:root {
  --bg: #f5f2ea;
  --surface: #fffdf8;
  --ink: #1e2430;
  --muted: #6b7180;
  --line: #e2ddd0;
  --accent: #0f6e66;
  --accent-ink: #ffffff;
  --accent-soft: #dcefe9;
  --bad: #b4452f;
  --bad-soft: #f6e1da;
  --mark: #fff0b8;
  --shadow: 0 1px 2px rgba(30, 36, 48, .06), 0 8px 24px rgba(30, 36, 48, .07);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171d;
    --surface: #1c2029;
    --ink: #e9e6de;
    --muted: #9aa0ad;
    --line: #2c323e;
    --accent: #4fc2b3;
    --accent-ink: #0c1f1c;
    --accent-soft: #1d3a37;
    --bad: #f08a72;
    --bad-soft: #40241d;
    --mark: #5a4a10;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px rgba(0, 0, 0, .25);
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  padding-bottom: env(safe-area-inset-bottom);
}
button, input, textarea, select { font: inherit; color: inherit; }
button { cursor: pointer; }

.top {
  position: sticky; top: 0; z-index: 5;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
  padding: 12px 16px 0;
}
.brand { font-weight: 800; font-size: 20px; letter-spacing: -.02em; max-width: 760px; margin: 0 auto 10px; }
.brand span { color: var(--accent); }
.tabs { display: flex; gap: 4px; max-width: 760px; margin: 0 auto; overflow-x: auto; scrollbar-width: none; }
.tabs::-webkit-scrollbar { display: none; }
.tabs button {
  background: none; border: 0; border-bottom: 3px solid transparent;
  padding: 8px 12px 10px; color: var(--muted); font-weight: 600; white-space: nowrap;
}
.tabs button.on { color: var(--ink); border-bottom-color: var(--accent); }

main { max-width: 760px; margin: 0 auto; padding: 20px 16px 64px; }
h1 { font-size: 24px; letter-spacing: -.02em; margin: 0 0 4px; }
h2 { font-size: 17px; margin: 28px 0 10px; }
p.lead { color: var(--muted); margin: 0 0 18px; }
.muted { color: var(--muted); }
.small { font-size: 14px; }

.btn {
  border: 1px solid var(--line); background: var(--surface); border-radius: 10px;
  padding: 10px 16px; font-weight: 600;
}
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.btn.danger { color: var(--bad); }
.btn:disabled { opacity: .5; cursor: default; }
.btn.block { width: 100%; padding: 14px 16px; }
.row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }

.chips { display: flex; gap: 6px; flex-wrap: wrap; margin: 0 0 14px; }
.chip {
  border: 1px solid var(--line); background: var(--surface); color: var(--muted);
  border-radius: 999px; padding: 6px 12px; font-size: 14px; font-weight: 600;
}
.chip.on { background: var(--accent-soft); border-color: var(--accent); color: var(--ink); }
.chip b { font-weight: 600; opacity: .6; margin-left: 4px; }

.stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; margin: 0 0 18px; }
.stat { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 12px; }
.stat strong { display: block; font-size: 24px; line-height: 1.1; font-variant-numeric: tabular-nums; }
.stat span { font-size: 13px; color: var(--muted); }

.seg { display: inline-flex; border: 1px solid var(--line); border-radius: 10px; overflow: hidden; background: var(--surface); }
.seg button { border: 0; background: none; padding: 8px 12px; font-size: 14px; font-weight: 600; color: var(--muted); }
.seg button.on { background: var(--accent-soft); color: var(--ink); }
.opts { display: flex; gap: 10px; flex-wrap: wrap; margin: 0 0 18px; }

