:root {
  --ink: #171412;
  --muted: #6b6258;
  --line: #efe4d4;
  --bg: #fffaf3;
  --card: #ffffff;
  --orange: #f26b21;
  --orange-d: #d45712;
  --green: #0f9f6e;
  --green-d: #0b7d56;
  --cream: #fff3e6;
  --rose: #e11d48;
  --font-body: "Manrope", system-ui, sans-serif;
  --font-heading: "Space Grotesk", system-ui, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { min-height: 100%; }

/* Accent colour themes */
body.accent-orange { --orange: #f26b21; --orange-d: #d45712; }
body.accent-green { --orange: #0f9f6e; --orange-d: #0b7d56; }
body.accent-amber { --orange: #d97706; --orange-d: #b45309; }
body.accent-rose { --orange: #e11d48; --orange-d: #be123c; }
body {
  font-family: var(--font-body);
  color: var(--ink);
  background:
    radial-gradient(920px 480px at 0% -10%, #ffd7b5 0%, transparent 58%),
    radial-gradient(820px 420px at 100% 0%, #c7f5df 0%, transparent 52%),
    var(--bg);
}
button, input { font-family: inherit; }
a { color: inherit; text-decoration: none; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 20px 72px; }

.nav {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 1120px; margin: 0 auto; padding: 16px 20px;
}
.brand { display: flex; align-items: center; gap: 10px; cursor: pointer; }
.logo {
  width: 36px; height: 36px; border-radius: 50%;
  background: var(--orange); color: #fff; font-weight: 800;
  display: grid; place-items: center; font-size: 12px;
}
.brand b { font-family: var(--font-heading); font-size: 20px; letter-spacing: -0.03em; }
.nav-center { flex: 1; display: flex; justify-content: center; }
.nav-right { display: flex; align-items: center; gap: 8px; }
.icon-btn {
  width: 38px; height: 38px; border-radius: 14px; border: 1px solid var(--line);
  background: rgba(255,255,255,.3); cursor: pointer; backdrop-filter: blur(8px);
}
.top-actions { display: flex; gap: 8px; align-items: center; }

.hero { text-align: center; padding: 40px 0 8px; }
.pill {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 14px; border-radius: 999px;
  background: #fff7ed; border: 1px solid #f3d5b5; color: #9a3412;
  font-size: 13px; font-weight: 650;
}
h1 {
  font-family: var(--font-heading);
  font-size: clamp(32px, 5.2vw, 54px);
  letter-spacing: -0.04em; margin: 16px 0 10px;
}
h1 em { color: var(--orange); font-style: normal; }
.lede { color: var(--muted); font-size: 16px; }

.pair { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; margin: 36px 0 28px; }
.level {
  border: 0; border-radius: 22px; min-height: 214px; padding: 28px;
  color: #fff; text-align: left; cursor: pointer; position: relative; overflow: hidden;
}
.level.primary { background: linear-gradient(145deg, #fb923c, #ea580c); }
.level.secondary { background: linear-gradient(145deg, #34d399, #059669); }
.level::after {
  content: ""; position: absolute; right: -36px; top: -48px;
  width: 180px; height: 180px; border-radius: 50%; background: rgba(255,255,255,.14);
}
.level h2 { font-family: var(--font-heading); font-size: 32px; margin: 16px 0 8px; }
.level p { max-width: 92%; opacity: .95; }
.level .go { margin-top: 22px; font-weight: 750; }

.panel {
  background: rgba(255,255,255,.25); border: 1px solid var(--line);
  border-radius: 24px; padding: 24px 26px;
  box-shadow: 0 12px 30px rgba(160, 100, 40, .06);
  backdrop-filter: blur(14px);
}
.panel.glass-ultra { background: rgba(255,255,255,.02); }
.panel.glass-normal { background: rgba(255,255,255,.16); }
.panel.glass-tinted { background: rgba(242,191,17,.06); }
.panel + .panel { margin-top: 16px; }
.row { display: flex; justify-content: space-between; gap: 12px; align-items: flex-start; }
h2, h3 { font-family: var(--font-heading); }
.chip {
  border-radius: 999px; padding: 4px 10px; font-size: 12px; font-weight: 700;
  background: #ffe4e6; color: #9f1239; white-space: nowrap;
}
.empty { text-align: center; color: var(--muted); padding: 26px 8px; }
.cols { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 16px; }
.box { background: rgba(255,146,60,.08); border-radius: 18px; padding: 16px; min-height: 92px; border: 1px solid rgba(242,107,33,.1); backdrop-filter: blur(10px); }
.tag {
  display: inline-block; margin: 4px 6px 0 0; padding: 4px 10px;
  border-radius: 999px; font-size: 12px; font-weight: 750;
}
.tag.good { background: #d1fae5; color: #065f46; }
.tag.bad { background: #ffe4e6; color: #9f1239; }

