/* ============================================================
   bada.quest — chrome cathedral beneath the sea
   Font names retained without network fetching: "Inter" (Google Fonts),
   "Space Mono" (Google Fonts); IntersectionObserver entry timing (threshold 0.2).
   ============================================================ */

:root {
    /* Palette — chrome / metallic / teal */
    --bg-deep: #0a0a0f;
    --bg-mid: #111119;
    --bg-panel: #1a1a24;
    --bg-panel-alt: #1c1c28;
    --bg-floor: #060608;

    --chrome-primary: #c8cdd5;
    --chrome-secondary: #8a919b;
    --chrome-tert: #6b727c;
    --silver-body: #a8aeb5;
    --silver-hi: #d4d8de;
    --highlight-flare: #e8ecf4;
    --biolum: #4a7c9b;
    --crystal-edge: #2a3040;
    --dim-chrome: #5a5f69;

    /* Type */
    --f-display: 'Cormorant Garamond', Georgia, serif;
    --f-body: 'Inter', system-ui, -apple-system, sans-serif;
    --f-mono: 'Space Mono', 'Courier New', monospace;

    --elastic: cubic-bezier(0.68, -0.55, 0.265, 1.55);
    --ease-deep: cubic-bezier(0.22, 1, 0.36, 1);

    --descent-ratio: 0;
}

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

html {
    scroll-behavior: smooth;
    background: var(--bg-deep);
}

body {
    min-height: 100vh;
    font-family: var(--f-body);
    font-weight: 400;
    font-size: clamp(0.95rem, 1.1vw, 1.15rem);
    line-height: 1.75;
    letter-spacing: -0.011em;
    color: var(--silver-body);
    background: var(--bg-deep);
    overflow-x: hidden;
    position: relative;
}

/* Subtle drifting atmosphere — the "deep water" layer */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    pointer-events: none;
    background:
        radial-gradient(ellipse 900px 700px at 20% 12%, rgba(74, 124, 155, 0.06) 0%, transparent 55%),
        radial-gradient(ellipse 700px 900px at 88% 68%, rgba(74, 124, 155, 0.04) 0%, transparent 60%),
        radial-gradient(ellipse 1200px 600px at 50% 100%, rgba(10, 10, 15, 0.8) 0%, transparent 60%);
    z-index: 0;
    transition: opacity 600ms var(--ease-deep);
}

main {
    position: relative;
    z-index: 1;
}

/* ============================================================
   GLOBAL READOUTS — Depth / Pressure instrument panel
   ============================================================ */

.depth-indicator,
.pressure-gauge {
    position: fixed;
    right: 2rem;
    font-family: var(--f-mono);
    font-size: 0.65rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--dim-chrome);
    z-index: 20;
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    padding: 0.9rem 1rem;
    border: 1px solid var(--crystal-edge);
    background: rgba(17, 17, 25, 0.55);
    backdrop-filter: blur(6px);
    -webkit-backdrop-filter: blur(6px);
    min-width: 160px;
}

.depth-indicator { top: 2rem; }
.pressure-gauge  { bottom: 2rem; }

.depth-indicator::before,
.pressure-gauge::before {
    content: '';
    position: absolute;
    top: -1px;
    left: -1px;
    width: 8px;
    height: 8px;
    border-top: 1px solid var(--biolum);
    border-left: 1px solid var(--biolum);
}
.depth-indicator::after,
.pressure-gauge::after {
    content: '';
    position: absolute;
    bottom: -1px;
    right: -1px;
    width: 8px;
    height: 8px;
    border-bottom: 1px solid var(--biolum);
    border-right: 1px solid var(--biolum);
}

.depth-label, .gauge-label {
    font-size: 0.6rem;
    color: var(--chrome-tert);
}
.depth-value, .gauge-value {
    font-size: 0.85rem;
    color: var(--chrome-primary);
    letter-spacing: 0.08em;
    font-variant-numeric: tabular-nums;
}

/* ============================================================
   AMBIENT CRYSTAL FIELD — drifting nodes in the void
   ============================================================ */

