:root {
  --paper: #f4efe6;
  --paper-2: #ebe4d6;
  --ink: #241c15;
  --ink-soft: #5c5349;
  --line: #ddd2c0;
  --card: #fffdf8;
  --accent: #c45c32;
  --accent-deep: #9a3f1d;
  --accent-soft: #f3d8cc;
  --learn: #2f5d50;
  --learn-soft: #d7ebe4;
  --exam: #3d4a7a;
  --exam-soft: #d9def0;
  --wrong: #a33b32;
  --wrong-soft: #f6d8d4;
  --good: #2f5d50;
  --good-soft: #d7ebe4;
  --warn: #9a6b12;
  --shadow: 0 18px 50px rgba(36, 28, 21, 0.08);
  --radius: 18px;
  font-synthesis: none;
}

* { box-sizing: border-box; }
html, body { margin: 0; min-height: 100%; }
body {
  font-family: "Source Sans 3", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, #f8e1d3 0%, transparent 55%),
    radial-gradient(900px 420px at 110% 0%, #dce8e2 0%, transparent 50%),
    var(--paper);
}

button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; opacity: 0.55; }

.boot { max-width: 640px; margin: 18vh auto; padding: 24px; }
.boot-kicker {
  letter-spacing: 0.22em;
  text-transform: uppercase;
  font-size: 12px;
  color: var(--accent);
  font-weight: 700;
}

.app-shell { min-height: 100vh; }

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 18px 28px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 253, 248, 0.72);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 20;
}
.brand { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
.brand-kicker {
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 700;
}
.brand h1 {
  font-family: Fraunces, serif;
  font-size: 22px;
  font-weight: 650;
  margin: 0;
  letter-spacing: -0.02em;
}
.brand p { margin: 0; color: var(--ink-soft); font-size: 13px; }

.top-actions { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }

.wrap {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 28px 0 80px;
}

.hero {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 22px;
  margin-bottom: 22px;
}
.hero-copy h2 {
  font-family: Fraunces, serif;
  font-size: clamp(32px, 5vw, 48px);
  line-height: 1.08;
  margin: 0 0 12px;
  letter-spacing: -0.03em;
}
.hero-copy p { margin: 0; color: var(--ink-soft); font-size: 17px; max-width: 56ch; }
.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
}
.stat {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px 16px;
  box-shadow: var(--shadow);
}
.stat b { display: block; font-family: Fraunces, serif; font-size: 26px; }
.stat span { color: var(--ink-soft); font-size: 12px; }

.panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 22px;
}
.panel + .panel { margin-top: 18px; }
.panel h3 {
  margin: 0 0 14px;
  font-family: Fraunces, serif;
  font-size: 22px;
}
.muted { color: var(--ink-soft); }
.tiny { font-size: 12px; color: var(--ink-soft); }

.mode-grid, .quick-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}
.mode-card, .quick-btn, .opt-card {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 16px;
  padding: 16px;
  text-align: left;
  transition: border-color 0.15s, transform 0.15s, box-shadow 0.15s;
}
.mode-card:hover, .quick-btn:hover, .opt-card:hover { transform: translateY(-1px); }
.mode-card.active-learn {
  border-color: var(--learn);
  background: linear-gradient(180deg, #f3faf7, #fff);
  box-shadow: 0 0 0 3px var(--learn-soft);
}
.mode-card.active-exam {
  border-color: var(--exam);
  background: linear-gradient(180deg, #f4f6fc, #fff);
  box-shadow: 0 0 0 3px var(--exam-soft);
}
.mode-card .eyebrow {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}
.mode-card h4 { margin: 6px 0 6px; font-size: 20px; font-family: Fraunces, serif; }
.mode-card p { margin: 0; color: var(--ink-soft); font-size: 14px; }
.learn-col .eyebrow { color: var(--learn); }
.exam-col .eyebrow { color: var(--exam); }

.row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: center;
}
.grow { flex: 1; }

label.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
  font-weight: 600;
}
label.field input, label.field select, .search {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 12px;
  padding: 10px 12px;
  min-width: 0;
}
.check {
  display: flex;
  gap: 8px;
  align-items: center;
  font-weight: 500;
  font-size: 14px;
}

.btn {
  border: 0;
  border-radius: 999px;
  padding: 10px 16px;
  font-weight: 650;
  background: var(--ink);
  color: #fff;
}
.btn.secondary {
  background: transparent;
  color: var(--ink);
  border: 1px solid var(--line);
}
.btn.ghost { background: transparent; color: var(--ink-soft); }
.btn.accent { background: var(--accent); }
.btn.learn { background: var(--learn); }
.btn.exam { background: var(--exam); }
.btn.warn { background: var(--wrong); }
.btn.lg { padding: 14px 22px; font-size: 16px; }

.domain-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 8px;
}
.domain-chip {
  display: flex;
  justify-content: space-between;
  gap: 8px;
  align-items: center;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 12px;
  padding: 10px 12px;
  text-align: left;
}
.domain-chip.on {
  border-color: var(--accent);
  background: var(--accent-soft);
}
.domain-chip small { color: var(--ink-soft); }

