:root {
  --bg: #07111c;
  --bg-soft: #0a1724;
  --panel: #0f1f2e;
  --panel-2: #13283a;
  --text: #f5f8fb;
  --muted: #a9bac8;
  --accent: #d9ad67;
  --accent-light: #f0c982;
  --line: rgba(255, 255, 255, .12);
  --line-strong: rgba(255, 255, 255, .2);
  --good: #63c89b;
  --bad: #ef8b88;
  --warning: #f0c982;
  --shadow: 0 24px 70px rgba(0, 0, 0, .28);
}

* { box-sizing: border-box; }
html { background: var(--bg); scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top right, rgba(217, 173, 103, .14), transparent 31rem),
    radial-gradient(circle at 10% 85%, rgba(50, 111, 145, .12), transparent 28rem),
    var(--bg);
}
button { font: inherit; }
button:focus-visible, summary:focus-visible { outline: 3px solid rgba(217, 173, 103, .45); outline-offset: 3px; }

.screen { display: none; width: min(100%, 1080px); margin: 0 auto; padding: 28px 20px 56px; }
.screen.active { display: block; animation: fadeIn .28s ease; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(5px); } to { opacity: 1; transform: none; } }

.hero { min-height: 58vh; display: flex; flex-direction: column; justify-content: center; align-items: flex-start; }
.brand-mark { width: 62px; height: 62px; border: 1px solid var(--accent); border-radius: 18px; display: grid; place-items: center; color: var(--accent); font-weight: 750; letter-spacing: .08em; margin-bottom: 22px; box-shadow: inset 0 0 25px rgba(217, 173, 103, .08); }
.eyebrow { color: var(--accent); text-transform: uppercase; letter-spacing: .16em; font-size: .76rem; font-weight: 700; margin: 0 0 8px; }
h1 { font-size: clamp(3rem, 11vw, 6.5rem); line-height: .92; letter-spacing: -.055em; margin: 0; }
h1 sup { font-size: .26em; vertical-align: top; }
h2, h3, h4 { letter-spacing: -.018em; }
.hero-copy { max-width: 690px; color: var(--muted); font-size: clamp(1.05rem, 2.5vw, 1.35rem); line-height: 1.55; margin: 24px 0 22px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 24px; }
.algorithm-strip { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; color: var(--muted); font-size: .85rem; }
.algorithm-strip span { border: 1px solid var(--line); border-radius: 999px; padding: 7px 10px; background: rgba(255, 255, 255, .025); }
.algorithm-strip i { color: var(--accent); font-style: normal; }

.primary, .secondary, .back, .answer, .next { border-radius: 14px; padding: 14px 18px; border: 1px solid transparent; cursor: pointer; transition: transform .18s ease, border-color .18s ease, background .18s ease; }
.primary:hover, .next:hover, .secondary:hover, .back:hover { transform: translateY(-1px); }
.primary, .next { color: #1a1209; background: linear-gradient(135deg, var(--accent-light), var(--accent)); font-weight: 750; box-shadow: 0 12px 30px rgba(217, 173, 103, .15); }
.secondary, .back, .answer { color: var(--text); background: transparent; border-color: var(--line); }

.feature-grid, .library-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.feature-grid article, .library-grid article, .case-card, .clinical-card, .question-card, .result-card, .evolution-card, .algorithm-card { background: linear-gradient(145deg, rgba(19, 40, 58, .92), rgba(12, 27, 41, .92)); border: 1px solid var(--line); border-radius: 22px; box-shadow: var(--shadow); }
.feature-grid article, .library-grid article { padding: 22px; }
.feature-grid span, .case-number { color: var(--accent); font-size: .78rem; letter-spacing: .12em; text-transform: uppercase; }
.feature-grid h2, .library-grid h3 { margin: 12px 0 8px; }
.feature-grid p, .library-grid p, .case-card p, .clinical-card p { color: var(--muted); line-height: 1.55; margin: 0; }

.topbar { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 12px; margin-bottom: 24px; }
.topbar > div:nth-child(2) { text-align: center; }
.topbar h2 { margin: 0; }
.back { justify-self: start; padding: 10px 12px; }
.version-badge { justify-self: end; color: var(--accent); border: 1px solid rgba(217, 173, 103, .35); border-radius: 999px; padding: 7px 10px; font-size: .78rem; }

.case-list { display: grid; gap: 14px; }
.case-card { width: 100%; text-align: left; padding: 22px; display: flex; justify-content: space-between; gap: 20px; align-items: center; color: var(--text); }
.case-card.available { cursor: pointer; }
.case-card.available:hover { border-color: rgba(217, 173, 103, .5); transform: translateY(-2px); }
.case-card.locked { opacity: .55; }
.case-card h3 { font-size: 1.28rem; margin: 7px 0; }
.case-card-meta { display: flex; gap: 10px; align-items: center; }
.level { color: var(--muted); font-size: .75rem; border-left: 1px solid var(--line); padding-left: 10px; }
.status { border: 1px solid var(--line); border-radius: 999px; padding: 8px 11px; color: var(--muted); white-space: nowrap; }
.available .status { color: var(--accent); border-color: rgba(217, 173, 103, .45); }

