:root {
  --bg: #f7f7f5; --card: #ffffff; --ink: #1d1d1f; --muted: #6b6b70; --line: #e4e4e0;
  --accent: #2563eb; --accent-soft: #e6eefe; --good: #15803d; --good-soft: #e3f4e8;
  --warn: #b45309; --warn-soft: #fdf1df; --bad: #b91c1c; --bad-soft: #fde8e8; --ref: #9ca3af;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121214; --card: #1c1c1f; --ink: #ececee; --muted: #9a9aa2; --line: #2e2e33;
    --accent: #6ea0ff; --accent-soft: #1e2a44; --good: #4ade80; --good-soft: #15291c;
    --warn: #fbbf24; --warn-soft: #2e2512; --bad: #f87171; --bad-soft: #321818; --ref: #6b7280;
  }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; }
a { color: var(--accent); }
.top { position: sticky; top: 0; z-index: 5; display: flex; align-items: center; gap: 16px; flex-wrap: wrap;
  padding: calc(10px + env(safe-area-inset-top)) max(16px, env(safe-area-inset-right)) 10px max(16px, env(safe-area-inset-left)); background: var(--card); border-bottom: 1px solid var(--line); }
.brand { font-weight: 700; text-decoration: none; color: var(--ink); }
nav { display: flex; gap: 4px; flex-wrap: wrap; flex: 1; }
nav a { padding: 6px 10px; border-radius: 8px; text-decoration: none; color: var(--muted); font-size: 15px; }
nav a.on { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
main { max-width: 860px; margin: 0 auto; padding: 16px; }
.foot { text-align: center; color: var(--muted); font-size: 13px; padding: 24px 16px; }
h1 { font-size: 26px; margin: 8px 0 4px; } h2 { font-size: 20px; margin: 0 0 8px; } h3 { font-size: 16px; margin: 12px 0 6px; }
.muted { color: var(--muted); } .small { font-size: 13px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 16px; margin: 12px 0; }
.row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.grow { flex: 1; }
button, select, input[type=text], input[type=search], input[type=number] {
  font: inherit; font-size: 15px; border-radius: 10px; border: 1px solid var(--line); background: var(--card); color: var(--ink); padding: 7px 12px; }
button { cursor: pointer; }
button:hover { border-color: var(--accent); }
button.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
button.rec { background: var(--bad); color: #fff; border-color: var(--bad); }
button.rec.live { animation: pulse 1s infinite; }
button:disabled { opacity: .45; cursor: default; }
@keyframes pulse { 50% { opacity: .6; } }
.pill { font-size: 12px; padding: 3px 9px; border-radius: 99px; background: var(--line); color: var(--muted); white-space: nowrap; }
.pill.on { background: var(--good-soft); color: var(--good); }
.tag { display: inline-block; font-size: 12px; padding: 1px 8px; border-radius: 99px; background: var(--accent-soft); color: var(--accent); margin-right: 4px; }
.tag.hi { background: var(--warn-soft); color: var(--warn); }

/* annotated sentences */
.say { font-size: 22px; line-height: 1.9; }
.say .w { cursor: pointer; border-radius: 4px; padding: 0 1px; }
.say .w:hover { background: var(--accent-soft); }
.say .cw { font-weight: 600; }
.say .fn { color: var(--muted); font-size: .82em; font-weight: 400; }
.say .focus { color: var(--accent); font-weight: 800; font-size: 1.12em; }
.say .flap { text-decoration: underline dotted var(--warn) 2px; text-underline-offset: 5px; }
.say .pause { color: var(--accent); opacity: .55; font-weight: 300; margin: 0 1px; }
.say .link { color: var(--warn); font-weight: 700; margin: 0 -2px; }
.say .w.ok { background: var(--good-soft); } .say .w.mid { background: var(--warn-soft); } .say .w.bad { background: var(--bad-soft); }
.ipa { font-family: "Charis SIL", "Doulos SIL", "Lucida Grande", serif; color: var(--muted); font-size: 15px; }
.legend { font-size: 12px; color: var(--muted); }
.legend b { color: var(--accent); }

/* results */
.result { margin-top: 12px; border-top: 1px dashed var(--line); padding-top: 12px; }
.score { font-size: 28px; font-weight: 800; }
.score.good { color: var(--good); } .score.mid { color: var(--warn); } .score.bad { color: var(--bad); }
.metrics { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 8px; margin: 8px 0; }
.metric { background: var(--bg); border-radius: 10px; padding: 8px 10px; }
.metric b { display: block; font-size: 18px; }
.metric span { font-size: 12px; color: var(--muted); }
.tip { background: var(--warn-soft); border-radius: 10px; padding: 8px 12px; margin: 6px 0; font-size: 15px; }
.tip code { font-family: inherit; font-weight: 700; }
canvas.contour { width: 100%; height: 150px; background: var(--bg); border-radius: 10px; display: block; margin: 8px 0; }
.phones { font-family: "Charis SIL", serif; font-size: 15px; }
.phones .ph { display: inline-block; padding: 0 3px; margin: 1px; border-radius: 4px; }
.phones .ph.bad { background: var(--bad-soft); color: var(--bad); }

