/* Ausgeology · Ore deposits (SACE Stage 2 Earth and Environmental Science)
   The shared lesson design system: one reading column (about 68 characters)
   inside a 1080px frame; models and scenes use the full frame. The first
   block is shared by every lesson; the lesson's own tokens and blocks follow. */

:root {
  --bg: #eef0ec;
  --surface: #fbfcfa;
  --surface-2: #e2e7e2;
  --ink: #1a2124;
  --ink-2: #4a565a;
  --line: #c6cec9;
  --accent: #1f5f8b;
  --accent-ink: #ffffff;
  --accent-soft: #d6e5ef;
  --ochre: #b4501c;
  --ochre-band: #a5481a;
  --ochre-soft: #f6e2d4;
  --carbon: #1d2124;
  --carbon-ink: #ffffff;
  --sp-atm: #5b9fd0;
  --sp-atm-soft: #d9ebf7;
  --sp-hyd: #1f6f8a;
  --sp-hyd-soft: #d2e7ec;
  --sp-bio: #4f8a35;
  --sp-bio-soft: #dcecd2;
  --sp-geo: #9a5a2b;
  --sp-geo-soft: #efdcc9;
  --good: #2b7449;
  --good-soft: #dcefe3;
  --bad: #b3261e;
  --bad-soft: #f7dedc;
  --focus: #d99a00;
  --pop-bg: #1a2124;
  --pop-ink: #f2f4f2;
  --shadow: 0 1px 2px rgba(20, 30, 34, 0.06), 0 8px 24px rgba(20, 30, 34, 0.07);
  /* chart roles (validated with the dataviz palette script) */
  --viz-surface: #fbfcfa;
  --viz-1: #2a78d6;
  --viz-2: #eb6834;
  --viz-3: #1baf7a;
  --viz-dim: #b9b8ae;
  --viz-grid: #e1e0d9;
  --viz-axis: #c3c2b7;
  --viz-muted: #6f6e68;
  /* type */
  --font-display: "Archivo", "Helvetica Neue", Arial, system-ui, sans-serif;
  --font-body: "Atkinson Hyperlegible Next", "Atkinson Hyperlegible", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "Atkinson Hyperlegible Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  --scale: 1;
  --radius: 12px;
  --steps: 10;
  --i-check: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M9.4 16.6 4.8 12l-1.6 1.6 6.2 6.2L21 8.2l-1.6-1.6z'/%3E%3C/svg%3E");
  --i-cross: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M18.4 4.2 12 10.6 5.6 4.2 4.2 5.6l6.4 6.4-6.4 6.4 1.4 1.4 6.4-6.4 6.4 6.4 1.4-1.4-6.4-6.4 6.4-6.4z'/%3E%3C/svg%3E");
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #111517;
    --surface: #182024;
    --surface-2: #212a2f;
    --ink: #e6ebeb;
    --ink-2: #a9b5b8;
    --line: #2f3a3f;
    --accent: #7fb9e4;
    --accent-ink: #0b1822;
    --accent-soft: #1d3446;
    --ochre: #ec8a52;
    --ochre-band: #a5481a;
    --ochre-soft: #3d2416;
    --carbon: #0b0e10;
    --carbon-ink: #f2f4f2;
    --sp-atm: #7fb6dc;
    --sp-atm-soft: #1b3447;
    --sp-hyd: #5aa6bf;
    --sp-hyd-soft: #163640;
    --sp-bio: #7fb861;
    --sp-bio-soft: #1f3618;
    --sp-geo: #c98a55;
    --sp-geo-soft: #3d2816;
    --good: #66c792;
    --good-soft: #17372a;
    --bad: #f38b84;
    --bad-soft: #43201e;
    --focus: #ffcc4d;
    --pop-bg: #e6ebeb;
    --pop-ink: #111517;
    --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.35);
    --viz-surface: #182024;
    --viz-1: #3987e5;
    --viz-2: #d95926;
    --viz-3: #199e70;
    --viz-dim: #5d6a6e;
    --viz-grid: #263034;
    --viz-axis: #3a464b;
    --viz-muted: #95a2a6;
    color-scheme: dark;
  }
}

:root[data-theme="dark"] {
  --bg: #111517;
  --surface: #182024;
  --surface-2: #212a2f;
  --ink: #e6ebeb;
  --ink-2: #a9b5b8;
  --line: #2f3a3f;
  --accent: #7fb9e4;
  --accent-ink: #0b1822;
  --accent-soft: #1d3446;
  --ochre: #ec8a52;
  --ochre-band: #a5481a;
  --ochre-soft: #3d2416;
  --carbon: #0b0e10;
  --carbon-ink: #f2f4f2;
  --sp-atm: #7fb6dc;
  --sp-atm-soft: #1b3447;
  --sp-hyd: #5aa6bf;
  --sp-hyd-soft: #163640;
  --sp-bio: #7fb861;
  --sp-bio-soft: #1f3618;
  --sp-geo: #c98a55;
  --sp-geo-soft: #3d2816;
  --good: #66c792;
  --good-soft: #17372a;
  --bad: #f38b84;
  --bad-soft: #43201e;
  --focus: #ffcc4d;
  --pop-bg: #e6ebeb;
  --pop-ink: #111517;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 8px 24px rgba(0, 0, 0, 0.35);
  --viz-surface: #182024;
  --viz-1: #3987e5;
  --viz-2: #d95926;
  --viz-3: #199e70;
  --viz-dim: #5d6a6e;
  --viz-grid: #263034;
  --viz-axis: #3a464b;
  --viz-muted: #95a2a6;
  color-scheme: dark;
}

/* ---------- base ---------- */
html { font-size: calc(100% * var(--scale)); -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 1.125rem;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
*, *::before, *::after { box-sizing: border-box; }
[hidden] { display: none !important; }
img, svg, canvas { max-width: 100%; }
a { color: var(--accent); text-underline-offset: 0.18em; }
button, input, select { font: inherit; color: inherit; }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
p { margin: 0; }
.ul { text-decoration: underline; text-decoration-thickness: 0.09em; text-underline-offset: 0.16em; text-decoration-skip-ink: none; }

.wrap {
  max-width: 1080px;
  margin-inline: auto;
  padding-left: max(16px, env(safe-area-inset-left, 0px));
  padding-right: max(16px, env(safe-area-inset-right, 0px));
}
.prose { max-width: 68ch; }
.prose > * + * { margin-top: 0.85em; }
.prose ul, .prose ol { padding-left: 1.3em; margin-bottom: 0; }
.prose li + li { margin-top: 0.4em; }
.small { font-size: 0.92rem; color: var(--ink-2); }
.visually-hidden {
  position: absolute !important; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap;
}

.skip {
  position: absolute; left: 12px; top: -60px; z-index: 100;
  background: var(--accent); color: var(--accent-ink); padding: 10px 16px; border-radius: 8px;
  font-weight: 700; text-decoration: none;
}
.skip:focus { top: 12px; }

/* ---------- header ---------- */
.site-head { background: var(--surface); border-bottom: 1px solid var(--line); }
.head-row { display: flex; align-items: center; flex-wrap: wrap; gap: 10px 18px; padding-block: 12px 10px; }
.brand {
  font-family: var(--font-display); font-weight: 800; font-stretch: 118%;
  font-size: 1.2rem; letter-spacing: -0.01em; line-height: 1;
}
.brand i { font-style: normal; color: var(--ochre); }
.back {
  display: inline-flex; align-items: center; gap: 4px;
  font-size: 0.92rem; font-weight: 600; text-decoration: none; margin-right: auto;
}
.back:hover { text-decoration: underline; }
.back svg { width: 18px; height: 18px; }
.tools { display: flex; gap: 6px; flex-wrap: wrap; }
.tool {
  display: inline-flex; align-items: center; gap: 6px;
  min-height: 40px; padding: 6px 12px; border-radius: 999px;
  border: 1.5px solid var(--line); background: var(--bg); color: var(--ink);
  font-size: 0.9rem; font-weight: 600; cursor: pointer;
}
.tool:hover { border-color: var(--accent); }
.tool svg { width: 18px; height: 18px; flex: none; }
.tool[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.tool-val { font-family: var(--font-mono); font-size: 0.78rem; font-weight: 500; }

.rail-nav { padding-block: 2px 12px; }
.rail { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(var(--steps, 10), minmax(0, 1fr)); gap: 4px; }
.rail-btn {
  width: 100%; display: grid; gap: 5px; padding: 4px 0; border: 0; background: none;
  text-align: left; cursor: pointer; color: var(--ink-2); border-radius: 4px;
}
.rail-bar { height: 6px; border-radius: 3px; background: var(--surface-2); transition: background-color 0.2s; }
.rail-btn:hover .rail-bar { background: var(--line); }
.rail-btn.is-done .rail-bar { background: var(--accent-soft); box-shadow: inset 0 0 0 1px var(--accent); }
.rail-btn[aria-current="step"] .rail-bar { background: var(--accent); box-shadow: none; }
.rail-t { font-family: var(--font-mono); font-size: 0.7rem; line-height: 1.25; letter-spacing: 0.02em; }
.rail-t b { display: block; font-weight: 600; color: var(--ink); }
.rail-btn[aria-current="step"] .rail-t { color: var(--ink); }
.rail-now { display: none; font-family: var(--font-mono); font-size: 0.8rem; color: var(--ink-2); margin-top: 6px; }
.rail-now b { color: var(--ink); font-weight: 600; }

