    font-weight: 300;
    max-width: 560px;
    margin: clamp(40px, 8vh, 80px) auto;
    opacity: 0;
    transform: translateY(12px);
    filter: blur(1.5px);
    transition: opacity 0.9s ease, transform 0.9s ease, filter 0.9s ease;
    text-align: center;
}

.closing-line.revealed {
    opacity: 1;
    transform: translateY(0);
    filter: blur(0);
}

.closing-line em {
    color: var(--diamond);
    font-style: italic;
    opacity: 0.86;
}

.closing-meta {
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.32em;
    text-transform: lowercase;
    color: var(--charcoal);
    margin-top: clamp(60px, 10vh, 120px);
    line-height: 2.4;
}

.closing-meta .meta-small {
    color: rgba(196, 136, 58, 0.55);
    letter-spacing: 0.4em;
}

/* =========================================================
   Responsive tweaks
   ========================================================= */
@media (max-width: 768px) {
    body { font-size: 16px; }

    .depth-gauge {
        left: 12px;
        width: 16px;
    }

    .gauge-labels { display: none; }

    .stratum {
        padding: clamp(60px, 10vh, 100px) clamp(28px, 6vw, 50px);
    }

    .crystal-content {
        gap: 50px;
    }

    .diamond-stage {
        flex-direction: column;
        gap: 50px;
    }

    .atomic-fragment[data-line="2"],
    .atomic-fragment[data-line="3"],
    .atomic-fragment[data-line="4"],
    .atomic-fragment[data-line="5"] {
        margin-left: 0;
    }

    .crystal-prose {
        grid-template-columns: 1fr;
    }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.001ms !important;
        animation-delay: 0ms !important;
        transition-duration: 0.001ms !important;
    }
    .overture { display: none; }
    body.locked { overflow: auto; height: auto; }
}