.library-grid { grid-template-columns: repeat(2, 1fr); }
.algorithm-card { padding: 24px; margin-bottom: 16px; }
.algorithm-card h3 { margin: 4px 0 18px; }
.algorithm-flow { display: flex; align-items: center; flex-wrap: wrap; gap: 9px; }
.algorithm-step { display: inline-flex; align-items: center; gap: 8px; padding: 9px 11px; border: 1px solid var(--line); border-radius: 13px; color: var(--text); }
.algorithm-step b { color: var(--accent); }
.algorithm-flow i { font-style: normal; color: var(--accent); }
.algorithm-note { color: var(--muted); font-size: .86rem; line-height: 1.5; margin: 18px 0 0; }
.notice { margin-top: 16px; color: var(--muted); padding: 16px 18px; border-left: 3px solid var(--accent); background: rgba(217, 173, 103, .08); border-radius: 0 12px 12px 0; }

.score-box { justify-self: end; text-align: right; }
.score-box span { font-size: 1.75rem; color: var(--accent); display: block; font-weight: 750; }
.score-box small { color: var(--muted); }
.progress-meta { display: flex; justify-content: space-between; gap: 12px; color: var(--muted); font-size: .82rem; margin-bottom: 8px; }
.progress-wrap { height: 8px; background: rgba(255, 255, 255, .08); border-radius: 999px; overflow: hidden; margin-bottom: 24px; }
.progress-bar { width: 0; height: 100%; background: linear-gradient(90deg, var(--accent), var(--accent-light)); transition: width .32s ease; }

.sim-grid { display: grid; grid-template-columns: .92fr 1.08fr; gap: 18px; align-items: start; }
.clinical-card, .question-card, .result-card, .evolution-card { padding: 24px; }
.clinical-card h3, .question-card h3 { margin: 4px 0 12px; font-size: clamp(1.35rem, 3vw, 1.8rem); }
.lead { font-size: 1.02rem; }
.clinical-card h4, .evolution-card h4 { margin: 22px 0 10px; color: #dce7ee; }
.sticky-card { position: sticky; top: 18px; }
.trace-heading, .evolution-header { display: flex; justify-content: space-between; gap: 12px; align-items: flex-start; }
.trace-tag, .source-control { border: 1px solid rgba(217, 173, 103, .4); color: var(--accent); border-radius: 999px; padding: 7px 10px; font-size: .78rem; white-space: nowrap; }
.source-control.controlled { color: var(--good); border-color: rgba(99, 200, 155, .45); }
.trace-instruction { color: var(--muted); line-height: 1.5; }

.data-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.compact-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.data-item, .hemorrhage-item { background: rgba(255, 255, 255, .035); border: 1px solid var(--line); padding: 13px; border-radius: 14px; min-width: 0; }
.data-item small, .hemorrhage-item small, .teg-values small { color: var(--muted); display: block; margin-bottom: 3px; }
.data-item strong, .hemorrhage-item strong { font-size: 1.08rem; overflow-wrap: anywhere; }
.hemorrhage-grid { display: grid; grid-template-columns: 1.15fr 1.2fr 1fr; gap: 10px; }
.hemorrhage-item.cumulative { border-color: rgba(217, 173, 103, .35); }
.hemorrhage-item.cumulative strong { color: var(--accent-light); }

.teg-chart { width: 100%; margin: 15px 0 10px; border-radius: 16px; background: #07111c; border: 1px solid var(--line); }
.chart-axis { stroke: rgba(255, 255, 255, .16); stroke-width: 2; }
.chart-guide { stroke: rgba(217, 173, 103, .18); stroke-width: 1; stroke-dasharray: 5 6; }
.trace-line { fill: none; stroke: url(#traceGlow); stroke-width: 5; stroke-linecap: round; filter: drop-shadow(0 0 7px rgba(217, 173, 103, .18)); }
.chart-label { fill: #a9bac8; font-size: 15px; }
.teg-values { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin-top: 12px; }
.teg-values div { text-align: center; background: rgba(255, 255, 255, .035); border: 1px solid var(--line); border-radius: 12px; padding: 10px 8px; }
.teg-values strong { font-size: 1rem; }

.clinical-context { margin-top: 16px; border-top: 1px solid var(--line); padding-top: 12px; }
.clinical-context summary { cursor: pointer; color: var(--accent); }
.clinical-context p { margin: 12px 0; }
.question-count { color: var(--muted); font-size: .82rem; margin-bottom: 8px; }
.answers { display: grid; gap: 10px; }
.answer { text-align: left; width: 100%; display: grid; grid-template-columns: 34px 1fr; align-items: center; gap: 10px; }
.answer:hover { border-color: var(--accent); background: rgba(217, 173, 103, .045); }
.answer:disabled { cursor: default; opacity: 1; }
.answer-letter { width: 30px; height: 30px; display: grid; place-items: center; border-radius: 9px; background: rgba(255, 255, 255, .05); color: var(--muted); font-weight: 750; }
.answer.correct { border-color: var(--good); background: rgba(99, 200, 155, .1); }
.answer.correct .answer-letter { background: rgba(99, 200, 155, .18); color: #c9f4df; }
.answer.wrong { border-color: var(--bad); background: rgba(239, 139, 136, .1); }
.answer.wrong .answer-letter { background: rgba(239, 139, 136, .18); color: #ffd0ce; }
.answer.dimmed { opacity: .55; }
.feedback { margin-top: 16px; padding: 14px; border-radius: 14px; line-height: 1.5; }
.feedback.good { background: rgba(99, 200, 155, .12); color: #bff1da; }
.feedback.bad { background: rgba(239, 139, 136, .12); color: #ffd0ce; }
.next { margin-top: 14px; width: 100%; }