/* ---------- screens ---------- */
.js .screen:not(.is-active) { display: none; }
.screen { padding-block: 36px 56px; }
.screen-inner { display: grid; gap: 28px; }
.screen-inner > *, .section > *, .hero > *, .checks > *, .lab-body > * { min-width: 0; }
.screen-head { display: grid; gap: 8px; }
.eyebrow {
  font-family: var(--font-mono); font-size: 0.8rem; letter-spacing: 0.09em;
  text-transform: uppercase; color: var(--ink-2);
}
.display {
  font-family: var(--font-display); font-weight: 800; font-stretch: 116%;
  letter-spacing: -0.015em; line-height: 1; margin: 0; text-wrap: balance;
}
h1.display { font-size: clamp(2.7rem, 1.3rem + 5.6vw, 5.4rem); line-height: 0.95; }
h2.display { font-size: clamp(2rem, 1.25rem + 2.8vw, 3.1rem); }
h2.display:focus, h1.display:focus { outline: none; }
h3 {
  font-family: var(--font-display); font-weight: 750; font-stretch: 108%;
  font-size: 1.32rem; line-height: 1.2; margin: 0; text-wrap: balance; letter-spacing: -0.005em;
}
.display .dot { color: var(--ochre); }
.lede { font-size: 1.28rem; line-height: 1.5; max-width: 60ch; }
.section { display: grid; gap: 14px; }

/* ---------- hero ---------- */
.hero { display: grid; gap: 20px; padding-bottom: 8px; }
.fig-tag {
  position: absolute; right: 8px; top: 8px; font-family: var(--font-mono); font-size: 0.66rem;
  letter-spacing: 0.06em; text-transform: uppercase; background: rgba(0, 0, 0, 0.45); color: #fff;
  padding: 2px 6px; border-radius: 4px;
}
.country {
  max-width: 76ch; background: var(--surface-2); border-radius: var(--radius);
  padding: 16px 18px; font-size: 1rem; display: grid; gap: 6px;
}
.country b { font-weight: 700; }

.goals { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 16px; align-items: start; }
.goal-card { background: var(--surface); border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px; display: grid; gap: 10px; align-content: start; }
.goal-card ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 8px; }
.goal-card li { display: grid; grid-template-columns: 26px minmax(0, 1fr); gap: 8px; align-items: start; line-height: 1.45; }
.sc-num {
  width: 24px; height: 24px; border-radius: 50%; display: grid; place-items: center;
  font-family: var(--font-mono); font-size: 0.75rem; font-weight: 600;
  border: 1.5px solid var(--accent); color: var(--accent); margin-top: 1px;
}
.label {
  font-family: var(--font-mono); font-size: 0.74rem; font-weight: 600; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--ink-2);
}

/* ---------- teaching blocks ---------- */
.key-idea {
  max-width: 68ch; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px 20px 18px; display: grid; gap: 6px;
}
.key-idea .label { display: inline-flex; align-items: center; gap: 8px; }
.key-idea .label::before { content: ""; width: 14px; height: 14px; border-radius: 3px; background: var(--accent); }
.key-idea p { font-size: 1.26rem; font-weight: 700; line-height: 1.4; }

.steps { list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; max-width: 72ch; counter-reset: step; }
.steps > li { display: grid; grid-template-columns: 34px minmax(0, 1fr); gap: 12px; align-items: start; counter-increment: step; }
.steps > li::before {
  content: counter(step); width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center;
  background: var(--ochre-band); color: #fff; font-family: var(--font-mono); font-weight: 600; font-size: 0.85rem; margin-top: 1px;
}
.table-wrap { overflow-x: auto; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); }
table { border-collapse: collapse; width: 100%; font-size: 1rem; line-height: 1.45; }
caption { text-align: left; padding: 12px 14px 0; font-weight: 700; }
th, td { text-align: left; vertical-align: top; padding: 10px 14px; border-bottom: 1px solid var(--line); }
thead th {
  font-family: var(--font-mono); font-size: 0.72rem; font-weight: 600; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--ink-2); background: var(--surface-2);
}
tbody tr:last-child > * { border-bottom: 0; }
tbody th { font-weight: 700; }
td.time, th.time { font-variant-numeric: tabular-nums; }

details.more { max-width: 72ch; border: 1px dashed var(--line); border-radius: var(--radius); padding: 0 18px; background: transparent; }
details.more > summary { cursor: pointer; padding: 14px 0; font-weight: 700; list-style: none; display: flex; align-items: center; gap: 10px; }
details.more > summary::-webkit-details-marker { display: none; }
details.more > summary::before {
  content: "+"; width: 22px; height: 22px; border-radius: 50%; display: grid; place-items: center; flex: none;
  border: 1.5px solid var(--accent); color: var(--accent); font-family: var(--font-mono); font-size: 0.95rem; line-height: 1;
}
details.more[open] > summary::before { content: "\2212"; }
details.more > .more-body { padding: 0 0 18px; display: grid; gap: 12px; }
details.reveal > summary { list-style: none; width: fit-content; }
details.reveal > summary::-webkit-details-marker { display: none; }
details.reveal[open] > summary { display: none; }
.tag-ext { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--ink-2); font-weight: 500; }

/* ---------- labs ---------- */
.lab { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; overflow: hidden; box-shadow: var(--shadow); }
.lab-head { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: baseline; gap: 4px 16px; padding: 14px 18px; border-bottom: 1px solid var(--line); }
.lab-head h3 { font-size: 1.15rem; }
.lab-head .label { color: var(--accent); }
.lab-body { padding: 16px 18px 18px; display: grid; gap: 14px; }
.lab-body > p.small { max-width: 72ch; }
.lab .canvas-light { background: #cfe3ec; }
.lab-controls { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.status {
  margin: 0; min-height: 3.3em; padding: 12px 14px; border-radius: 10px;
  background: var(--surface-2); font-size: 1rem; line-height: 1.5;
}
.model-note { font-size: 0.92rem; color: var(--ink-2); max-width: 75ch; }
.model-note b { color: var(--ink); }

.btn {
  display: inline-flex; align-items: center; gap: 8px; min-height: 44px; padding: 9px 16px;
  border-radius: 999px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink);
  font-size: 1rem; font-weight: 650; line-height: 1.2; cursor: pointer; text-align: left; text-decoration: none;
}
.btn:hover:not(:disabled) { border-color: var(--accent); }
.btn[aria-pressed="true"] { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }
.btn-primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.btn-primary:hover:not(:disabled) { filter: brightness(1.08); }
.btn svg { width: 18px; height: 18px; flex: none; }
.btn small { font-weight: 500; font-size: 0.82rem; opacity: 0.85; }

.slider-row { display: grid; grid-template-columns: auto minmax(0, 1fr) auto; gap: 12px; align-items: center; }
.slider-row .label { white-space: nowrap; }
input[type="range"] { width: 100%; accent-color: var(--ochre); height: 32px; cursor: pointer; }
.stage-name { font-family: var(--font-display); font-weight: 800; font-stretch: 112%; font-size: 1.3rem; }

/* ---------- checks for understanding ---------- */
.checks { display: grid; gap: 16px; }
.check {
  max-width: 780px; background: var(--surface); border: 1px solid var(--line); border-radius: 16px;
  padding: 18px 20px 20px; display: grid; gap: 12px;
}
.check-head { display: flex; justify-content: space-between; gap: 12px; }
.check-q { font-weight: 700; font-size: 1.12rem; line-height: 1.45; }
.check-opts { display: grid; gap: 8px; }
.opt {
  position: relative; display: block; width: 100%; text-align: left; cursor: pointer;
  padding: 12px 14px 12px 48px; border-radius: 12px; border: 1.5px solid var(--line);
  background: var(--bg); color: var(--ink); line-height: 1.45; font-size: 1.02rem;
}
.opt:hover:not(:disabled) { border-color: var(--accent); }
.opt::before {
  content: attr(data-letter); position: absolute; left: 13px; top: 11px; width: 24px; height: 24px;
  border-radius: 50%; border: 1.5px solid var(--ink-2); color: var(--ink-2);
  font-family: var(--font-mono); font-size: 0.78rem; font-weight: 600; line-height: 21px; text-align: center;
}
.opt.is-right { border-color: var(--good); background: var(--good-soft); }
.opt.is-wrong { border-color: var(--bad); background: var(--bad-soft); }
.opt.is-right::before, .opt.is-wrong::before { content: ""; border: 0; border-radius: 0; }
.opt.is-right::before { background: var(--good); -webkit-mask: var(--i-check) center / 22px no-repeat; mask: var(--i-check) center / 22px no-repeat; }
.opt.is-wrong::before { background: var(--bad); -webkit-mask: var(--i-cross) center / 20px no-repeat; mask: var(--i-cross) center / 20px no-repeat; }
.opt:disabled { cursor: default; }
.opt:disabled:not(.is-right):not(.is-wrong) { opacity: 0.6; }
.fb { padding: 12px 14px; border-radius: 10px; font-size: 1rem; line-height: 1.5; background: var(--surface-2); }
.fb.is-right { background: var(--good-soft); }
.fb.is-wrong { background: var(--bad-soft); }
.fb strong { font-weight: 800; }
.fb.is-right strong { color: var(--good); }
.fb.is-wrong strong { color: var(--bad); }