.ambient-field {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 2;
}

.ambient-node {
    position: absolute;
    width: 5px;
    height: 5px;
    background: var(--bg-mid);
    border: 1px solid var(--crystal-edge);
    transform: rotate(45deg);
    animation: ambient-drift 9s ease-in-out infinite;
}
.ambient-node:nth-child(2) { animation-delay: -1.5s; animation-duration: 11s; }
.ambient-node:nth-child(3) { animation-delay: -3s;   animation-duration: 8.5s; }
.ambient-node:nth-child(4) { animation-delay: -4.5s; animation-duration: 10s; }
.ambient-node:nth-child(5) { animation-delay: -6s;   animation-duration: 12s; }

@keyframes ambient-drift {
    0%, 100% { transform: rotate(45deg) translateY(0) scale(1); opacity: 0.25; }
    50%      { transform: rotate(135deg) translateY(-14px) scale(1.1); opacity: 0.7; }
}

/* ============================================================
   SHARED SECTION PRIMITIVES
   ============================================================ */

.section {
    position: relative;
    padding: 6rem 6vw 5rem 6vw;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.section--descent { min-height: 95vh; }
.section--floor   { min-height: 80vh; }

/* F-pattern grid: 35% / 10% gutter / 55% */
.f-grid {
    display: grid;
    grid-template-columns: 35% 10% 55%;
    gap: 0;
    align-items: start;
    margin-top: 3rem;
}

.f-heading   { grid-column: 1 / 2; }
.f-body      { grid-column: 3 / 4; }

/* ============================================================
   METALLIC TEXT
   ============================================================ */

.metal-text {
    background: linear-gradient(135deg,
        var(--chrome-secondary) 0%,
        var(--highlight-flare) 45%,
        var(--chrome-primary) 55%,
        var(--chrome-tert) 100%);
    background-size: 220% 220%;
    background-position: 0% 0%;
    -webkit-background-clip: text;
            background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    transition: background-position 900ms var(--ease-deep);
    display: inline-block;
}

.metal-text--soft {
    background: linear-gradient(135deg,
        var(--chrome-tert) 0%,
        var(--silver-hi) 50%,
        var(--chrome-secondary) 100%);
    -webkit-background-clip: text;
            background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}

/* ============================================================
   SECTION 1 — THE SURFACE (HERO)
   ============================================================ */

.section--surface {
    padding-top: 0;
    padding-bottom: 0;
    min-height: 100vh;
    overflow: hidden;
}

.surface-coords {
    position: absolute;
    top: 2.2rem;
    left: 6vw;
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    font-family: var(--f-mono);
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.18em;
    color: var(--dim-chrome);
}
.surface-coords .coord-line::before {
    content: '› ';
    color: var(--biolum);
}

.surface-content {
    position: absolute;
    top: 30%;
    left: 6vw;
    right: 6vw;
    transform: translateY(-20%);
    display: flex;
    flex-direction: column;
    gap: 1.4rem;
}

.surface-prelude {
    font-family: var(--f-mono);
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.22em;
    color: var(--biolum);
}

.hero-title {
    font-family: var(--f-display);
    font-weight: 300;
    font-size: clamp(3rem, 10vw, 9rem);
    letter-spacing: -0.03em;
    line-height: 1.05;
    color: var(--chrome-primary);
    display: flex;
    align-items: baseline;
    flex-wrap: wrap;
}

.hero-title .hero-word,
.hero-title .hero-dot {
    background: linear-gradient(135deg,
        var(--chrome-secondary) 0%,
        var(--highlight-flare) 45%,
        var(--chrome-primary) 55%,
        var(--chrome-tert) 100%);
    background-size: 220% 220%;
    background-position: var(--hero-pos, 0% 0%);
    -webkit-background-clip: text;
            background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    transition: background-position 1200ms var(--ease-deep);
}

.hero-title .hero-dot {
    font-family: var(--f-display);
    color: var(--biolum);
    -webkit-text-fill-color: var(--biolum);
    background: none;
    padding: 0 0.08em;
    position: relative;
    top: -0.1em;
    font-size: 0.7em;
}

.chrome-divider {
    position: relative;
    display: flex;
    align-items: center;
    height: 24px;
    width: 100%;
    max-width: 70%;
    margin-top: 1.2rem;
}