.evolution-card { max-width: 960px; margin: 0 auto; }
.comparison-grid { display: grid; grid-template-columns: 1fr auto 1fr; gap: 16px; align-items: center; margin-top: 22px; }
.comparison-grid section { background: rgba(255, 255, 255, .025); border: 1px solid var(--line); border-radius: 18px; padding: 16px; }
.comparison-grid section h4 { margin-top: 0; }
.comparison-arrow { color: var(--accent); font-size: 2rem; }
.cumulative-rule { margin-top: 16px; padding: 14px 16px; border: 1px solid rgba(217, 173, 103, .28); background: rgba(217, 173, 103, .07); border-radius: 14px; color: var(--muted); line-height: 1.5; }
.cumulative-rule strong { color: var(--accent-light); }

.result-card { text-align: center; max-width: 760px; margin: 0 auto; }
.result-card h3 { font-size: clamp(1.6rem, 4vw, 2.2rem); margin: 8px 0; }
.result-score { font-size: 3.6rem; color: var(--accent); font-weight: 800; line-height: 1; margin-top: 16px; }
.result-score small { font-size: 1.2rem; color: var(--muted); }
.result-band { display: inline-block; margin-top: 12px; padding: 8px 12px; border-radius: 999px; border: 1px solid rgba(217, 173, 103, .4); color: var(--accent-light); }
.result-summary { color: var(--muted); }
.debrief-box { text-align: left; background: rgba(255, 255, 255, .03); border: 1px solid var(--line); border-radius: 16px; padding: 18px; margin: 22px 0; }
.debrief-box h4 { margin: 0 0 10px; }
.debrief-box ul { margin: 0; padding-left: 20px; color: var(--muted); line-height: 1.6; }
.answer-review { text-align: left; display: grid; gap: 8px; }
.answer-review > div { display: grid; grid-template-columns: 32px 1fr; gap: 10px; align-items: start; padding: 10px; border: 1px solid var(--line); border-radius: 12px; }
.answer-review p { margin: 2px 0; color: var(--muted); font-size: .88rem; }
.review-icon { width: 28px; height: 28px; display: grid; place-items: center; border-radius: 50%; font-weight: 800; }
.review-icon.ok { color: var(--good); background: rgba(99, 200, 155, .12); }
.review-icon.miss { color: var(--bad); background: rgba(239, 139, 136, .12); }
.result-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; margin-top: 22px; }

.loading-card, .error-card { min-height: 180px; display: grid; place-items: center; align-content: center; gap: 10px; border: 1px solid var(--line); border-radius: 18px; color: var(--muted); text-align: center; padding: 24px; }
.loader { width: 32px; height: 32px; border: 3px solid rgba(255, 255, 255, .1); border-top-color: var(--accent); border-radius: 50%; animation: spin .8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }
.error-card strong { color: var(--bad); font-size: 1.1rem; }
.error-card p { margin: 0; }
.app-message { position: fixed; left: 50%; bottom: 22px; transform: translate(-50%, 20px); opacity: 0; pointer-events: none; background: #13283a; border: 1px solid var(--line); border-radius: 12px; padding: 11px 15px; box-shadow: var(--shadow); transition: .22s ease; }
.app-message.visible { opacity: 1; transform: translate(-50%, 0); }

@media (max-width: 820px) {
  .feature-grid, .library-grid, .sim-grid { grid-template-columns: 1fr; }
  .sticky-card { position: static; }
  .teg-values { grid-template-columns: repeat(3, 1fr); }
  .comparison-grid { grid-template-columns: 1fr; }
  .comparison-arrow { transform: rotate(90deg); justify-self: center; }
}

@media (max-width: 620px) {
  .screen { padding: 20px 14px 42px; }
  .topbar { grid-template-columns: auto 1fr auto; }
  .topbar > div:nth-child(2) { text-align: left; }
  .simulation-topbar { grid-template-columns: auto 1fr; }
  .simulation-topbar .score-box { grid-column: 2; justify-self: start; display: flex; gap: 7px; align-items: baseline; text-align: left; }
  .simulation-topbar .score-box span { font-size: 1.3rem; }
  .hero { min-height: 52vh; }
  .case-card { align-items: flex-start; flex-direction: column; }
  .status { align-self: flex-start; }
  .data-grid, .hemorrhage-grid { grid-template-columns: 1fr; }
  .teg-values { grid-template-columns: repeat(2, 1fr); }
  .algorithm-flow i { display: none; }
  .algorithm-step { width: 100%; }
}