/* ---------- exit check and results ---------- */
.results { max-width: 820px; background: var(--surface); border: 1.5px solid var(--accent); border-radius: 16px; padding: 18px 20px; display: grid; gap: 12px; }
.results-score { font-family: var(--font-display); font-weight: 800; font-stretch: 112%; font-size: 2rem; line-height: 1.1; }
.sc-results { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
.sc-results li { display: grid; grid-template-columns: 28px minmax(0, 1fr); gap: 10px; align-items: start; line-height: 1.45; }
.sc-icon { width: 24px; height: 24px; border-radius: 50%; margin-top: 1px; }
.sc-icon.ok { background: var(--good); -webkit-mask: var(--i-check) center / 20px no-repeat; mask: var(--i-check) center / 20px no-repeat; }
.sc-icon.todo { border: 2px solid var(--line); }
.sc-review { font-size: 0.95rem; }
.offline { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 16px; align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 18px 20px; }
.offline-links { display: flex; flex-wrap: wrap; gap: 8px; }
.teacher { max-width: 80ch; }
.teacher .more-body h3 { font-size: 1.05rem; margin-top: 6px; }
.teacher blockquote { margin: 0; padding: 10px 14px; border-radius: 10px; background: var(--surface-2); font-style: italic; }
.teacher blockquote p { margin: 0; }
.teacher blockquote ul { margin: 6px 0 0; padding-left: 22px; display: grid; gap: 3px; }
.teacher ul { margin: 0; padding-left: 1.2em; display: grid; gap: 6px; }
.confirm-row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }

/* ---------- screen navigation ---------- */
.screen-nav { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; padding-top: 22px; border-top: 1px solid var(--line); }
.screen-nav .next { margin-left: auto; }
.screen-nav .btn { max-width: 100%; }

/* ---------- glossary ---------- */
.term { cursor: help; border-bottom: 2px dotted var(--accent); border-radius: 2px; }
.term:focus-visible { outline: 3px solid var(--focus); outline-offset: 1px; }
.term:hover, .term[aria-expanded="true"] { color: var(--accent); }
.term-pop {
  position: absolute; z-index: 60; width: max-content; max-width: min(340px, calc(100vw - 32px));
  background: var(--pop-bg); color: var(--pop-ink); border-radius: 12px; padding: 12px 14px 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25); font-size: 0.98rem; line-height: 1.45; display: grid; gap: 4px;
}
.term-pop b { font-size: 1.02rem; }
.term-pop button { justify-self: start; margin-top: 4px; background: none; border: 0; padding: 4px 0; color: inherit; text-decoration: underline; cursor: pointer; font-size: 0.9rem; }
dialog.glossary {
  border: 0; border-radius: 18px; padding: 0; width: min(680px, calc(100vw - 32px)); max-height: min(84vh, 760px);
  background: var(--surface); color: var(--ink); box-shadow: 0 20px 60px rgba(0, 0, 0, 0.35);
}
dialog.glossary::backdrop { background: rgba(10, 14, 16, 0.55); }
.gl-head { position: sticky; top: 0; display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 16px 20px; background: var(--surface); border-bottom: 1px solid var(--line); }
.gl-head h2 { font-family: var(--font-display); font-weight: 800; font-stretch: 112%; font-size: 1.5rem; margin: 0; }
.gl-list { margin: 0; padding: 12px 20px 20px; display: grid; gap: 12px; }
.gl-list dt { font-weight: 800; }
.gl-list dd { margin: 2px 0 0; color: var(--ink-2); line-height: 1.5; }

/* read aloud */
.is-reading { background: var(--accent-soft); box-shadow: 0 0 0 4px var(--accent-soft); border-radius: 4px; }

.site-foot { border-top: 1px solid var(--line); background: var(--surface); }
.site-foot .wrap { padding-block: 18px 24px; display: flex; flex-wrap: wrap; gap: 8px 20px; justify-content: space-between; font-size: 0.9rem; color: var(--ink-2); }

/* ---------- responsive ---------- */
@media (max-width: 760px) {
  .goals { grid-template-columns: minmax(0, 1fr); }
  .rail-t { display: none; }
  .rail-now { display: block; }
  .offline { grid-template-columns: minmax(0, 1fr); }
  .tool-label { display: none; }
  .tool { padding: 6px 10px; }
}
@media (max-width: 520px) {
  body { font-size: 1.0625rem; }
  .screen { padding-block: 26px 44px; }
  .lab-head, .lab-body { padding-left: 14px; padding-right: 14px; }
  .check { padding: 16px; }
  .slider-row { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
  .slider-row input { grid-column: 1 / -1; grid-row: 1; }
  .slider-row .hi { text-align: right; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; scroll-behavior: auto !important; }
}



/* ---------- Ore deposits (SACE Stage 2 Earth and Environmental Science): lesson tokens and blocks ----------
   Malachite green is the accent. The three jigsaw expert groups each keep one
   colour through the lesson: magma orange, water blue and ancient-ocean violet.
   Cross-sections use earthy scene colours with a dark-mode set of their own. */
:root {
  --accent: #17694f;
  --accent-ink: #ffffff;
  --accent-soft: #d6ebe2;
  --ex-a: #b8501a; --ex-a-soft: #f8e3d6;
  --ex-b: #1d6f8f; --ex-b-soft: #d5eaf2;
  --ex-c: #6a4fa3; --ex-c-soft: #e6e0f3;
  /* 3D specimen tray */
  --tray: #1d2428; --tray-2: #2c363b; --tray-ink: #e8ecec; --tray-ink-2: #a3b3b8; --tray-line: #3a464c;
  /* scene colours for the cross-sections */
  --g-sky: #d8ebf5; --g-sky-2: #b3d5ea;
  --g-cover: #e8d8b6; --g-cover-2: #d9c39b; --g-cover-3: #c9ae80;
  --g-old: #c3b29d; --g-old-2: #ad9a83; --g-old-line: #8f7d68;
  --g-granite: #e6bcb0; --g-granite-2: #d69f93;
  --g-magma: #e4572e; --g-magma-2: #f39c3d; --g-magma-3: #fbd27a;
  --g-mafic: #4c5357; --g-mafic-2: #6a7276;
  --g-ore: #1f2326; --g-sulfide: #d9b23a; --g-gold: #f2c230;
  --g-vein: #f6f2e4; --g-fluid: #2a8fc0;
  --g-water: #3a93c4; --g-water-2: #1c5f8c; --g-foam: #ffffff;
  --g-soil: #7b5132; --g-bauxite: #c96f3b; --g-laterite: #a8492a; --g-saprolite: #e2c79c; --g-fresh: #8f8a83;
  --g-gravel: #b3a28a; --g-sand: #ead6a4; --g-silt: #cdb894; --g-bedrock: #8d857a;
  --g-jasper: #a3352a; --g-ironband: #4f555c; --g-sea: #3b7fa8; --g-sea-2: #1d4f73; --g-vent: #6b5a4c;
  --g-plant: #5b8a3c; --g-ink: #1a2124; --g-halo: rgba(255, 255, 255, 0.92); --g-panel: rgba(255, 255, 255, 0.94);
  --g-acid: #c98a1c; --g-rust: #c2601e; --g-clean: #3a93c4;
  --g-pit: #ddd1bf; --g-void: #3b3631;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --accent: #6fd0a7; --accent-ink: #052419; --accent-soft: #143528;
    --ex-a: #f08a52; --ex-a-soft: #3d2416; --ex-b: #6cc0de; --ex-b-soft: #12313d; --ex-c: #b49ae6; --ex-c-soft: #2a2140;
    --tray: #0b0f11; --tray-2: #1a2125; --tray-ink-2: #98a9ae; --tray-line: #2a3439;
    --g-sky: #213b4d; --g-sky-2: #182c3a;
    --g-cover: #6e6250; --g-cover-2: #5f5444; --g-cover-3: #514738;
    --g-old: #5b5246; --g-old-2: #4d453b; --g-old-line: #8a7b69;
    --g-granite: #8a6660; --g-granite-2: #765550;
    --g-magma: #e8613a; --g-magma-2: #f0a04a; --g-magma-3: #f7cf7d;
    --g-mafic: #2b3033; --g-mafic-2: #3e4549;
    --g-ore: #0d0f10; --g-sulfide: #cfa83a; --g-gold: #e9bb35;
    --g-vein: #d9d4c4; --g-fluid: #5ab0dc;
    --g-water: #2f6f99; --g-water-2: #173d58; --g-foam: #e8eef0;
    --g-soil: #5a3c25; --g-bauxite: #9a5630; --g-laterite: #7f3a22; --g-saprolite: #8f7b5d; --g-fresh: #5f5b56;
    --g-gravel: #7a6d5b; --g-sand: #a8946a; --g-silt: #8a7b60; --g-bedrock: #5c564f;
    --g-jasper: #8a2d24; --g-ironband: #6a7178; --g-sea: #2c5f80; --g-sea-2: #163a55; --g-vent: #4a3f35;
    --g-plant: #4a7432; --g-ink: #e6ebeb; --g-halo: rgba(17, 21, 23, 0.9); --g-panel: rgba(24, 32, 36, 0.95);
    --g-acid: #d9a03a; --g-rust: #d8743a; --g-clean: #5aa6d0;
    --g-pit: #6f6557; --g-void: #121517;
  }
}
:root[data-theme="dark"] {
  --accent: #6fd0a7; --accent-ink: #052419; --accent-soft: #143528;
  --ex-a: #f08a52; --ex-a-soft: #3d2416; --ex-b: #6cc0de; --ex-b-soft: #12313d; --ex-c: #b49ae6; --ex-c-soft: #2a2140;
  --tray: #0b0f11; --tray-2: #1a2125; --tray-ink-2: #98a9ae; --tray-line: #2a3439;
  --g-sky: #213b4d; --g-sky-2: #182c3a;
  --g-cover: #6e6250; --g-cover-2: #5f5444; --g-cover-3: #514738;
  --g-old: #5b5246; --g-old-2: #4d453b; --g-old-line: #8a7b69;
  --g-granite: #8a6660; --g-granite-2: #765550;
  --g-magma: #e8613a; --g-magma-2: #f0a04a; --g-magma-3: #f7cf7d;
  --g-mafic: #2b3033; --g-mafic-2: #3e4549;
  --g-ore: #0d0f10; --g-sulfide: #cfa83a; --g-gold: #e9bb35;
  --g-vein: #d9d4c4; --g-fluid: #5ab0dc;
  --g-water: #2f6f99; --g-water-2: #173d58; --g-foam: #e8eef0;
  --g-soil: #5a3c25; --g-bauxite: #9a5630; --g-laterite: #7f3a22; --g-saprolite: #8f7b5d; --g-fresh: #5f5b56;
  --g-gravel: #7a6d5b; --g-sand: #a8946a; --g-silt: #8a7b60; --g-bedrock: #5c564f;
  --g-jasper: #8a2d24; --g-ironband: #6a7178; --g-sea: #2c5f80; --g-sea-2: #163a55; --g-vent: #4a3f35;
  --g-plant: #4a7432; --g-ink: #e6ebeb; --g-halo: rgba(17, 21, 23, 0.9); --g-panel: rgba(24, 32, 36, 0.95);
  --g-acid: #d9a03a; --g-rust: #d8743a; --g-clean: #5aa6d0;
  --g-pit: #6f6557; --g-void: #121517;
}

