:root {
  --bg: #f6f7fb; --card: #ffffff; --text: #1b1f2a; --muted: #687087; --line: #e2e5ee;
  --accent: #2f5bd3; --accent-text: #ffffff; --good: #1f8a4c; --good-bg: #e3f5ea; --bad: #c0392b; --bad-bg: #fbe7e4;
  --s-new: #c9cfdc; --s-learning: #e9a23b; --s-known: #4f8fe8; --s-mastered: #1f8a4c;
  --radius: 14px; --shadow: 0 1px 3px rgba(20, 30, 60, .08);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #12151c; --card: #1c212c; --text: #e8ebf2; --muted: #9aa2b6; --line: #2c3341;
    --accent: #6b8ff0; --accent-text: #0d1220; --good: #4cc27f; --good-bg: #173326; --bad: #f07b6b; --bad-bg: #3a1e1b;
    --s-new: #3a4253; --shadow: none;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--bg); color: var(--text); font: 16px/1.5 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; }
button, select, input { font: inherit; color: inherit; }
a { color: var(--accent); }
[hidden] { display: none !important; }
.sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.muted { color: var(--muted); }
.center { text-align: center; }
.small { font-size: 14px; }

.top { position: sticky; top: 0; z-index: 5; display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  padding: 10px 16px; background: var(--card); border-bottom: 1px solid var(--line); }
.brand { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 18px; margin-right: auto; }
.brand img { border-radius: 7px; }
nav { display: flex; gap: 4px; order: 3; width: 100%; overflow-x: auto; }
@media (min-width: 720px) { nav { order: 0; width: auto; } }
.tab { border: 0; background: none; padding: 8px 12px; border-radius: 10px; cursor: pointer; color: var(--muted); white-space: nowrap; }
.tab.active { background: var(--bg); color: var(--text); font-weight: 600; }
.lang { display: flex; align-items: center; gap: 8px; }
.flag { display: block; border-radius: 3px; box-shadow: 0 0 0 1px rgba(0,0,0,.15); flex: none; }
.lang select { padding: 6px 8px; border-radius: 10px; border: 1px solid var(--line); background: var(--card); }

main { max-width: 760px; margin: 0 auto; padding: 18px 16px 40px; }
.foot { text-align: center; color: var(--muted); font-size: 14px; padding: 0 16px 28px; }

.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 18px; margin-bottom: 14px; }
.card h2 { margin: 0 0 6px; font-size: 19px; }
.card h3 { margin: 0 0 8px; font-size: 16px; }
.row { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; }
.spread { justify-content: space-between; }
.grid2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 10px; }

.btn { border: 1px solid var(--line); background: var(--card); padding: 10px 16px; border-radius: 12px; cursor: pointer; }
.btn:hover { border-color: var(--accent); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-text); font-weight: 600; }
.btn.danger { color: var(--bad); }
.btn:disabled { opacity: .5; cursor: default; }
.btn.big { width: 100%; padding: 14px; font-size: 17px; }
.icon-btn { border: 1px solid var(--line); background: var(--card); width: 40px; height: 40px; border-radius: 50%; cursor: pointer;
  display: inline-grid; place-items: center; font-size: 18px; flex: none; }
.icon-btn:hover { border-color: var(--accent); }

.hero { text-align: center; padding: 36px 18px; }
.hero h1 { font-size: 28px; margin: 0 0 8px; }
.hero ul { text-align: left; max-width: 460px; margin: 18px auto; padding-left: 20px; }

.stat { background: var(--bg); border-radius: 12px; padding: 12px; }
.stat b { display: block; font-size: 26px; line-height: 1.2; }
.stat span { color: var(--muted); font-size: 14px; }

.bar { display: flex; height: 14px; border-radius: 7px; overflow: hidden; background: var(--s-new); }
.bar i { display: block; height: 100%; }
.legend { display: flex; flex-wrap: wrap; gap: 6px 14px; font-size: 14px; color: var(--muted); margin-top: 8px; }
.dot { display: inline-block; width: 10px; height: 10px; border-radius: 50%; margin-right: 5px; vertical-align: middle; }
.s-new { background: var(--s-new); } .s-learning { background: var(--s-learning); }
.s-known { background: var(--s-known); } .s-mastered { background: var(--s-mastered); }