/* blocks / checklist */
.block { padding: 0; overflow: visible; }
.bhead { display: flex; align-items: center; gap: 10px; padding: 14px 16px; cursor: pointer; border-radius: 14px; }
.block.open .bhead { position: sticky; top: var(--header-h, 64px); z-index: 3; background: var(--card); border-bottom: 1px solid var(--line); border-radius: 14px 14px 0 0; }
.bhead .t { font-weight: 700; flex: 1; }
.chev { color: var(--muted); transition: transform .2s; }
.block.open .chev { transform: rotate(180deg); }
.checkwrap { display: flex; padding: 6px; margin: -6px; }
.block .body, .block .bfoot { display: none; padding: 0 16px; }
.block.open .body { display: block; padding-top: 10px; }
.block.open .bfoot { display: flex; justify-content: flex-end; padding: 10px 16px 16px; }
.block.is-done .t { color: var(--good); }
.check { width: 22px; height: 22px; accent-color: var(--good); }
.timer { font-variant-numeric: tabular-nums; color: var(--muted); font-size: 14px; }

/* vocab */
.vocab-head { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.vocab-head .word { font-size: 22px; font-weight: 700; }
.def { margin: 4px 0; }
.ex { font-style: italic; color: var(--muted); }
.vlist .card { padding: 12px 14px; margin: 8px 0; }

/* quiz */
.quiz button.choice { min-width: 110px; font-size: 18px; }
.quiz .right { background: var(--good-soft); border-color: var(--good); }
.quiz .wrong { background: var(--bad-soft); border-color: var(--bad); }

/* conversations */
.chat { display: flex; flex-direction: column; gap: 10px; margin-top: 12px; }
.bubble { border-radius: 16px; padding: 10px 14px; max-width: 92%; }
.bubble.them { align-self: flex-start; background: var(--bg); font-size: 18px; }
.bubble.you { align-self: flex-end; background: var(--accent-soft); width: 92%; }
.bubble.you .say { font-size: 19px; }
.bubble.now { outline: 2px solid var(--accent); }

/* stories & game */
.reader-bar { position: sticky; top: var(--header-h, 64px); z-index: 4; background: var(--bg); padding: 8px 0; }
.say.story { font-size: 20px; line-height: 2; }
.sent { cursor: pointer; border-radius: 6px; transition: background .2s; }
.sent:hover { background: var(--bg); }
.sent.reading { background: var(--accent-soft); }
.sent.yourturn { background: var(--warn-soft); }
.game-words { display: flex; flex-wrap: wrap; gap: 8px; }
.gw { font-size: 19px; padding: 8px 12px; }
.gw.right { background: var(--good-soft); border-color: var(--good); color: var(--good); font-weight: 700; }
.gw.wrong { background: var(--bad-soft); border-color: var(--bad); }

/* progress */
.hrow { border-bottom: 1px solid var(--line); padding: 8px 0; }
.hsum { cursor: pointer; }
.hdet .card-inner { margin-top: 6px; }
.grid30 { display: grid; grid-template-columns: repeat(10, 1fr); gap: 6px; }
.grid30 a { aspect-ratio: 1; display: flex; align-items: center; justify-content: center; border-radius: 8px;
  background: var(--bg); border: 1px solid var(--line); text-decoration: none; color: var(--muted); font-size: 14px; }
.grid30 a.done { background: var(--good-soft); color: var(--good); border-color: var(--good); font-weight: 700; }
.grid30 a.today { outline: 2px solid var(--accent); }
.grid30 a.base::after { content: "★"; font-size: 9px; margin-left: 1px; }
svg.chart { width: 100%; height: 160px; }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
td, th { padding: 6px; border-bottom: 1px solid var(--line); text-align: left; }
.banner { background: var(--accent-soft); border-radius: 12px; padding: 10px 14px; margin: 10px 0; font-size: 14px; }
.banner.warn { background: var(--warn-soft); }
@media (max-width: 600px) {
  .say { font-size: 19px; }
  .top { gap: 6px 8px; padding-bottom: 6px; }
  .brand { flex: 1; font-size: 15px; }
  nav { order: 3; flex: 0 0 100%; flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none; margin: 0 -16px; padding: 0 12px; }
  nav::-webkit-scrollbar { display: none; }
  nav a { padding: 5px 9px; font-size: 14px; white-space: nowrap; }
  main { padding: 10px 12px; }
  .card { padding: 12px; }
  button { padding: 7px 10px; }
  .bubble.you { width: 100%; max-width: 100%; }
}