.steps > li::before { background: var(--accent); }
input[type="range"] { accent-color: var(--accent); }

/* the phase chip on each screen head */
.phase { display: inline-flex; align-items: center; gap: 8px; width: fit-content; padding: 4px 12px 4px 6px; border-radius: 999px; background: var(--surface); border: 1px solid var(--line); font-size: 0.92rem; font-weight: 700; }
.phase i { min-width: 28px; height: 28px; padding: 0 6px; border-radius: 999px; display: grid; place-items: center; font-style: normal; font-family: var(--font-mono); font-size: 0.78rem; font-weight: 700; color: #fff; background: var(--accent); }
.phase.p-start i { background: #17694f; } .phase.p-home i { background: #8a5a12; } .phase.p-life i { background: #3d4852; } .phase.p-show i { background: #6c4fa8; }
.phase.p-a i { background: #b8501a; } .phase.p-b i { background: #1d6f8f; } .phase.p-c i { background: #6a4fa3; }
.inq-q { margin: 0; display: flex; gap: 10px; align-items: baseline; font-weight: 700; color: var(--ink-2); max-width: 70ch; }
.inq-q::before { content: "?"; flex: none; width: 24px; height: 24px; border-radius: 50%; display: grid; place-items: center; font-family: var(--font-mono); font-size: 0.8rem; color: var(--accent-ink); background: var(--accent); transform: translateY(2px); }

/* notebook boxes */
.note { display: grid; gap: 6px; max-width: 72ch; }
.note label, .note .field-label { font-weight: 700; line-height: 1.4; }
.note .hint { font-size: 0.95rem; color: var(--ink-2); font-weight: 400; margin: 0; }
.note textarea, .note input[type="text"] {
  width: 100%; border: 1.5px solid var(--line); border-radius: 10px; padding: 10px 12px; font: inherit; font-size: 1.04rem;
  color: var(--ink); background-color: var(--surface);
}
.note textarea {
  min-height: 6.4em; resize: vertical; line-height: 2rem; padding-top: 6px;
  background-image: repeating-linear-gradient(180deg, transparent 0 calc(2rem - 1px), var(--line) calc(2rem - 1px) 2rem);
  background-attachment: local; background-position: 0 6px;
}
.note textarea:focus, .note input:focus { border-color: var(--accent); outline: 2px solid var(--accent-soft); outline-offset: 0; }
.notebook { display: grid; gap: 16px; background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 18px 20px 20px; max-width: 820px; }
.notebook > h3 { display: flex; align-items: center; gap: 10px; }
.notebook > h3::before { content: ""; width: 20px; height: 22px; flex: none; border-radius: 3px 5px 5px 3px; background: var(--accent); box-shadow: inset 4px 0 0 rgba(255, 255, 255, 0.3); }
.readback { margin: 0; padding: 12px 14px; border-radius: 10px; background: var(--accent-soft); font-size: 1rem; line-height: 1.45; max-width: 72ch; }
.readback:empty { display: none; }
.key-idea p.label { font-size: 0.74rem; font-weight: 600; line-height: 1.3; }
.care { max-width: 76ch; margin: 0; padding: 12px 16px; border-radius: 12px; background: var(--surface-2); font-size: 0.98rem; line-height: 1.5; }