.back {
  background: none; border: 0; color: #9a3412; font-weight: 750;
  cursor: pointer; margin: 6px 0 14px;
}
.topic {
  background: rgba(255,255,255,.3); border: 1px solid var(--line); border-radius: 22px;
  padding: 16px 18px; margin-bottom: 12px; backdrop-filter: blur(14px);
}
.topic.glass-ultra { background: rgba(255,255,255,.04); }
.topic.glass-normal { background: rgba(255,255,255,.18); }
.topic.glass-tinted { background: rgba(242,191,17,.08); }
.topic h4 { font-family: var(--font-heading); font-size: 20px; }
.topic p { color: var(--muted); font-size: 14px; margin-top: 4px; }
.actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 12px; }
.btn {
  border: 0; border-radius: 20px; padding: 10px 20px; font-weight: 750; cursor: pointer;
  backdrop-filter: blur(8px);
}
.btn-orange { background: var(--orange); color: #fff; }
.btn-orange:hover { background: var(--orange-d); }
.btn-green { background: var(--green); color: #fff; }
.btn-dark { background: var(--ink); color: #fff; }
.btn-ghost { background: rgba(242,107,33,.1); color: var(--orange); border: 1px solid rgba(242,107,33,.3); }
.btn-outline { background: rgba(255,255,255,.3); border: 1px solid var(--line); }
.btn-rose { background: var(--rose); color: #fff; }

.lesson, .quiz {
  background: var(--card); border: 1px solid var(--line); border-radius: 22px; padding: 24px;
  backdrop-filter: blur(12px);
}
.lesson.glass-ultra, .quiz.glass-ultra { background: rgba(255,255,255,.02); }
.lesson.glass-tinted, .quiz.glass-tinted { background: rgba(242,191,17,.06); }
.kicker {
  font-size: 11px; font-weight: 800; letter-spacing: .1em;
  text-transform: uppercase; color: var(--orange);
}
.lesson h2 { font-size: 30px; margin: 6px 0 12px; }
.block { margin: 16px 0; }
.block h3 { margin-bottom: 6px; }
.step, .ex {
  background: rgba(255,255,255,.25); border-radius: 18px; padding: 14px 18px; margin: 10px 0;
  border: 1px solid rgba(242,191,33,.15); backdrop-filter: blur(10px);
}
.q { font-size: 20px; font-weight: 750; margin: 12px 0 16px; }
.choices { display: grid; gap: 8px; }
.choice {
  text-align: left; padding: 14px 18px; border-radius: 28px;
  border: 1px solid var(--line); background: rgba(255,255,255,.35);
  cursor: pointer; font-weight: 650; backdrop-filter: blur(10px);
  box-shadow: 0 4px 12px rgba(0,0,0,.04);
}
.choice:hover { border-color: var(--orange); transform: translateY(-1px); }
.choice.ok { background: #d1fae5; border-color: #10b981; }
.choice.no { background: #ffe4e6; border-color: #fb7185; }
.choice:disabled { cursor: default; transform: none; }
.choice.glass-ultra { background: rgba(255,255,255,.02); }
.choice.glass-tinted { background: rgba(242,191,17,.06); }
.bar { height: 8px; background: #f3e8d9; border-radius: 99px; overflow: hidden; margin: 10px 0 16px; }
.bar > i { display: block; height: 100%; background: var(--orange); }
.explain { margin-top: 12px; color: var(--muted); }

.graph {
  background: #fff; border: 1px solid var(--line); border-radius: 20px; padding: 18px;
}
.checks { display: grid; gap: 8px; margin: 12px 0; }
@media (min-width: 800px) {
  .graph-grid { display: grid; grid-template-columns: 1fr 240px; gap: 16px; align-items: start; }
}
.checks label {
  display: flex; gap: 10px; align-items: flex-start;
  border: 1px solid var(--line); border-radius: 14px; padding: 10px 12px; cursor: pointer;
}
.checks label.on { background: #fff7ed; border-color: #fdba74; }
canvas {
  width: 100%; height: auto; background: #fffefb;
  border: 1px solid var(--line); border-radius: 12px;
}
.note { color: var(--muted); font-size: 13px; margin-top: 8px; }

.modal {
  position: fixed; inset: 0; background: rgba(23,20,18,.45);
  display: none; align-items: center; justify-content: center; padding: 20px; z-index: 30;
}
.modal.show { display: flex; }
.modal .sheet { background: #fff; border-radius: 18px; padding: 22px; max-width: 440px; width: 100%; }

footer { text-align: center; color: #9ca3af; font-size: 13px; padding: 8px 16px 28px; }

@media (max-width: 760px) {
  .pair, .cols { grid-template-columns: 1fr; }
}

/* Dark mode */
body.dark {
  --ink: #f0ece5;
  --muted: #b9b1a7;
  --line: #3a3631;
  --bg: #12110f;
  --card: #1e1d1b;
  --orange: #fb923c;
  --orange-d: #ea580c;
  --green: #34d399;
  --green-d: #059669;
  --cream: #2d2419;
  --rose: #f87171;
  background:
    radial-gradient(920px 480px at 0% -10%, #3b2a1a 0%, transparent 58%),
    radial-gradient(820px 420px at 100% 0%, #1a3a33 0%, transparent 52%),
    var(--bg);
}
body.dark .btn-ghost { background: #2d2419; border-color: #4a443e; color: #fb923c; }
body.dark canvas { background: #12110f; }
body.dark .modal { background: rgba(18,17,15,.7); }