.picker {
  max-height: 440px;
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 14px;
}
.picker-row, .picker-head {
  display: grid;
  grid-template-columns: 28px 64px 1fr 110px;
  gap: 8px;
  align-items: center;
  padding: 9px 12px;
  border-bottom: 1px solid var(--line);
}
.picker-head {
  position: sticky;
  top: 0;
  background: var(--paper-2);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-weight: 700;
  color: var(--ink-soft);
}
.picker-row:last-child { border-bottom: 0; }
.picker-row .stem {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  font-size: 14px;
}
.tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 999px;
  padding: 2px 8px;
  font-size: 11px;
  font-weight: 700;
  background: var(--paper-2);
}
.tag.multi { background: var(--exam-soft); color: var(--exam); }
.tag.match { background: var(--accent-soft); color: var(--accent-deep); }
.code {
  font-family: "IBM Plex Mono", monospace;
  font-size: 12px;
  font-weight: 500;
}

.import-box {
  border: 1.5px dashed var(--line);
  border-radius: 16px;
  padding: 16px;
  background: #fffaf3;
}
.import-box.drag { border-color: var(--accent); background: var(--accent-soft); }
.notice {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 12px;
  background: var(--paper-2);
  font-size: 13px;
}
.notice.bad { background: var(--wrong-soft); }

.quiz-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 250px;
  gap: 18px;
  align-items: start;
}
.quiz-main { min-width: 0; }
.progress-track {
  height: 8px;
  background: var(--paper-2);
  border-radius: 99px;
  overflow: hidden;
  margin: 4px 0 16px;
}
.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #e08a55);
  width: 0;
}
.q-meta { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; margin-bottom: 10px; }
.stem {
  font-family: Fraunces, serif;
  font-size: clamp(20px, 2.4vw, 28px);
  line-height: 1.28;
  margin: 0 0 18px;
  letter-spacing: -0.02em;
}
.options { display: grid; gap: 10px; }
.option {
  display: grid;
  grid-template-columns: 36px 1fr;
  gap: 12px;
  align-items: start;
  padding: 14px 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: #fff;
  text-align: left;
}
.option .key {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-weight: 700;
  background: var(--paper-2);
}
.option.selected:not(.correct):not(.wrong) {
  border-color: var(--accent);
  background: #fff6f1;
  box-shadow: 0 0 0 3px var(--accent-soft);
}
.option.selected:not(.correct):not(.wrong) .key {
  background: var(--accent);
  color: #fff;
}
.option.correct { border-color: var(--good); background: var(--good-soft); }
.option.wrong { border-color: var(--wrong); background: var(--wrong-soft); }
.option.missed { border-style: dashed; border-color: var(--good); }

.match-table { display: grid; gap: 10px; }
.match-row {
  display: grid;
  grid-template-columns: 1fr 220px;
  gap: 12px;
  align-items: center;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: #fff;
}
.match-row select { width: 100%; }
.match-row.correct { background: var(--good-soft); border-color: var(--good); }
.match-row.wrong { background: var(--wrong-soft); border-color: var(--wrong); }

.explain {
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: 14px;
  background: var(--learn-soft);
  border: 1px solid #b7d5cb;
}
.explain.bad { background: var(--wrong-soft); border-color: #e3b3ad; }
.explain h4 { margin: 0 0 6px; }

.nav-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 6px;
}
.nav-dot {
  height: 34px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #fff;
  font-size: 12px;
  font-weight: 650;
}
.nav-dot.current { outline: 2px solid var(--ink); }
.nav-dot.answered { background: var(--exam-soft); }
.nav-dot.good { background: var(--good-soft); }
.nav-dot.bad { background: var(--wrong-soft); }
.nav-dot.flag { box-shadow: inset 0 -3px 0 var(--accent); }

.score-pills { display: flex; gap: 8px; flex-wrap: wrap; }
.pill {
  border-radius: 999px;
  padding: 6px 10px;
  font-size: 13px;
  font-weight: 650;
  background: var(--paper-2);
}
.pill.good { background: var(--good-soft); color: var(--good); }
.pill.bad { background: var(--wrong-soft); color: var(--wrong); }
.pill.exam { background: var(--exam-soft); color: var(--exam); }
.timer.warn { background: #fbe7c6; color: var(--warn); }
.timer.danger { background: var(--wrong-soft); color: var(--wrong); }

.footer-bar {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 18px;
}

.results-hero {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 24px;
  align-items: center;
}
.score-ring {
  width: 220px;
  height: 220px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: conic-gradient(var(--good) calc(var(--pct) * 1%), var(--paper-2) 0);
}
.score-ring inner, .score-ring .inner {
  width: 168px;
  height: 168px;
  border-radius: 50%;
  background: var(--card);
  display: grid;
  place-items: center;
  text-align: center;
}
.score-ring strong {
  font-family: Fraunces, serif;
  font-size: 40px;
  display: block;
  line-height: 1;
}
.pass { color: var(--good); font-weight: 700; }
.fail { color: var(--wrong); font-weight: 700; }

.domain-bar { margin: 10px 0; }
.domain-bar .label { display: flex; justify-content: space-between; font-size: 13px; margin-bottom: 4px; }
.bar {
  height: 10px;
  background: var(--paper-2);
  border-radius: 99px;
  overflow: hidden;
}
.bar span { display: block; height: 100%; background: var(--accent); }

.review-item {
  border-top: 1px solid var(--line);
  padding: 14px 0;
}
.review-item h4 { margin: 0 0 6px; font-size: 16px; }
.kbd {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  background: var(--paper-2);
  padding: 1px 5px;
  border-radius: 4px;
}

.hidden-file { display: none; }

@media (max-width: 900px) {
  .hero, .quiz-layout, .results-hero, .match-row, .mode-grid { grid-template-columns: 1fr; }
  .picker-row, .picker-head { grid-template-columns: 28px 52px 1fr; }
  .picker-row .tag { display: none; }
  .wrap { width: min(100% - 20px, 1180px); }
  .topbar { padding: 14px 16px; }
}