:root {
  --bg: #fff8f0;
  --bg-card: #ffffff;
  --ink: #2d3436;
  --ink-soft: #636e72;
  --accent: #e76f51;
  --accent-2: #f4a261;
  --accent-3: #2a9d8f;
  --ok: #2a9d8f;
  --bad: #e76f51;
  --line: #f0e6d8;
  --shadow: 0 8px 24px rgba(45, 52, 54, 0.08);
  --radius: 16px;
  --font: "Segoe UI", system-ui, -apple-system, sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background:
    radial-gradient(1200px 400px at 10% -10%, #ffe8d6 0%, transparent 55%),
    radial-gradient(900px 320px at 100% 0%, #d8f3ef 0%, transparent 50%),
    var(--bg);
  min-height: 100vh;
  line-height: 1.45;
  -webkit-font-smoothing: antialiased;
}

.app {
  max-width: 430px;
  margin: 0 auto;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  padding: 0 14px 24px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 14px 0 10px;
  position: sticky;
  top: 0;
  z-index: 5;
  background: linear-gradient(180deg, var(--bg) 70%, transparent);
}

.brand {
  display: flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
  color: inherit;
}
.brand-emoji {
  font-size: 1.6rem;
  background: #fff;
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  box-shadow: var(--shadow);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong { font-size: 0.98rem; }
.brand-text small { color: var(--ink-soft); font-size: 0.72rem; }

.nav { display: flex; gap: 6px; }
.nav a {
  text-decoration: none;
  color: var(--ink-soft);
  font-size: 0.85rem;
  font-weight: 600;
  padding: 8px 10px;
  border-radius: 999px;
}
.nav a.active, .nav a:hover {
  background: #fff;
  color: var(--ink);
  box-shadow: var(--shadow);
}

.main { flex: 1; padding-bottom: 12px; }

.card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 16px;
  margin-bottom: 12px;
}

h1 { font-size: 1.45rem; margin: 0 0 8px; letter-spacing: -0.02em; }
h2 { font-size: 1.1rem; margin: 0 0 8px; }
p { margin: 0 0 10px; }
.muted { color: var(--ink-soft); font-size: 0.92rem; }
.coach {
  background: linear-gradient(135deg, #fff3e0, #e8f8f5);
  border-left: 4px solid var(--accent-2);
  padding: 12px 14px;
  border-radius: 12px;
  font-size: 0.95rem;
  margin: 10px 0 14px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: none;
  cursor: pointer;
  font: inherit;
  font-weight: 700;
  border-radius: 999px;
  padding: 12px 18px;
  text-decoration: none;
  color: #fff;
  background: var(--accent);
  box-shadow: 0 4px 0 #c75a3f;
  transition: transform 0.08s ease;
}
.btn:active { transform: translateY(2px); box-shadow: 0 2px 0 #c75a3f; }
.btn.secondary {
  background: #fff;
  color: var(--ink);
  border: 2px solid var(--line);
  box-shadow: none;
}
.btn.ok { background: var(--ok); box-shadow: 0 4px 0 #1f7a70; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; transform: none; }
.btn-row { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }

.pill {
  display: inline-block;
  background: #fff3e0;
  color: #9a5b1a;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 10px;
  border-radius: 999px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.day-picker {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 8px;
}
.day-chip {
  border: 2px solid var(--line);
  background: #fff;
  border-radius: 12px;
  padding: 10px 12px;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
  min-width: 92px;
  text-align: left;
}
.day-chip small { display: block; color: var(--ink-soft); font-weight: 500; font-size: 0.72rem; }
.day-chip.selected { border-color: var(--accent-2); background: #fff8f0; }
.day-chip.done { border-color: var(--accent-3); }

/* Practice */
.progress-bar {
  height: 8px;
  background: var(--line);
  border-radius: 999px;
  overflow: hidden;
  margin: 8px 0 14px;
}
.progress-bar > span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  border-radius: inherit;
  transition: width 0.25s ease;
}
.q-meta { display: flex; justify-content: space-between; align-items: center; gap: 8px; margin-bottom: 6px; }

.diagram {
  background: #fafafa;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px;
  margin: 12px 0;
  overflow-x: auto;
}
.diagram svg { display: block; max-width: 100%; height: auto; margin: 0 auto; }
.diagram-caption {
  text-align: center;
  font-size: 0.82rem;
  color: var(--ink-soft);
  margin-top: 8px;
}
.diagram table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}
.diagram th, .diagram td {
  border: 1px solid #cfd8dc;
  padding: 8px 10px;
  text-align: center;
}
.diagram th { background: #eceff1; font-weight: 700; }
.diagram caption {
  caption-side: bottom;
  padding-top: 8px;
  color: var(--ink-soft);
  font-size: 0.82rem;
}

.options { display: flex; flex-direction: column; gap: 8px; margin: 12px 0; }
.option {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 12px;
  border: 2px solid var(--line);
  border-radius: 12px;
  background: #fff;
  cursor: pointer;
  text-align: left;
  font: inherit;
}
.option input { margin-top: 3px; accent-color: var(--accent); width: 18px; height: 18px; flex-shrink: 0; }
.option.selected { border-color: var(--accent-2); background: #fff8f0; }
.option.correct { border-color: var(--ok); background: #e8f8f5; }
.option.incorrect { border-color: var(--bad); background: #fdecea; }
.option:disabled { cursor: default; }