/* ---------- scenes ---------- */
.stage { position: relative; border-radius: 12px; overflow: hidden; background: var(--sc-sky); }
.stage svg { display: block; width: 100%; height: auto; }
.sc-text { font-family: var(--font-body); font-weight: 700; font-size: 17px; fill: var(--sc-ink); paint-order: stroke; stroke: var(--sc-halo); stroke-width: 5px; stroke-linejoin: round; text-anchor: middle; }
.sc-text-s { font-size: 14px; font-weight: 600; }
.sc-text-hero { font-size: 22px; stroke-width: 6px; }
.sc-text-hero.sc-text-s { font-size: 19px; }
.sc-start { text-anchor: start; } .sc-end { text-anchor: end; }
.sc-under { fill: #ffffff; stroke: rgba(10, 40, 60, 0.75); }
.sc-tag { font-family: var(--font-mono); font-size: 12px; letter-spacing: 0.06em; text-transform: uppercase; fill: var(--sc-ink); opacity: 0.8; }
.seg { display: inline-flex; flex-wrap: wrap; gap: 6px; padding: 4px; border-radius: 14px; background: var(--surface-2); width: fit-content; }
.seg button { min-height: 44px; padding: 8px 16px; border-radius: 10px; border: 0; background: transparent; color: var(--ink); font: inherit; font-weight: 700; cursor: pointer; }
.seg button[aria-pressed="true"] { background: var(--surface); box-shadow: 0 1px 3px rgba(0, 0, 0, 0.15); color: var(--accent); }
.seg button:focus-visible { outline: 3px solid var(--focus); outline-offset: 1px; }
.ctrl-row { display: flex; flex-wrap: wrap; gap: 10px 16px; align-items: center; }
.scroll-hint { display: none; }
@media (max-width: 700px) {
  .stage.scroll-x { overflow-x: auto; }
  .stage.scroll-x svg { min-width: 720px; }
  .scroll-hint { display: block; }
}
.legend { display: flex; flex-wrap: wrap; gap: 6px 16px; margin: 0; padding: 0; list-style: none; font-size: 0.94rem; color: var(--ink-2); }
.legend li { display: inline-flex; align-items: center; gap: 8px; }
.legend .sw { width: 14px; height: 14px; border-radius: 4px; flex: none; }
.legend .sw.moved { background: var(--sc-moved); }
.legend .sw.line-dash { width: 22px; height: 0; border-radius: 0; border-top: 2px dashed var(--sc-ink); }
.legend .sw.wall { background: var(--sc-rock); border: 1px solid var(--sc-rock-3); }
.legend .sw.sea { background: var(--sc-sea); }
.legend .sw.dot { border-radius: 50%; }
.legend .sw.line { height: 3px; width: 18px; border-radius: 2px; }
.pf-out { max-width: 820px; display: grid; gap: 8px; padding: 14px 16px; border-radius: 12px; background: var(--surface-2); }
.pf-out p { margin: 0; line-height: 1.5; }
.pf-nums { display: flex; flex-wrap: wrap; gap: 6px 18px; font-size: 0.96rem; color: var(--ink-2); }
.pf-nums b { color: var(--ink); font-variant-numeric: tabular-nums; }
/* ---------- charts ---------- */
.chart { display: grid; gap: 10px; }
.chart svg { display: block; width: 100%; height: auto; overflow: visible; max-width: 820px; }
.chart .c-title { font-weight: 700; margin: 0; }
.chart .c-sub { margin: 0; font-size: 0.94rem; color: var(--ink-2); }
.c-grid { stroke: var(--viz-grid); stroke-width: 1; }
.c-axis { stroke: var(--viz-axis); stroke-width: 1; }
.c-tick { font-family: var(--font-body); font-size: 13px; fill: var(--viz-muted); font-variant-numeric: tabular-nums; }
.c-lab { font-family: var(--font-body); font-size: 14px; font-weight: 700; fill: var(--ink); }
.c-lab-s { font-family: var(--font-body); font-size: 13px; fill: var(--ink-2); }
.c-val { font-family: var(--font-body); font-size: 13.5px; font-weight: 700; fill: var(--ink); font-variant-numeric: tabular-nums; }
.c-bar { fill: var(--viz-1); }
.c-bar2 { fill: var(--viz-2); }
.c-range { fill: var(--viz-1); fill-opacity: 0.28; stroke: var(--viz-1); stroke-width: 1.5; stroke-dasharray: 4 3; }
.c-hit { fill: transparent; cursor: pointer; }
.c-mark:focus { outline: none; }
.c-mark:focus-visible .c-focus, .c-mark:hover .c-focus, .c-mark.is-on .c-focus { stroke: var(--focus); stroke-width: 3; }
.c-focus { fill: none; stroke: transparent; }
.c-readout { margin: 0; min-height: 1.6em; font-size: 0.98rem; }
.tbl-num { text-align: right; font-variant-numeric: tabular-nums; }
details.tview { max-width: 820px; }
details.tview > summary { cursor: pointer; font-weight: 700; color: var(--accent); width: fit-content; padding: 6px 0; }
details.tview > summary:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; border-radius: 4px; }
details.tview[open] > summary { margin-bottom: 8px; }
.picks { display: flex; flex-wrap: wrap; gap: 6px; }
.rpick { min-height: 40px; padding: 6px 12px; border-radius: 999px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink); font: inherit; font-size: 0.92rem; font-weight: 700; cursor: pointer; }
.rpick:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.rpick.is-right { border-color: var(--good); background: var(--good-soft); }
.rpick.is-wrong { border-color: var(--bad); background: var(--bad-soft); }
.tl-item .fb, .icard .fb { font-size: 0.93rem; padding: 8px 10px; }
.chain { display: grid; gap: 8px; margin: 0; padding: 0; list-style: none; counter-reset: c; max-width: 820px; }
.chain li { counter-increment: c; display: grid; grid-template-columns: 34px minmax(0, 1fr); gap: 10px; align-items: start; padding: 10px 14px; border-radius: 12px; background: var(--accent-soft); }
.chain li::before { content: counter(c); width: 30px; height: 30px; border-radius: 50%; display: grid; place-items: center; font-family: var(--font-mono); font-size: 0.82rem; font-weight: 700; color: var(--accent-ink); background: var(--accent); }
.chain-pool { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 8px; }
.chain-pool button { text-align: left; padding: 12px 14px; border-radius: 12px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink); font: inherit; font-size: 0.96rem; line-height: 1.4; cursor: pointer; }
.chain-pool button:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.chain-pool button.is-wrong { border-color: var(--bad); background: var(--bad-soft); }
.icards { display: grid; grid-template-columns: repeat(auto-fill, minmax(270px, 1fr)); gap: 10px; }
.icard { display: grid; gap: 8px; padding: 12px 14px; border-radius: 14px; border: 1.5px solid var(--line); background: var(--surface); align-content: start; }
.icard p { margin: 0; font-size: 0.97rem; line-height: 1.45; }
.icard .yr { font-family: var(--font-mono); font-size: 0.74rem; letter-spacing: 0.05em; color: var(--ink-2); }
.icard.is-done { border-color: var(--good); }

/* ---------- step-through cross-sections ---------- */
.geo-stage { background: var(--g-old); }
.stp-bar { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 6px; }
.stp-btn { display: flex; align-items: center; gap: 8px; min-height: 46px; padding: 6px 10px; border-radius: 12px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink); font: inherit; font-weight: 700; font-size: 0.92rem; line-height: 1.2; cursor: pointer; text-align: left; }
.stp-btn i { flex: none; width: 26px; height: 26px; border-radius: 50%; display: grid; place-items: center; font-style: normal; font-family: var(--font-mono); font-size: 0.78rem; background: var(--surface-2); }
.stp-btn.is-past i { background: var(--accent-soft); color: var(--accent); }
.stp-btn[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); }
.stp-btn[aria-pressed="true"] i { background: var(--accent); color: var(--accent-ink); }
.stp-btn:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.stp-out { max-width: 820px; display: grid; gap: 6px; padding: 14px 16px; border-radius: 12px; background: var(--surface-2); min-height: 7.6em; }
.stp-out h4 { margin: 0; font-size: 1.08rem; }
.stp-out p { margin: 0; line-height: 1.55; }
.stp-nav { display: flex; flex-wrap: wrap; gap: 8px; justify-content: space-between; max-width: 820px; }