.chrome-divider--hero .divider-line {
    position: relative;
    height: 1px;
    width: 0%;
    background: linear-gradient(90deg,
        var(--chrome-primary) 0%,
        var(--chrome-secondary) 60%,
        transparent 100%);
    transition: width 1200ms var(--elastic) 200ms;
}

.chrome-divider--hero.is-ready .divider-line {
    width: 100%;
}

.sonar-pulse {
    position: absolute;
    right: -20px;
    top: 50%;
    width: 80px;
    height: 80px;
    transform: translate(0, -50%);
    pointer-events: none;
}

.sonar-core {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--biolum);
    box-shadow: 0 0 10px rgba(74, 124, 155, 0.8);
}

.sonar-ring {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    border: 1px solid var(--biolum);
    transform: translate(-50%, -50%) scale(0.4);
    opacity: 0;
    animation: sonar 3s cubic-bezier(0.25, 0.8, 0.3, 1) infinite;
}
.sonar-ring:nth-child(2) { animation-delay: 1s; }
.sonar-ring:nth-child(3) { animation-delay: 2s; }

@keyframes sonar {
    0%   { transform: translate(-50%, -50%) scale(0.4); opacity: 0.85; }
    80%  { opacity: 0.05; }
    100% { transform: translate(-50%, -50%) scale(4.8); opacity: 0; }
}

.surface-caption {
    font-family: var(--f-body);
    font-size: clamp(0.95rem, 1vw, 1.05rem);
    color: var(--silver-body);
    max-width: 40ch;
    margin-top: 0.8rem;
}

.surface-marker {
    position: absolute;
    left: 6vw;
    bottom: 5rem;
    display: flex;
    align-items: center;
    gap: 0.7rem;
    font-family: var(--f-mono);
    font-size: 0.65rem;
    text-transform: uppercase;
    letter-spacing: 0.2em;
    color: var(--chrome-tert);
}
.marker-tick {
    display: inline-block;
    width: 24px;
    height: 1px;
    background: var(--chrome-secondary);
}

.surface-scroll-hint {
    position: absolute;
    right: 6vw;
    bottom: 5rem;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 0.6rem;
    font-family: var(--f-mono);
    font-size: 0.65rem;
    text-transform: uppercase;
    letter-spacing: 0.22em;
    color: var(--dim-chrome);
}
.hint-arrow {
    width: 1px;
    height: 38px;
    background: linear-gradient(to bottom, var(--biolum), transparent);
    animation: hint-pulse 2.6s ease-in-out infinite;
}
@keyframes hint-pulse {
    0%, 100% { opacity: 0.4; transform: scaleY(1); transform-origin: top; }
    50%      { opacity: 1;   transform: scaleY(1.4); }
}

/* ============================================================
   SECTION MARKER (top strip of each descent section)
   ============================================================ */

.section-marker {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-family: var(--f-mono);
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.22em;
    color: var(--chrome-tert);
    margin-bottom: 1rem;
}
.marker-index {
    color: var(--biolum);
    font-weight: 400;
}
.marker-span {
    flex: 0 1 120px;
    height: 1px;
    background: linear-gradient(90deg, var(--crystal-edge), transparent);
}
.marker-title {
    color: var(--silver-hi);
    letter-spacing: 0.3em;
}

/* ============================================================
   SECTIONS 2–4 — THE DESCENT (F-pattern content)
   ============================================================ */

.section--descent {
    background: var(--bg-deep);
}

.f-heading {
    position: relative;
    padding-right: 2rem;
}

.heading-tag {
    display: inline-block;
    font-family: var(--f-mono);
    font-size: 0.7rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    color: var(--biolum);
    margin-bottom: 1rem;
}

.section-title {
    font-family: var(--f-display);
    font-weight: 600;
    font-size: clamp(1.8rem, 5vw, 4rem);
    letter-spacing: -0.02em;
    line-height: 1.1;
    margin-bottom: 1.2rem;
}

.heading-depth {
    display: inline-block;
    margin-top: 0.6rem;
    padding: 0.35rem 0.7rem;
    border: 1px solid var(--crystal-edge);
    font-family: var(--f-mono);
    font-size: 0.7rem;
    letter-spacing: 0.12em;
    color: var(--chrome-secondary);
    background: rgba(17, 17, 25, 0.6);
}

