:root {
  --red: #ba0c2f;
  --navy: #00205b;
  --bg: #f4f5f8;
  --card: #ffffff;
  --text: #15192b;
  --muted: #6b7185;
  --line: #e3e5ec;
  --good: #1f8a4c;
  --good-bg: #e6f6ec;
  --bad: #c62828;
  --bad-bg: #fdecec;
  --tip: #eef3ff;
  --warn: #fff6e0;
  --radius: 16px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1220;
    --card: #1a1e30;
    --text: #eef0f7;
    --muted: #9aa0b5;
    --line: #2b3047;
    --good-bg: #143823;
    --bad-bg: #3d1717;
    --tip: #1d2747;
    --warn: #3a3018;
    --navy: #8fb0ff;
  }
}
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }
[hidden] { display: none !important; }
html, body { margin: 0; }
body {
  font: 17px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  padding-bottom: calc(72px + env(safe-area-inset-bottom));
}
button { font: inherit; color: inherit; cursor: pointer; }
input, textarea, select { font: inherit; }

/* Header & tabs */
#top {
  position: sticky; top: 0; z-index: 5;
  display: flex; align-items: center; gap: 8px;
  padding: calc(10px + env(safe-area-inset-top)) 16px 10px;
  background: var(--red); color: #fff;
}
#top h1 { font-size: 19px; margin: 0; flex: 1; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
#back { background: none; border: 0; color: #fff; font-size: 32px; line-height: 1; padding: 0 8px 4px 0; }
#tabs {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 5;
  display: flex; background: var(--card); border-top: 1px solid var(--line);
  padding-bottom: env(safe-area-inset-bottom);
}
#tabs button { flex: 1; background: none; border: 0; padding: 8px 0 6px; font-size: 11px; color: var(--muted); display: flex; flex-direction: column; align-items: center; }
#tabs button span { font-size: 22px; line-height: 1.2; }
#tabs button.on { color: var(--red); font-weight: 600; }

main { max-width: 640px; margin: 0 auto; padding: 16px; }
h2 { font-size: 18px; margin: 24px 0 10px; }
h3 { font-size: 16px; margin: 20px 0 8px; }
.muted { color: var(--muted); }
.center { text-align: center; }
small { font-size: 13px; }

/* Buttons */
.big {
  display: flex; flex-direction: column; align-items: flex-start; width: 100%;
  margin: 10px 0; padding: 14px 16px; border-radius: var(--radius);
  border: 1px solid var(--line); background: var(--card); text-align: left; font-weight: 600;
}
.big small { font-weight: 400; color: var(--muted); margin-top: 2px; }
.big.primary { background: var(--red); border-color: var(--red); color: #fff; align-items: center; text-align: center; }
.big.primary small { color: #ffe3e8; }
.big:disabled { opacity: .5; }

/* Home */
.hero { background: linear-gradient(135deg, var(--navy), #1b3b8f); color: #fff; border-radius: var(--radius); padding: 18px; }
@media (prefers-color-scheme: dark) { .hero { background: linear-gradient(135deg, #12235a, #23409a); } }
.hero p { margin: 4px 0 0; }
.streak { display: flex; align-items: baseline; gap: 8px; }
.streak b { font-size: 40px; line-height: 1; }
.hello { font-size: 15px; opacity: .9; }
.prog { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 12px 14px; margin-bottom: 10px; }
.row { display: flex; justify-content: space-between; align-items: baseline; }
.bar { margin-top: 8px; font-size: 13px; color: var(--muted); }
.bar i { display: block; height: 8px; background: var(--line); border-radius: 4px; overflow: hidden; margin-top: 3px; }
.bar em { display: block; height: 100%; background: var(--red); border-radius: 4px; }

/* Lists */
.list { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.item { display: flex; align-items: center; gap: 12px; width: 100%; padding: 12px 14px; border: 0; border-bottom: 1px solid var(--line); background: none; text-align: left; }
.item:last-child { border-bottom: 0; }
.grow { flex: 1; min-width: 0; }
.num { width: 28px; height: 28px; border-radius: 50%; background: var(--line); display: grid; place-items: center; font-size: 13px; font-weight: 600; flex: none; }
.num.ok { background: var(--good); color: #fff; }
.dot { width: 10px; height: 10px; border-radius: 50%; background: var(--line); flex: none; }
.dot.l { background: #f0a500; }
.dot.m { background: var(--good); }