/* scene pieces shared by the cross-sections */
.g-sky { fill: var(--g-sky); }
.g-old { fill: var(--g-old); } .g-old2 { fill: var(--g-old-2); }
.g-oldline { fill: none; stroke: var(--g-old-line); stroke-width: 1.2; opacity: 0.35; }
.g-cover { fill: var(--g-cover); } .g-cover2 { fill: var(--g-cover-2); } .g-cover3 { fill: var(--g-cover-3); }
.g-surface { fill: none; stroke: var(--g-soil); stroke-width: 3; }
.g-tag { font-family: var(--font-mono); font-size: 13px; letter-spacing: 0.07em; text-transform: uppercase; fill: var(--g-ink); opacity: 0.85; }
.g-lab { font-family: var(--font-body); font-weight: 700; font-size: 17px; fill: var(--g-ink); paint-order: stroke; stroke: var(--g-halo); stroke-width: 5px; stroke-linejoin: round; }
.g-lab-s { font-family: var(--font-body); font-weight: 600; font-size: 14.5px; fill: var(--g-ink); paint-order: stroke; stroke: var(--g-halo); stroke-width: 4.5px; stroke-linejoin: round; }
.g-lead { fill: none; stroke: var(--g-ink); stroke-width: 1.5; opacity: 0.8; }
.g-arrowhead { fill: var(--g-ink); }
.g-arrow-soft { fill: none; stroke: var(--g-magma-3); stroke-width: 3; stroke-dasharray: 8 7; opacity: 0.9; }
.st-magma { stop-color: var(--g-magma); } .st-magma2 { stop-color: var(--g-magma-2); } .st-magma3 { stop-color: var(--g-magma-3); }
.g-chamber-edge { fill: none; stroke: var(--g-old-line); stroke-width: 3; }
.g-solid { fill: var(--g-mafic-2); transition: opacity 0.6s; }
.g-band-dark { fill: var(--g-ore); }
.g-band-pale { fill: #d9d2c3; opacity: 0.92; }
.g-band-top { fill: var(--g-mafic-2); }
.g-xtal-dark { fill: var(--g-ore); stroke: #000; stroke-width: 0.6; }
.g-xtal-pale { fill: #f3efe4; stroke: #8a8070; stroke-width: 0.6; }
.g-magma-body { fill: var(--g-magma); stroke: var(--g-magma-2); stroke-width: 3; transition: fill 0.6s; }
.g-granite-body { fill: var(--g-granite); stroke: var(--g-granite-2); stroke-width: 3; transition: fill 0.6s; }
.g-granite-speck { transition: opacity 0.6s; }
.g-sp-dark { fill: #2a2a2a; opacity: 0.75; } .g-sp-white { fill: #fbf8f2; opacity: 0.8; } .g-sp-pink { fill: #c98579; opacity: 0.8; }
.g-crack { fill: none; stroke: var(--g-old-line); stroke-width: 2; stroke-dasharray: 5 4; transition: opacity 0.4s; }
.g-vein { fill: none; stroke: var(--g-vein); stroke-width: 7; stroke-linejoin: round; stroke-linecap: round; transition: opacity 0.6s; }
.g-fluidline { fill: none; stroke: var(--g-fluid); stroke-width: 3; stroke-dasharray: 10 10; stroke-linecap: round; transition: opacity 0.4s; }
.g-fluidhead { fill: var(--g-fluid); }
.g-fluiddot { fill: var(--g-fluid); stroke: #fff; stroke-width: 1; }
.g-gold { fill: var(--g-gold); stroke: #7a5a00; stroke-width: 1; }
.g-sulfide { fill: var(--g-sulfide); stroke: #6a5410; stroke-width: 1; }
.g-headframe { fill: none; stroke: var(--g-ink); stroke-width: 2.4; stroke-linejoin: round; }
.g-shaft { fill: none; stroke: var(--g-ink); stroke-width: 5; opacity: 0.75; }
.g-temp { fill: none; stroke: var(--g-fluid); stroke-width: 4; stroke-linecap: round; }
@media (max-width: 520px) { .stp-bar { grid-template-columns: repeat(2, minmax(0, 1fr)); } }
.g-heat { fill: none; stroke: var(--g-magma); stroke-width: 3; stroke-linecap: round; }
.g-heathead { fill: var(--g-magma); }
.g-sinkarrow { fill: none; stroke: #ffffff; stroke-width: 2.4; stroke-linecap: round; }
.g-wheel { fill: none; stroke: var(--g-ink); stroke-width: 2.4; }
/* weathering profile */
.g-sun { fill: #f6c445; }
.g-cloud { fill: #ffffff; opacity: 0.92; }
.g-rainline { fill: none; stroke: var(--g-water); stroke-width: 2; stroke-linecap: round; opacity: 0.8; }
.g-freshrock { fill: var(--g-fresh); }
.g-joint { fill: none; stroke: #000; stroke-width: 1.2; opacity: 0.18; }
.g-clay { fill: var(--g-saprolite); transition: opacity 0.6s; }
.g-baux { fill: var(--g-bauxite); transition: opacity 0.6s; }
.g-piso { fill: #e2a46c; stroke: var(--g-laterite); stroke-width: 1.6; transition: opacity 0.6s; }
.g-topsoil { fill: var(--g-soil); }
.g-tree { fill: none; stroke: #6b4a2f; stroke-width: 3; stroke-linecap: round; }
.g-crown { fill: var(--g-plant); }
/* stream model */
.pl-stage { background: var(--g-sand); }
.pl-land { fill: #c9c08f; }
.pl-bush { fill: var(--g-plant); opacity: 0.55; }
.pl-gravel { fill: var(--g-gravel); }
.pl-water { fill: var(--g-water); opacity: 0.88; }
.pl-crack { fill: none; stroke: #263238; stroke-width: 3; stroke-linecap: round; opacity: 0.75; }
.pl-boulder { fill: var(--g-bedrock); stroke: #3d3a35; stroke-width: 2; }
.pl-flowarrow { fill: none; stroke: #ffffff; stroke-width: 3; stroke-linecap: round; opacity: 0.85; }
.pl-gold { fill: var(--g-gold); stroke: #6b4e00; stroke-width: 1.2; }
.pl-sand { fill: #f4ead2; stroke: #8a7a58; stroke-width: 0.8; }
.legend .sw.pl-sw-gold { background: var(--g-gold); border: 1px solid #6b4e00; }
.legend .sw.pl-sw-sand { background: #f4ead2; border: 1px solid #8a7a58; }
.legend .sw.pl-sw-crack { height: 3px; width: 18px; background: #263238; border-radius: 2px; }
.pl-out { max-width: 820px; display: grid; gap: 8px; padding: 14px 16px; border-radius: 12px; background: var(--surface-2); }
.pl-out p { margin: 0; line-height: 1.5; }
:root[data-theme="dark"] .pl-land { fill: #4a4733; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .pl-land { fill: #4a4733; } }
/* the ancient ocean */
.st-sea { stop-color: #5ea7c9; } .st-sea2 { stop-color: #1d4f73; }
:root[data-theme="dark"] .st-sea { stop-color: #2c6a8c; } :root[data-theme="dark"] .st-sea2 { stop-color: #10293c; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .st-sea { stop-color: #2c6a8c; } :root:not([data-theme="light"]) .st-sea2 { stop-color: #10293c; } }
.bif-ray { fill: none; stroke: #fff6c8; stroke-width: 8; opacity: 0.18; stroke-linecap: round; }
.bif-floor { fill: var(--g-vent); }
.bif-strom { fill: #3f6b3a; stroke: #29452a; stroke-width: 1.2; }
.bif-mats-on .bif-strom { fill: #5d9a45; }
.bif-vent { fill: #3a302a; stroke: #1f1915; stroke-width: 1.5; }
.bif-plume { fill: #9fb3a6; opacity: 0.45; }
.bif-o2 { fill: #ffffff; opacity: 0.9; transition: opacity 0.5s; }
.bif-fe { fill: #b9d4b8; stroke: #5b7b5a; stroke-width: 0.8; }
.bif-oxide { fill: #c0462f; stroke: #6e1f12; stroke-width: 0.8; }
.bif-ironband { fill: #a8392a; }
.bif-chert { fill: #d9d2c6; }
.bif-insetbox { fill: var(--g-panel); stroke: var(--line); stroke-width: 1.5; }
.bif-wall { fill: #8f3d2a; }
.bif-stripe-red { fill: none; stroke: #a23b28; stroke-width: 6; }
.bif-stripe-grey { fill: none; stroke: #5d6066; stroke-width: 5; }
.bif-pool { fill: var(--g-water); }
.bif-spinifex { fill: none; stroke: #b6a14a; stroke-width: 2.5; stroke-linecap: round; }

/* ---------- the opening picture ---------- */
.hero-fig { position: relative; margin: 0; border-radius: 18px; overflow: hidden; background: var(--g-sky); box-shadow: var(--shadow); }
.hero-fig svg { display: block; width: 100%; height: auto; }
.hero-fig figcaption { padding: 12px 16px 14px; background: var(--surface); border-top: 1px solid var(--line); font-size: 0.98rem; color: var(--ink-2); display: grid; gap: 8px; }
.hb-key { margin: 0; padding: 0; list-style: none; display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 4px 16px; color: var(--ink); }
.hb-key li { display: flex; gap: 8px; align-items: baseline; font-size: 0.95rem; line-height: 1.4; }
.hb-key b { flex: none; width: 24px; height: 24px; border-radius: 50%; display: inline-grid; place-items: center; font-family: var(--font-mono); font-size: 0.78rem; background: #fbf8f2; color: #1a2124; border: 2px solid #1a2124; }
.hb-key b.m { background: #1a2124; color: #fbf8f2; border-color: #fbf8f2; box-shadow: 0 0 0 1.5px #1a2124; }
.hb-sky1 { stop-color: #b9dbf0; } .hb-sky2 { stop-color: #e6f2f8; }
:root[data-theme="dark"] .hb-sky1 { stop-color: #10243a; } :root[data-theme="dark"] .hb-sky2 { stop-color: #23425a; }
@media (prefers-color-scheme: dark) { :root:not([data-theme="light"]) .hb-sky1 { stop-color: #10243a; } :root:not([data-theme="light"]) .hb-sky2 { stop-color: #23425a; } }
.hb-ground { fill: var(--g-old); }
.hb-surface { fill: none; stroke: var(--g-soil); stroke-width: 3; stroke-linejoin: round; }
.hb-gravel { fill: var(--g-gravel); }
.hb-river { fill: var(--g-water); }
.hb-vein { fill: none; stroke: var(--g-vein); stroke-width: 4; stroke-linejoin: round; stroke-linecap: round; }
.hb-pit { fill: var(--g-pit); stroke: var(--g-old-line); stroke-width: 2; stroke-linejoin: round; }
.hb-benchline, .mm-benchline { fill: none; stroke: var(--g-old-line); stroke-width: 1.5; opacity: 0.75; }
.hb-shaft { fill: none; stroke: var(--g-ink); stroke-width: 4; opacity: 0.78; }
.hb-chamber { stroke: var(--g-old-line); stroke-width: 2; }
.hb-well-in { fill: none; stroke: var(--g-fluid); stroke-width: 4; }
.hb-well-out { fill: none; stroke: var(--g-acid); stroke-width: 4; }
.hb-wellhead { fill: var(--g-ink); }
.hb-badge { fill: #fbf8f2; stroke: #1a2124; stroke-width: 2.5; }
.hb-badge.is-mine { fill: #1a2124; stroke: #fbf8f2; }
.hb-badge-t { font-family: var(--font-mono); font-size: 15px; font-weight: 700; fill: #1a2124; }
.is-mine + .hb-badge-t { fill: #fbf8f2; }