.f-body {
    position: relative;
}

.body-lede {
    font-family: var(--f-display);
    font-weight: 300;
    font-size: clamp(1.15rem, 1.6vw, 1.55rem);
    line-height: 1.45;
    letter-spacing: -0.01em;
    color: var(--silver-hi);
    margin-bottom: 1.4rem;
}

.body-lede .emph {
    color: var(--highlight-flare);
    font-style: italic;
    font-weight: 400;
    position: relative;
}
.body-lede .emph::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: -2px;
    height: 1px;
    background: linear-gradient(90deg, var(--biolum), transparent);
}

.body-text {
    color: var(--silver-body);
    max-width: 60ch;
    margin-bottom: 1.8rem;
}

.body-readouts {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    gap: 0;
    border-top: 1px solid var(--crystal-edge);
    padding-top: 1.2rem;
    margin-top: 1rem;
}
.body-readouts li {
    flex: 1 1 140px;
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    padding: 0 1rem 0 0;
    border-right: 1px solid var(--crystal-edge);
    margin-right: 1rem;
    font-family: var(--f-mono);
    font-size: 0.72rem;
    letter-spacing: 0.1em;
}
.body-readouts li:last-child {
    border-right: none;
    margin-right: 0;
}
.readout-key {
    text-transform: uppercase;
    color: var(--chrome-tert);
    font-size: 0.6rem;
    letter-spacing: 0.18em;
}
.readout-val {
    color: var(--silver-hi);
    font-size: 0.85rem;
    font-variant-numeric: tabular-nums;
}

/* ============================================================
   CRYSTAL DIVIDER — between descent sections
   ============================================================ */

.crystal-divider {
    position: relative;
    width: 100%;
    height: 20px;
    margin-top: 4rem;
}

.crystal-divider .cd-line {
    position: absolute;
    top: 50%;
    left: 0;
    height: 1px;
    width: 0;
    background: linear-gradient(90deg,
        transparent 0%,
        var(--crystal-edge) 10%,
        var(--chrome-secondary) 50%,
        var(--crystal-edge) 90%,
        transparent 100%);
    transform: translateY(-50%);
    transition: width 800ms var(--elastic);
}

.crystal-divider.is-ready .cd-line {
    width: 100%;
}

.cd-node {
    position: absolute;
    top: 50%;
    width: 6px;
    height: 6px;
    background: var(--bg-mid);
    border: 1px solid var(--crystal-edge);
    transform: translate(-50%, -50%) rotate(45deg);
    transition: background 400ms var(--elastic),
                border-color 400ms var(--elastic),
                transform 400ms var(--elastic),
                box-shadow 400ms var(--elastic);
}

.cd-node::before,
.cd-node::after {
    content: '';
    position: absolute;
    background: var(--crystal-edge);
    height: 1px;
    width: 14px;
    top: 50%;
    left: 50%;
    transform-origin: left center;
    opacity: 0.5;
}
.cd-node::before { transform: translate(0, -50%) rotate(30deg); }
.cd-node::after  { transform: translate(0, -50%) rotate(-30deg); }

.cd-node.is-active {
    background: var(--highlight-flare);
    border-color: var(--highlight-flare);
    transform: translate(-50%, -50%) rotate(45deg) scale(1.4);
    box-shadow: 0 0 14px rgba(232, 236, 244, 0.6);
}

/* ============================================================
   SECTION 5 — THE TRENCH — Specimen showcase
   ============================================================ */

.section--trench {
    background: var(--bg-mid);
    padding: 7rem 6vw;
    position: relative;
}

.section--trench::before,
.section--trench::after {
    content: '';
    position: absolute;
    left: 6vw;
    right: 6vw;
    height: 1px;
    background: linear-gradient(90deg,
        transparent,
        var(--crystal-edge) 20%,
        var(--chrome-secondary) 50%,
        var(--crystal-edge) 80%,
        transparent);
}
.section--trench::before { top: 0; }
.section--trench::after  { bottom: 0; }