.chart { display: flex; align-items: flex-end; gap: 3px; height: 110px; padding-top: 6px; }
.chart div { flex: 1; background: var(--accent); border-radius: 3px 3px 0 0; min-height: 2px; opacity: .85; }
.chart div.zero { background: var(--line); }
.chart-labels { display: flex; justify-content: space-between; font-size: 12px; color: var(--muted); }

/* Learning card */
.word-big { font-size: 40px; font-weight: 700; line-height: 1.1; word-break: break-word; }
.ipa { color: var(--muted); font-size: 18px; }
.pos { display: inline-block; font-size: 13px; color: var(--muted); border: 1px solid var(--line); border-radius: 8px; padding: 1px 8px; }
.translation { font-size: 22px; margin: 10px 0; }
.example { border-left: 3px solid var(--accent); padding: 4px 0 4px 12px; margin: 14px 0 4px; }
.example .ru { color: var(--muted); }
.progress-line { height: 6px; background: var(--line); border-radius: 3px; overflow: hidden; margin-bottom: 14px; }
.progress-line i { display: block; height: 100%; background: var(--accent); transition: width .2s; }

/* Quiz */
.prompt { text-align: center; padding: 10px 0 16px; }
.prompt .q { font-size: 34px; font-weight: 700; word-break: break-word; }
.prompt .hint { color: var(--muted); font-size: 15px; margin-bottom: 6px; }
.options { display: grid; gap: 10px; }
@media (min-width: 560px) { .options { grid-template-columns: 1fr 1fr; } }
.option { text-align: left; padding: 14px; border-radius: 12px; border: 1px solid var(--line); background: var(--card); cursor: pointer; font-size: 17px; }
.option:hover:not(:disabled) { border-color: var(--accent); }
.option.right { background: var(--good-bg); border-color: var(--good); }
.option.wrong { background: var(--bad-bg); border-color: var(--bad); }
.type-input { width: 100%; padding: 14px; font-size: 20px; border-radius: 12px; border: 1px solid var(--line); background: var(--card); text-align: center; }
.feedback { margin-top: 14px; padding: 12px 14px; border-radius: 12px; }
.feedback.good { background: var(--good-bg); color: var(--good); }
.feedback.bad { background: var(--bad-bg); color: var(--bad); }
.feedback .detail { color: var(--text); margin-top: 4px; }

/* Words list */
.filters { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 12px; }
.filters input { flex: 1 1 200px; padding: 10px 12px; border-radius: 12px; border: 1px solid var(--line); background: var(--card); }
.chip { border: 1px solid var(--line); background: var(--card); padding: 6px 12px; border-radius: 20px; cursor: pointer; font-size: 14px; }
.chip.active { background: var(--accent); color: var(--accent-text); border-color: var(--accent); }
.wlist { list-style: none; margin: 0; padding: 0; }
.wlist li { display: grid; grid-template-columns: 40px 1fr auto; gap: 10px; align-items: center; padding: 10px 4px; border-bottom: 1px solid var(--line); }
.wlist .rank { color: var(--muted); font-size: 13px; text-align: right; }
.wlist .en { font-weight: 600; }
.wlist .ru { color: var(--muted); font-size: 14px; }
.wlist .meta { text-align: right; font-size: 13px; color: var(--muted); }
.status { display: inline-block; font-size: 12px; padding: 1px 8px; border-radius: 8px; color: #fff; }
.status.new { background: var(--s-new); color: var(--text); }
.status.learning { background: var(--s-learning); } .status.known { background: var(--s-known); } .status.mastered { background: var(--s-mastered); }

.setting { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 10px 0; border-bottom: 1px solid var(--line); flex-wrap: wrap; }
.setting:last-child { border-bottom: 0; }
.setting select { padding: 8px 10px; border-radius: 10px; border: 1px solid var(--line); background: var(--card); }

.modal { position: fixed; inset: 0; background: rgba(10, 14, 25, .55); display: grid; place-items: center; padding: 16px; z-index: 20; }
.modal-box { background: var(--card); border-radius: var(--radius); padding: 22px; max-width: 420px; width: 100%; }
.modal-box h2 { margin: 0 0 8px; }
.toast { position: fixed; bottom: 16px; left: 50%; transform: translateX(-50%); background: var(--text); color: var(--bg); padding: 10px 16px; border-radius: 10px; z-index: 30; font-size: 14px; }
@media (max-width: 480px) {
  nav { scrollbar-width: none; justify-content: space-between; }
  nav::-webkit-scrollbar { display: none; }
  .tab { padding: 8px 6px; font-size: 15px; }
}