/* ---------- jigsaw: expert group chips and teach-back cards ---------- */
.groups { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; max-width: 980px; }
.grp { border-radius: 14px; padding: 14px 16px 16px; display: grid; gap: 6px; align-content: start; background: var(--surface); border: 1px solid var(--line); }
.grp h3 { font-size: 1.06rem; }
.grp p { margin: 0; font-size: 0.97rem; line-height: 1.5; }
.grp .label { color: var(--ink); }
.grp-a { border-top: 6px solid var(--ex-a); } .grp-b { border-top: 6px solid var(--ex-b); } .grp-c { border-top: 6px solid var(--ex-c); }
.teach { border-left: 6px solid var(--accent); }
.teach.grp-a { border-left-color: var(--ex-a); } .teach.grp-b { border-left-color: var(--ex-b); } .teach.grp-c { border-left-color: var(--ex-c); }
.notebook.teach { border-top: 1px solid var(--line); }
.teach.grp-a > h3::before { background: var(--ex-a); } .teach.grp-b > h3::before { background: var(--ex-b); } .teach.grp-c > h3::before { background: var(--ex-c); }

/* ---------- cards for everyday resources, older uses and the cases ---------- */
.ucards { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 12px; }
.ucard { display: grid; gap: 6px; align-content: start; padding: 14px 16px; border-radius: 14px; background: var(--surface); border: 1px solid var(--line); }
.ucard h4 { margin: 0; font-size: 1.04rem; }
.ucard p { margin: 0; font-size: 0.97rem; line-height: 1.5; }
.ucard .where { font-family: var(--font-mono); font-size: 0.74rem; letter-spacing: 0.05em; text-transform: uppercase; color: var(--ink-2); }
.ucard .src { font-size: 0.82rem; color: var(--ink-2); }
.ucard.old { border-top: 6px solid #9a5a2b; }
.ucard.case { border-top: 6px solid var(--g-rust); }

/* ---------- 3D specimen trays and the bench ---------- */
.tray { background: radial-gradient(120% 90% at 50% 30%, var(--tray-2), var(--tray) 72%); color: var(--tray-ink); border-radius: 18px; overflow: hidden; display: grid; box-shadow: var(--shadow); }
.tray-head { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; padding: 14px 16px 0; font-family: var(--font-mono); font-size: 0.76rem; letter-spacing: 0.09em; text-transform: uppercase; color: var(--tray-ink-2); }
.tray-name { color: var(--tray-ink); font-weight: 600; font-size: 0.86rem; }
.tray-stage { position: relative; aspect-ratio: 16 / 11; max-width: 100%; cursor: grab; touch-action: pan-y; }
.tray-stage:active { cursor: grabbing; }
.tray-stage canvas { display: block; width: 100%; height: 100%; outline: none; }
.tray-stage canvas:focus-visible { box-shadow: inset 0 0 0 3px var(--focus); border-radius: 12px; }
.tray-fallback { position: absolute; inset: 0; display: grid; place-items: center; padding: 24px; text-align: center; color: var(--tray-ink-2); font-size: 0.98rem; }
.tray-fallback img { width: 60%; max-width: 260px; }
.tray-tools { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; padding: 4px 14px 12px; }
.btn-tray { display: inline-flex; align-items: center; gap: 7px; min-height: 40px; padding: 7px 13px; border-radius: 999px; border: 1.5px solid var(--tray-line); background: rgba(255, 255, 255, 0.04); color: var(--tray-ink); font-size: 0.92rem; font-weight: 650; cursor: pointer; }
.btn-tray:hover { border-color: var(--tray-ink-2); }
.btn-tray[aria-pressed="true"] { background: var(--tray-ink); color: var(--tray); border-color: var(--tray-ink); }
.btn-tray:disabled { opacity: 0.4; cursor: not-allowed; }
.btn-tray svg { width: 18px; height: 18px; }
.tray-hint { margin-left: auto; font-size: 0.84rem; color: var(--tray-ink-2); }
.bench-main { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); gap: 16px; align-items: start; }
.bench-tests { display: grid; gap: 10px; align-content: start; }
.testbtns { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 6px; }
.testbtn { display: grid; gap: 2px; text-align: left; padding: 8px 10px; border-radius: 12px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink); font: inherit; cursor: pointer; min-height: 56px; }
.testbtn b { font-size: 0.98rem; }
.testbtn span { font-size: 0.8rem; color: var(--ink-2); line-height: 1.3; }
.testbtn[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); }
.testbtn:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.tests-res { margin: 0; display: grid; gap: 8px; padding: 12px 14px; border-radius: 12px; background: var(--surface-2); min-height: 9em; }
.tests-res div { display: grid; grid-template-columns: 76px minmax(0, 1fr); gap: 8px; }
.tests-res dt { font-family: var(--font-mono); font-size: 0.74rem; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; color: var(--ink-2); padding-top: 3px; }
.tests-res dd { margin: 0; line-height: 1.45; font-size: 0.98rem; }
.tests-res .res-head { grid-template-columns: minmax(0, 1fr); gap: 0; padding-bottom: 6px; border-bottom: 1px solid var(--line); }
.tests-res .res-head dt { font-family: var(--font-display); font-weight: 800; font-stretch: 112%; font-size: 1.3rem; letter-spacing: 0; text-transform: none; color: var(--ink); padding: 0; }
.tests-res .res-head dd { font-size: 0.92rem; color: var(--ink-2); }
.tests-res .res-empty { grid-template-columns: minmax(0, 1fr); color: var(--ink-2); }
.thumbs { display: grid; grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); gap: 8px; }
.thumb { margin: 0; border-radius: 14px; padding: 8px 10px 10px; display: grid; gap: 4px; align-content: start; background: radial-gradient(110% 90% at 50% 30%, var(--tray-2), var(--tray) 75%); color: var(--tray-ink); border: 2px solid transparent; text-align: left; cursor: pointer; width: 100%; font: inherit; }
.thumb img { display: block; width: 100%; height: auto; aspect-ratio: 1; object-fit: contain; }
.thumb .cap { display: grid; gap: 1px; }
.thumb b { font-size: 0.95rem; }
.thumb span span { font-size: 0.8rem; line-height: 1.3; color: var(--tray-ink-2); }
.thumb:hover { border-color: var(--tray-ink-2); }
.thumb[aria-pressed="true"] { border-color: var(--focus); }
.thumb:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.my-opts { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px; }
.my-nav { display: flex; justify-content: space-between; gap: 8px; flex-wrap: wrap; }
.bif-tray { max-width: 560px; }

/* ---------- the survey ---------- */
.sv-brief { max-width: 72ch; margin: 0; line-height: 1.55; }
.sv-buttons { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 6px; }
.sv-btn { display: grid; gap: 2px; text-align: left; padding: 8px 12px; border-radius: 12px; border: 1.5px solid var(--line); background: var(--surface); color: var(--ink); font: inherit; cursor: pointer; min-height: 52px; }
.sv-btn span { font-size: 0.8rem; color: var(--ink-2); }
.sv-btn[aria-pressed="true"] { border-color: var(--accent); background: var(--accent-soft); }
.sv-btn:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.sv-what { max-width: 76ch; margin: 0; padding: 12px 14px; border-radius: 12px; background: var(--surface-2); line-height: 1.5; min-height: 3.2em; }
.sv-wrap { display: grid; grid-template-columns: minmax(0, 2.2fr) minmax(0, 1fr); gap: 16px; align-items: start; }
.sv-map svg { display: block; width: 100%; height: auto; border-radius: 10px; background: var(--surface-2); }
.sv-map svg:focus-visible { outline: 3px solid var(--focus); outline-offset: 2px; }
.sv-cell { cursor: crosshair; transition: fill 0.25s; }
.sv-cell.is-blank { fill: var(--surface); }
.sv-axis { font-family: var(--font-mono); font-size: 12px; fill: var(--ink-2); }
.sv-cursor { fill: none; stroke: var(--focus); stroke-width: 3.5; pointer-events: none; }
.sv-hover { fill: none; stroke: var(--ink-2); stroke-width: 1.5; stroke-dasharray: 4 3; pointer-events: none; }
.sv-hole { fill: #ffffff; stroke: #1a2124; stroke-width: 2.5; }
.sv-hole.is-ore { fill: var(--g-gold); }
.sv-holenum { font-family: var(--font-mono); font-size: 13px; font-weight: 700; fill: #1a2124; pointer-events: none; }
.sv-side { display: grid; gap: 10px; align-content: start; }
.sv-legend { display: grid; gap: 4px; }
.sv-bar { display: block; height: 14px; border-radius: 4px; border: 1px solid var(--line); }
.sv-ends { display: flex; justify-content: space-between; font-size: 0.86rem; color: var(--ink-2); font-variant-numeric: tabular-nums; }
.sv-read { margin: 0; padding: 10px 12px; border-radius: 10px; background: var(--surface-2); font-size: 0.97rem; line-height: 1.45; min-height: 4.5em; }
.sv-logs { list-style: none; margin: 0; padding: 0; display: grid; gap: 8px; max-width: 820px; }
.sv-log { display: grid; gap: 2px; padding: 10px 14px; border-radius: 12px; border: 1.5px solid var(--line); background: var(--surface); font-size: 0.97rem; line-height: 1.45; }
.sv-log.is-ore { border-color: var(--good); background: var(--good-soft); }
.sv-debrief { max-width: 820px; display: grid; gap: 8px; padding: 14px 16px; border-radius: 12px; background: var(--accent-soft); }
.sv-debrief h4 { margin: 0; font-size: 1.08rem; }
.sv-debrief p { margin: 0; line-height: 1.55; }