.trench-header {
    max-width: 720px;
    margin-bottom: 4rem;
}
.trench-index {
    font-family: var(--f-mono);
    font-size: 0.7rem;
    letter-spacing: 0.26em;
    text-transform: uppercase;
    color: var(--biolum);
}
.trench-title {
    font-family: var(--f-display);
    font-weight: 600;
    font-size: clamp(1.8rem, 5vw, 4rem);
    letter-spacing: -0.02em;
    line-height: 1.1;
    margin: 0.8rem 0 1rem;
}
.trench-sub {
    color: var(--silver-body);
    max-width: 52ch;
}

.specimen-field {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: 3rem;
    margin-top: 3rem;
}

.specimen {
    position: relative;
    width: min(26vw, 340px);
    aspect-ratio: 2 / 3;
    border: 1px solid var(--crystal-edge);
    background:
        radial-gradient(ellipse at 20% 30%, #1a1a24 0%, transparent 50%),
        radial-gradient(ellipse at 70% 60%, #15151f 0%, transparent 40%),
        radial-gradient(ellipse at 45% 80%, #1c1c28 0%, transparent 45%),
        linear-gradient(180deg, #141420 0%, #0f0f18 100%);
    box-shadow:
        inset 0 0 60px rgba(10, 10, 15, 0.85),
        0 20px 40px rgba(0, 0, 0, 0.35);
    padding: 1.6rem;
    color: var(--silver-body);
    transition: transform 600ms var(--elastic),
                box-shadow 600ms var(--elastic),
                border-color 600ms var(--elastic);
    display: flex;
}

/* Minimum size safeguard on narrower viewports */
@media (max-width: 900px) {
    .specimen { width: min(70vw, 320px); }
}

.specimen-chrome {
    position: absolute;
    inset: 0;
    pointer-events: none;
    border: 1px solid transparent;
    border-image: linear-gradient(to bottom,
        var(--biolum) 0%,
        var(--crystal-edge) 50%,
        var(--biolum) 100%) 1;
}

.specimen-chrome::before,
.specimen-chrome::after {
    content: '';
    position: absolute;
    width: 14px;
    height: 14px;
    border-color: var(--chrome-primary);
}
.specimen-chrome::before {
    top: -1px; left: -1px;
    border-top: 1px solid var(--chrome-primary);
    border-left: 1px solid var(--chrome-primary);
}
.specimen-chrome::after {
    bottom: -1px; right: -1px;
    border-bottom: 1px solid var(--chrome-primary);
    border-right: 1px solid var(--chrome-primary);
}

.specimen-inner {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    gap: 0.7rem;
    width: 100%;
    text-align: left;
}

.specimen-tag {
    font-family: var(--f-mono);
    font-size: 0.65rem;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--biolum);
}

.specimen-name {
    font-family: var(--f-display);
    font-weight: 600;
    font-size: clamp(1.4rem, 2.2vw, 1.9rem);
    letter-spacing: -0.015em;
    line-height: 1.1;
    color: var(--chrome-primary);
    background: linear-gradient(135deg,
        var(--chrome-secondary) 0%,
        var(--highlight-flare) 50%,
        var(--chrome-primary) 100%);
    -webkit-background-clip: text;
            background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}

.specimen-depth {
    font-family: var(--f-mono);
    font-size: 0.7rem;
    letter-spacing: 0.14em;
    color: var(--silver-body);
    align-self: flex-start;
    padding: 0.2rem 0.55rem;
    border: 1px solid var(--crystal-edge);
}

.specimen-divider {
    height: 1px;
    width: 40%;
    background: linear-gradient(90deg, var(--biolum), transparent);
    margin: 0.4rem 0;
}

.specimen-desc {
    font-family: var(--f-body);
    font-size: 0.82rem;
    line-height: 1.65;
    color: var(--silver-body);
    flex: 1 1 auto;
}