.explain {
  margin-top: 10px;
  padding: 12px;
  border-radius: 12px;
  background: #eef7ff;
  border: 1px solid #c5dff5;
  font-size: 0.94rem;
}
.explain.ok { background: #e8f8f5; border-color: #b2dfdb; }
.explain.bad { background: #fdecea; border-color: #f5c6cb; }
.result-banner {
  font-weight: 700;
  margin-bottom: 6px;
}

/* Dashboard */
.stats {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
}
.stat {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 12px;
}
.stat .n { font-size: 1.45rem; font-weight: 800; letter-spacing: -0.02em; }
.stat .l { font-size: 0.75rem; color: var(--ink-soft); font-weight: 600; text-transform: uppercase; }

.bar-list { display: flex; flex-direction: column; gap: 10px; margin-top: 8px; }
.bar-row { display: grid; grid-template-columns: 78px 1fr 48px; gap: 8px; align-items: center; font-size: 0.85rem; }
.bar-track {
  height: 14px;
  background: var(--line);
  border-radius: 999px;
  overflow: hidden;
}
.bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-3), #52b788);
  border-radius: inherit;
  min-width: 0;
}
.gap-list { margin: 0; padding-left: 18px; }
.gap-list li { margin-bottom: 6px; font-size: 0.92rem; }

.empty {
  text-align: center;
  padding: 28px 12px;
  color: var(--ink-soft);
}

.footer {
  text-align: center;
  color: var(--ink-soft);
  font-size: 0.75rem;
  padding: 8px 0 4px;
}

@media (min-width: 480px) {
  .app { padding-left: 18px; padding-right: 18px; }
}

/* Gamification + review */
.stars {
  color: #f4a261;
  letter-spacing: 0.05em;
  font-size: 1.25rem;
  font-weight: 700;
}
.score-banner {
  background: linear-gradient(135deg, #fff3e0, #e8f8f5);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px;
  margin: 10px 0 4px;
  text-align: center;
}
.score-banner.compact { text-align: left; }
.score-stars { margin-bottom: 6px; }
.score-stats {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 4px 8px;
  font-size: 0.92rem;
  margin-bottom: 6px;
}
.score-banner.compact .score-stats { justify-content: flex-start; }
.score-stats .dot { color: var(--ink-soft); }
.celebrate {
  margin: 6px 0 0;
  font-weight: 650;
  font-size: 0.95rem;
}
.mini-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0 0 12px;
  font-size: 0.85rem;
  font-weight: 650;
  color: var(--ink-soft);
}
.mini-stats span {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 10px;
}

.review-stem { font-size: 1rem; font-weight: 650; }
.review-opts { display: flex; flex-direction: column; gap: 6px; margin: 10px 0; }
.review-opt {
  display: grid;
  grid-template-columns: 28px 1fr auto;
  gap: 8px;
  align-items: start;
  padding: 10px 12px;
  border: 2px solid var(--line);
  border-radius: 12px;
  background: #fff;
  font-size: 0.92rem;
}
.review-opt.correct { border-color: var(--ok); background: #e8f8f5; }
.review-opt.incorrect { border-color: var(--bad); background: #fdecea; }
.review-opt.picked:not(.correct):not(.incorrect) { border-color: var(--accent-2); }
.opt-letter {
  font-weight: 800;
  color: var(--ink-soft);
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  background: #f5f5f5;
  border-radius: 8px;
  font-size: 0.8rem;
}
.review-opt.correct .opt-letter { background: #b2dfdb; color: #1b5e20; }
.review-opt.incorrect .opt-letter { background: #ffcdd2; color: #b71c1c; }
.opt-tags { display: flex; flex-direction: column; gap: 4px; align-items: flex-end; }
.tag {
  font-size: 0.65rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  padding: 2px 6px;
  border-radius: 999px;
  white-space: nowrap;
}
.ok-tag { background: #c8e6c9; color: #1b5e20; }
.you-tag { background: #ffe0b2; color: #e65100; }

.why-btn { margin-top: 4px; }
.why-panel {
  margin-top: 10px;
  padding: 12px;
  border-radius: 12px;
  background: #eef7ff;
  border: 1px solid #c5dff5;
  font-size: 0.94rem;
}
.why-panel p { margin-bottom: 8px; }
.why-panel p:last-child { margin-bottom: 0; }
.why-hint { font-size: 0.82rem; }

.bar-meta {
  font-size: 0.78rem;
  margin: -4px 0 8px 78px;
}
.gap-list a { margin-left: 6px; font-weight: 650; color: var(--accent); }

/* Question number pills (1…N) */
.q-pills {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
  margin: 4px 0 10px;
}
.q-pill {
  width: 36px;
  height: 36px;
  border-radius: 999px;
  border: 2px solid #d0d0d0;
  background: #e8e8e8;
  color: var(--ink-soft);
  font: inherit;
  font-weight: 800;
  font-size: 0.9rem;
  cursor: pointer;
  padding: 0;
  transition: background 0.15s ease, border-color 0.15s ease, box-shadow 0.15s ease;
}
.q-pill.unanswered {
  background: #e8e8e8;
  border-color: #d0d0d0;
  color: var(--ink-soft);
}
.q-pill.answered {
  background: linear-gradient(135deg, var(--accent-2), var(--accent));
  border-color: var(--accent);
  color: #fff;
}
.q-pill.current {
  box-shadow: 0 0 0 3px rgba(231, 111, 81, 0.35);
}
.q-pill:active {
  transform: scale(0.96);
}
.practice-nav {
  align-items: center;
}
.practice-nav .btn.ok {
  flex: 1 1 auto;
  min-width: 120px;
}