/* Lesson */
.lesson { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 16px; }
.lesson h2 { margin-top: 6px; }
.lesson p { margin: 10px 0; }
.badge { display: inline-block; background: var(--red); color: #fff; font-size: 12px; font-weight: 700; border-radius: 6px; padding: 2px 8px; }
.no { color: var(--navy); cursor: pointer; }
b.no { font-weight: 650; }
.ex { border-left: 4px solid var(--red); padding: 4px 0 4px 12px; margin: 12px 0; }
.ex div { margin: 6px 0; }
.ex b { display: block; }
.ex i { display: block; color: var(--muted); font-size: 15px; }
.tip { border-radius: 12px; padding: 10px 12px; margin: 12px 0; font-size: 15px; background: var(--tip); }
.tip.key::before { content: "💡 "; }
.tip.warn { background: var(--warn); }
.tip.warn::before { content: "⚠️ "; }
.tip.ph::before { content: "🇵🇭 "; }
.table-wrap { overflow-x: auto; }
table.g { width: 100%; border-collapse: collapse; margin: 12px 0; font-size: 15px; }
table.g th, table.g td { border-bottom: 1px solid var(--line); padding: 7px 6px; text-align: left; vertical-align: top; }
table.g th { font-size: 13px; color: var(--muted); font-weight: 600; }
table.g th:empty { padding: 0; }

/* Quiz */
.qprog { height: 6px; background: var(--line); border-radius: 3px; overflow: hidden; }
.qprog i { display: block; height: 100%; background: var(--red); transition: width .3s; }
.q { font-size: 20px; line-height: 1.4; margin: 6px 0 16px; }
.opts { display: grid; gap: 10px; }
.opt { padding: 14px 16px; border-radius: 14px; border: 2px solid var(--line); background: var(--card); text-align: left; font-size: 17px; }
.opt.right { border-color: var(--good); background: var(--good-bg); }
.opt.wrong { border-color: var(--bad); background: var(--bad-bg); }
.quiz input[type=text] { width: 100%; padding: 14px; font-size: 18px; border-radius: 14px; border: 2px solid var(--line); background: var(--card); color: var(--text); }
.keys { display: flex; gap: 8px; margin: 10px 0; }
.keys button { flex: 1; padding: 10px; border-radius: 12px; border: 1px solid var(--line); background: var(--card); font-size: 20px; }
.fb { margin: 14px 0 0; border-radius: 14px; }
.fb.good, .fb.bad { padding: 12px 14px; }
.fb.good { background: var(--good-bg); }
.fb.bad { background: var(--bad-bg); }
.fb p { margin: 6px 0 0; font-size: 15px; }
.result { text-align: center; padding: 24px 0 8px; }
.score { font-size: 56px; font-weight: 800; color: var(--red); }

/* Flashcards */
.chips { display: flex; gap: 8px; margin-bottom: 12px; }
.chip { flex: 1; padding: 10px 0; border-radius: 12px; border: 1px solid var(--line); background: var(--card); font-weight: 700; }
.chip.on { background: var(--red); border-color: var(--red); color: #fff; }
.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; }
.stat { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 10px; text-align: center; }
.stat b { display: block; font-size: 24px; }
.stat span { font-size: 12px; color: var(--muted); }
.seg { display: flex; background: var(--line); border-radius: 12px; padding: 3px; margin: 12px 0; }
.seg button { flex: 1; border: 0; background: none; border-radius: 10px; padding: 8px 4px; font-size: 14px; }
.seg button.on { background: var(--card); font-weight: 700; box-shadow: 0 1px 3px rgba(0,0,0,.15); }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 20px; padding: 16px; min-height: 260px; display: flex; flex-direction: column; }
.meta { display: flex; justify-content: space-between; gap: 8px; font-size: 12px; color: var(--muted); }
.meta .new { color: var(--red); font-weight: 700; }
.front, .back { text-align: center; }
.front { flex: 1; display: flex; flex-direction: column; justify-content: center; padding: 24px 0 12px; }
.word { font-size: 30px; font-weight: 700; line-height: 1.25; }
.mean { font-size: 22px; font-weight: 600; }
.back { border-top: 1px dashed var(--line); padding-top: 14px; }
.exs { margin-top: 12px; font-size: 16px; }
.exs i { display: block; color: var(--muted); font-size: 14px; }
.hint { font-size: 13px; color: var(--muted); margin-top: 8px; }
.rate { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; margin-top: 12px; }
.rate button { border: 0; border-radius: 14px; padding: 12px 4px; font-weight: 700; color: #fff; display: flex; flex-direction: column; align-items: center; }
.rate button small { font-weight: 400; opacity: .9; font-size: 12px; }
.r0 { background: #c62828; } .r1 { background: #e07b00; } .r2 { background: #1f8a4c; } .r3 { background: #1565c0; }
.word-row b { font-weight: 600; }

/* Settings */
.set { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 14px; border-bottom: 1px solid var(--line); }
.set:last-child { border-bottom: 0; }
.set select { padding: 6px 8px; border-radius: 10px; border: 1px solid var(--line); background: var(--bg); color: var(--text); }
textarea { width: 100%; min-height: 90px; border-radius: 12px; border: 1px solid var(--line); background: var(--card); color: var(--text); padding: 10px; font-size: 13px; }
.box { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px; }
.box ol { margin: 6px 0 0; padding-left: 20px; }