.specimen-stats {
    margin-top: auto;
    padding-top: 0.9rem;
    border-top: 1px solid var(--crystal-edge);
    display: flex;
    flex-direction: column;
    gap: 0.35rem;
    font-family: var(--f-mono);
    font-size: 0.7rem;
}
.specimen-stats div {
    display: flex;
    justify-content: space-between;
    gap: 0.6rem;
}
.specimen-stats dt {
    text-transform: uppercase;
    letter-spacing: 0.16em;
    color: var(--chrome-tert);
    font-size: 0.6rem;
}
.specimen-stats dd {
    color: var(--silver-hi);
    font-variant-numeric: tabular-nums;
}

/* Elastic hover — 3% vertical stretch with spring settle */
.specimen:hover {
    transform: scaleY(1.03) translateY(-4px);
    border-color: var(--biolum);
    box-shadow:
        inset 0 0 80px rgba(10, 10, 15, 0.7),
        0 30px 60px rgba(0, 0, 0, 0.55),
        0 0 30px rgba(74, 124, 155, 0.2);
}

.trench-rule {
    margin-top: 4rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    font-family: var(--f-mono);
    font-size: 0.65rem;
    letter-spacing: 0.22em;
    text-transform: uppercase;
    color: var(--chrome-tert);
}
.rule-line {
    flex: 1 1 auto;
    height: 1px;
    background: linear-gradient(90deg, var(--crystal-edge), transparent);
}

/* ============================================================
   SECTION 6 — THE FLOOR (closing)
   ============================================================ */

.section--floor {
    background: var(--bg-floor);
    padding: 8rem 6vw;
    min-height: 80vh;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    text-align: right;
    position: relative;
}

.floor-frame {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 1.2rem;
    max-width: 640px;
}

.floor-coord {
    font-family: var(--f-mono);
    font-size: 0.7rem;
    letter-spacing: 0.26em;
    text-transform: uppercase;
    color: var(--biolum);
}

.floor-phrase {
    font-family: var(--f-display);
    font-weight: 300;
    font-size: clamp(2.2rem, 6vw, 4.8rem);
    letter-spacing: -0.02em;
    line-height: 1.1;
    color: var(--chrome-primary);
}

.floor-translation {
    font-family: var(--f-body);
    font-style: italic;
    font-size: 0.95rem;
    color: var(--chrome-tert);
    letter-spacing: 0.02em;
}

.floor-diamond {
    width: 12px;
    height: 12px;
    margin-top: 1.4rem;
    background: var(--bg-floor);
    border: 1px solid var(--chrome-secondary);
    transform: rotate(45deg);
    animation: floor-pulse 4s ease-in-out infinite;
    box-shadow: 0 0 0 rgba(200, 205, 213, 0);
}

@keyframes floor-pulse {
    0%, 100% {
        opacity: 0.3;
        box-shadow: 0 0 0 rgba(200, 205, 213, 0);
    }
    50% {
        opacity: 0.8;
        box-shadow: 0 0 14px rgba(200, 205, 213, 0.35);
    }
}

/* ============================================================
   REVEAL ANIMATIONS — IntersectionObserver driven
   ============================================================ */

.reveal {
    opacity: 0;
    transition: opacity 900ms var(--ease-deep),
                transform 900ms var(--elastic);
    will-change: opacity, transform;
}

.reveal--left  { transform: translateX(-40px); }
.reveal--right { transform: translateX(40px); }
.reveal--up    { transform: translateY(30px); }

.reveal.is-visible {
    opacity: 1;
    transform: translate(0, 0);
}

.reveal--right.is-visible { transition-delay: 200ms; }

/* ============================================================
   RESPONSIVE
   ============================================================ */

@media (max-width: 900px) {
    .section { padding: 5rem 6vw; }

    .f-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    .f-heading, .f-body { grid-column: 1 / -1; }

    .depth-indicator { top: 1rem; right: 1rem; min-width: 140px; padding: 0.7rem 0.8rem; }
    .pressure-gauge  { bottom: 1rem; right: 1rem; min-width: 140px; padding: 0.7rem 0.8rem; }

    .specimen-field {
        align-items: flex-start;
    }
    .specimen { margin-left: 0 !important; }

    .surface-coords { top: 1rem; left: 1rem; }
    .surface-content { top: 35%; left: 6vw; right: 6vw; }

    .section--floor { justify-content: flex-start; text-align: left; }
    .floor-frame { align-items: flex-start; }
}