/* ---------- mining methods ---------- */
.mcards { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 12px; }
.mcard { display: grid; gap: 8px; align-content: start; padding: 14px 16px 16px; border-radius: 14px; background: var(--surface); border: 1px solid var(--line); }
.mcard svg { display: block; width: 100%; height: auto; border-radius: 10px; }
.mcard h4 { margin: 0; font-size: 1.08rem; }
.mcard ul { margin: 0; padding-left: 1.15em; display: grid; gap: 4px; font-size: 0.96rem; line-height: 1.45; }
.mcases { display: grid; gap: 12px; }
.mcase { display: grid; grid-template-columns: 300px minmax(0, 1fr); gap: 16px; align-items: start; padding: 14px 16px; border-radius: 14px; border: 1.5px solid var(--line); background: var(--surface); }
.mcase.is-done { border-color: var(--good); }
.mcase svg { display: block; width: 100%; height: auto; border-radius: 10px; }
.mcase-body { display: grid; gap: 8px; }
.mcase-body h4 { margin: 0; font-size: 1.08rem; }
.mcase-body p { margin: 0; line-height: 1.5; font-size: 0.98rem; }
.mc-layer { fill: none; stroke: var(--g-cover-3); stroke-width: 1.5; }
.mc-ore { fill: #7a2d22; stroke: #3d120c; stroke-width: 1.5; }
.mc-lode { fill: none; stroke: var(--g-gold); stroke-width: 4; stroke-linecap: round; }
.mc-clay { fill: #b9a98c; }
.mc-sand { fill: var(--g-sand); }
.mc-lab { font-family: var(--font-body); font-weight: 700; font-size: 14px; fill: var(--g-ink); paint-order: stroke; stroke: var(--g-halo); stroke-width: 4px; stroke-linejoin: round; }
.mc-lab-l { font-family: var(--font-body); font-weight: 700; font-size: 15px; fill: #ffffff; }
.mm-pit { fill: var(--g-pit); stroke: var(--g-old-line); stroke-width: 2; stroke-linejoin: round; }
.mm-truck { fill: #e9a83a; stroke: #1a2124; stroke-width: 1.2; }
.mm-shaft { fill: none; stroke: var(--g-ink); stroke-width: 5; opacity: 0.8; }
.mm-stope { fill: var(--g-void); stroke: var(--g-ink); stroke-width: 1.2; }
.mm-in { fill: none; stroke: var(--g-fluid); stroke-width: 4; }
.mm-out { fill: none; stroke: var(--g-acid); stroke-width: 4; }
.mm-flow { fill: none; stroke: var(--g-fluid); stroke-width: 2; stroke-dasharray: 5 4; }
.pit-stage { background: var(--g-old); }
.pit-hole { fill: var(--g-pit); stroke: var(--g-old-line); stroke-width: 2; }
.pit-ore { fill: #7a2d22; stroke: #3d120c; stroke-width: 1.5; }
.pit-bench { stroke: var(--g-old-line); stroke-width: 2; }
.pit-scale { stroke: var(--g-ink); stroke-width: 3; }
.pit-lab-l { font-family: var(--font-body); font-weight: 700; font-size: 16px; fill: #ffffff; }
.pit-nums { max-width: 820px; display: grid; gap: 8px; padding: 14px 16px; border-radius: 12px; background: var(--surface-2); }
.pit-nums p { margin: 0; line-height: 1.5; }
.sliders { display: grid; gap: 6px; max-width: 760px; }
.slider-row output { font-family: var(--font-mono); font-size: 0.9rem; min-width: 5.5ch; text-align: right; }
.sliders .slider-row { grid-template-columns: 10.5rem minmax(0, 1fr) 6ch; }
.pit-sw-waste { background: var(--g-pit); border: 1.5px solid var(--g-old-line); }
.pit-sw-ore { background: #7a2d22; }
.pit-sw-rock { background: var(--g-old); }

/* ---------- the footprint ---------- */
.ck-stage { background: var(--g-sky); }
.ck-dump { fill: #8d857a; stroke: #4e4943; stroke-width: 2; }
.ck-pyrite { fill: var(--g-sulfide); stroke: #6a5410; stroke-width: 0.8; }
.ck-seep { fill: none; stroke: var(--g-rust); stroke-width: 4; stroke-dasharray: 8 6; }
.ck-head { fill: var(--g-rust); }
.ck-plant { fill: #e6ebeb; stroke: #1a2124; stroke-width: 2; transition: opacity 0.4s; }
.ck-plantlab { font-family: var(--font-body); font-weight: 700; font-size: 14px; fill: #1a2124; }
.ck-creek { fill: none; stroke-width: 12; stroke-linecap: round; transition: stroke 0.5s; }
.ck-creek.is-acid { stroke: var(--g-acid); }
.ck-creek.is-clean { stroke: var(--g-clean); }
.ck-bed { fill: none; stroke: var(--g-old-2); stroke-width: 4; transition: stroke 0.5s; }
.ck-bed.is-orange { stroke: var(--g-rust); }
.ck-fish { fill: #3d4852; }
.ck-reed { fill: none; stroke: var(--g-plant); stroke-width: 2.4; stroke-linecap: round; }
.eq { font-family: var(--font-mono); font-size: 1rem; padding: 10px 14px; border-radius: 10px; background: var(--surface-2); overflow-x: auto; white-space: nowrap; }

/* ---------- how long will it last ---------- */
.calc { display: grid; gap: 10px; max-width: 820px; }
.calc-row { display: grid; gap: 8px; padding: 12px 14px; border-radius: 12px; background: var(--surface); border: 1px solid var(--line); }
.calc-row p { margin: 0; line-height: 1.5; }
.calc-in { display: flex; flex-wrap: wrap; gap: 8px 12px; align-items: center; }
.calc-in label { font-weight: 700; }
.calc-in input { width: 8.5em; border: 1.5px solid var(--line); border-radius: 10px; padding: 8px 10px; font: inherit; background: var(--bg); color: var(--ink); }
.calc-in input:focus { border-color: var(--accent); outline: 2px solid var(--accent-soft); }
.quote { margin: 0; max-width: 76ch; padding: 12px 16px; border-left: 4px solid var(--accent); background: var(--surface); border-radius: 0 12px 12px 0; line-height: 1.55; }
.quote cite { display: block; margin-top: 6px; font-style: normal; font-size: 0.86rem; color: var(--ink-2); }

@media (max-width: 860px) {
  .bench-main, .sv-wrap { grid-template-columns: minmax(0, 1fr); }
  .mcards { grid-template-columns: minmax(0, 1fr); }
  .groups { grid-template-columns: minmax(0, 1fr); }
  .mcase { grid-template-columns: minmax(0, 1fr); }
  .mcase svg { max-width: 360px; }
}
@media (max-width: 560px) {
  .sv-buttons { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .testbtns { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .my-opts { grid-template-columns: minmax(0, 1fr); }
  .tray-hint { margin-left: 0; }
}

/* the home group: the student's own teach-back card, shown again */
.tb-read { display: grid; gap: 12px; max-width: 820px; }
.tb-read:empty { display: none; }
.tb-card { background: var(--surface); border: 1px solid var(--line); border-left: 6px solid var(--accent); border-radius: 14px; padding: 14px 18px; }
.tb-card.is-empty { background: var(--accent-soft); border-color: transparent; border-left-color: var(--accent); }
.tb-card.grp-a { border-top: 1px solid var(--line); border-left-color: var(--ex-a); }
.tb-card.grp-b { border-top: 1px solid var(--line); border-left-color: var(--ex-b); }
.tb-card.grp-c { border-top: 1px solid var(--line); border-left-color: var(--ex-c); }
.tb-card p { margin: 0; }
.tb-card .small { margin-top: 6px; }
.tb-card dl { margin: 8px 0 0; display: grid; gap: 8px; }
.tb-card dt { font-weight: 700; font-size: 0.92rem; }
.tb-card dd { margin: 2px 0 0; white-space: pre-wrap; line-height: 1.45; }

@media (max-width: 520px) {
  .sliders .slider-row { grid-template-columns: minmax(0, 1fr) auto; }
}
/* phones: the diagrams keep a readable size and slide sideways */
@media (max-width: 700px) {
  .sv-map { overflow-x: auto; border-radius: 10px; }
  .sv-map svg { min-width: 600px; }
  .hero-scroll { overflow-x: auto; }
  .hero-scroll svg { min-width: 720px; }
  .hero-hint { margin: 6px 16px 0; }
  .geo-stage.scroll-x svg { min-width: 600px; }
}