/* Flashcard */
.progress { height: 6px; background: var(--line); border-radius: 3px; overflow: hidden; margin: 6px 0 14px; }
.progress i { display: block; height: 100%; background: var(--accent); transition: width .2s; }
.session-head { display: flex; justify-content: space-between; align-items: center; font-size: 14px; color: var(--muted); }
.linkbtn { background: none; border: 0; padding: 4px 0; color: var(--muted); text-decoration: underline; font-size: 14px; }
.card {
  background: var(--surface); border: 1px solid var(--line); border-radius: 18px; box-shadow: var(--shadow);
  min-height: 320px; padding: 28px 22px; display: flex; flex-direction: column; justify-content: center;
  text-align: center; cursor: pointer; user-select: none; -webkit-tap-highlight-color: transparent;
}
.card .type { font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--accent); font-weight: 700; }
.card .word { font-size: clamp(28px, 8vw, 40px); font-weight: 800; letter-spacing: -.02em; margin: 8px 0; overflow-wrap: anywhere; }
.card .hint { color: var(--muted); font-size: 14px; margin-top: 18px; }
.card .tr { font-size: 22px; font-weight: 700; margin: 4px 0 6px; }
.card .en { color: var(--muted); margin: 0 0 16px; }
.card .ex { border-top: 1px solid var(--line); padding-top: 14px; margin-top: 4px; text-align: left; }
.card .ex + .ex { margin-top: 12px; }
.card .ex p { margin: 0 0 4px; }
.card .ex .t { color: var(--muted); font-size: 15px; }
.card .ex .lbl { font-size: 11px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); font-weight: 700; margin-bottom: 4px; }
mark { background: var(--mark); color: inherit; border-radius: 3px; padding: 0 2px; }
.speak {
  border: 1px solid var(--line); background: var(--bg); border-radius: 999px;
  width: 36px; height: 36px; padding: 0; display: inline-grid; place-items: center; font-size: 16px; line-height: 1;
}
.grade { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 14px; }
.grade .btn { padding: 16px; font-size: 17px; }
.grade .no { background: var(--bad-soft); border-color: transparent; color: var(--bad); }
.grade .yes { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.keys { text-align: center; font-size: 13px; color: var(--muted); margin-top: 10px; }
@media (hover: none) { .keys { display: none; } }

.empty { background: var(--surface); border: 1px dashed var(--line); border-radius: 14px; padding: 28px 20px; text-align: center; }
.empty .big { font-size: 20px; font-weight: 700; margin-bottom: 6px; }

/* Word list */
.field, textarea {
  width: 100%; border: 1px solid var(--line); background: var(--surface); border-radius: 10px; padding: 11px 12px;
}
.field:focus, textarea:focus { outline: 2px solid var(--accent); outline-offset: -1px; }
textarea { min-height: 200px; resize: vertical; line-height: 1.5; }
.words { list-style: none; padding: 0; margin: 0; border: 1px solid var(--line); border-radius: 14px; background: var(--surface); overflow: hidden; }
.words li { border-top: 1px solid var(--line); }
.words li:first-child { border-top: 0; }
.wrow { display: flex; align-items: center; gap: 10px; padding: 11px 12px; cursor: pointer; }
.wrow .main { flex: 1; min-width: 0; }
.wrow .w { font-weight: 700; }
.wrow .tag { font-size: 12px; color: var(--accent); font-weight: 600; margin-left: 6px; }
.wrow .m { color: var(--muted); font-size: 14.5px; overflow-wrap: anywhere; }
.star { border: 0; background: none; font-size: 20px; padding: 4px 6px; color: var(--line); line-height: 1; }
.star.on { color: #e0a100; }
.detail { padding: 0 12px 14px 12px; font-size: 15px; }
.detail p { margin: 0 0 6px; }
.detail .acts { margin-top: 10px; }
.box { font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; }

/* Extract */
.pick { display: flex; gap: 10px; align-items: flex-start; padding: 10px 12px; }
.pick input { width: 20px; height: 20px; margin: 2px 0 0; accent-color: var(--accent); flex: none; }
.pick .main { flex: 1; min-width: 0; }
.pick .ctx { font-size: 13.5px; color: var(--muted); margin-top: 2px; overflow-wrap: anywhere; }
.pick .skip { border: 0; background: none; color: var(--muted); font-size: 13px; text-decoration: underline; padding: 2px 0; white-space: nowrap; }
.grouphead { display: flex; justify-content: space-between; align-items: baseline; gap: 10px; margin: 26px 0 8px; }
.grouphead h2 { margin: 0; }
.sticky-bar {
  position: sticky; bottom: 0; background: var(--bg); padding: 12px 0 calc(12px + env(safe-area-inset-bottom));
  margin-top: 16px; border-top: 1px solid var(--line);
}

/* Form */
form.cardform { display: grid; gap: 10px; }
form.cardform label { font-size: 13px; font-weight: 600; color: var(--muted); display: grid; gap: 4px; }
form.cardform textarea { min-height: 70px; }
.note { background: var(--accent-soft); border-radius: 10px; padding: 10px 12px; font-size: 14px; }

#toast {
  position: fixed; left: 50%; bottom: 24px; transform: translate(-50%, 20px); opacity: 0; pointer-events: none;
  background: var(--ink); color: var(--bg); padding: 10px 16px; border-radius: 999px; font-size: 14px; font-weight: 600;
  transition: opacity .2s, transform .2s; max-width: calc(100vw - 32px); text-align: center; z-index: 10;
}
#toast.show { opacity: 1; transform: translate(-50%, 0); }

@media (max-width: 420px) {
  .tabs { gap: 0; justify-content: space-between; }
  .tabs button { font-size: 13.5px; padding: 8px 3px 10px; }
  .stat strong { font-size: 20px; }
  .card { min-height: 300px; padding: 22px 16px; }
}