:root {
  --bg: #f4f6f9;
  --panel: #ffffff;
  --ink: #12202f;
  --muted: #5b6b7c;
  --line: #dde3ea;
  --brand: #0f2a4a;
  --accent: #1f6fd1;
  --good: #1d7a46;
  --good-bg: #e7f5ec;
  --fix: #9a3b12;
  --fix-bg: #fdf0e8;
  --tip: #6a5300;
  --tip-bg: #fbf5df;
  --ptt: #1f6fd1;
  --ptt-live: #d1352b;
  color-scheme: light;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0c1622;
    --panel: #142233;
    --ink: #e8eef5;
    --muted: #9fb0c2;
    --line: #23364b;
    --brand: #cfe0f5;
    --accent: #6aa8f0;
    --good: #6fd39a;
    --good-bg: #133324;
    --fix: #f2a27a;
    --fix-bg: #3a2216;
    --tip: #e9cf72;
    --tip-bg: #33290f;
    --ptt: #2f7fe0;
    --ptt-live: #e0453a;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }
html, body { margin: 0; }
body {
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.45 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  -webkit-text-size-adjust: 100%;
}
button { font: inherit; color: inherit; }
[hidden] { display: none !important; }

.screen {
  max-width: 560px;
  margin: 0 auto;
  min-height: 100dvh;
  padding: calc(env(safe-area-inset-top) + 16px) 16px calc(env(safe-area-inset-bottom) + 16px);
  display: flex;
  flex-direction: column;
}

/* Home */
.top h1 { margin: 12px 0 2px; font-size: 30px; color: var(--brand); letter-spacing: -0.01em; }
.sub { margin: 0; color: var(--muted); }
.lead { margin: 20px 0 16px; }
.topics { display: grid; gap: 10px; }
.topic {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 18px; border: 1px solid var(--line); border-radius: 14px;
  background: var(--panel); text-align: left; cursor: pointer; font-weight: 600;
}
.topic small { font-weight: 400; color: var(--muted); }
.topic.mix { border-color: var(--accent); }
.topic:active { transform: scale(0.99); }
.note { margin-top: 16px; padding: 12px 14px; border-radius: 10px; background: var(--fix-bg); color: var(--fix); }
.fine { color: var(--muted); font-size: 14px; }

/* Drill */
.bar { display: flex; justify-content: space-between; align-items: center; }
.back { background: none; border: 0; padding: 8px 0; color: var(--accent); font-weight: 600; cursor: pointer; }
.score { color: var(--muted); font-size: 15px; }

.card {
  margin-top: 8px; padding: 20px 18px 16px; text-align: center;
  background: var(--panel); border: 1px solid var(--line); border-radius: 18px;
}
.ask { margin: 0; color: var(--muted); }
.value {
  margin: 6px 0 4px; font-size: clamp(38px, 12vw, 56px); font-weight: 700; letter-spacing: 0.03em;
  font-variant-numeric: tabular-nums; color: var(--brand); word-break: break-word;
}
.hint-btn { background: none; border: 0; color: var(--accent); cursor: pointer; padding: 6px; font-size: 15px; }
.hint { margin: 4px 0 0; font-style: italic; }

.result { margin-top: 14px; padding: 16px 18px; border-radius: 16px; background: var(--panel); border: 1px solid var(--line); }
.result.good { background: var(--good-bg); border-color: transparent; }
.result.fix { background: var(--fix-bg); border-color: transparent; }
.result.tip { background: var(--tip-bg); border-color: transparent; }
.verdict { margin: 0 0 8px; font-weight: 700; font-size: 19px; }
.good .verdict { color: var(--good); }
.fix .verdict { color: var(--fix); }
.tip .verdict { color: var(--tip); }
.label { display: block; font-size: 13px; text-transform: uppercase; letter-spacing: 0.06em; color: var(--muted); }
.heard, .model { margin: 8px 0; }
#heard { font-style: italic; }
.feedback { margin: 8px 0; padding-left: 20px; }
.feedback li { margin: 4px 0; }
.actions { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; margin-top: 12px; }
.primary, .secondary { padding: 12px; border-radius: 12px; font-weight: 600; cursor: pointer; }
.primary { background: var(--accent); color: #fff; border: 0; }
.secondary { background: transparent; border: 1px solid var(--line); }
.linkish { margin-top: 10px; background: none; border: 0; color: var(--muted); text-decoration: underline; cursor: pointer; padding: 4px 0; font-size: 15px; }
.fix { display: grid; gap: 8px; margin-top: 8px; }
.fix input { font: inherit; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: var(--panel); color: var(--ink); }

/* Push to talk */
.ptt-wrap { margin-top: auto; padding-top: 20px; display: flex; flex-direction: column; align-items: center; gap: 10px; }
.status { margin: 0; color: var(--muted); min-height: 1.45em; text-align: center; }
.ptt {
  width: 112px; height: 112px; border-radius: 50%; border: 0; cursor: pointer;
  background: var(--ptt); color: #fff; display: grid; place-items: center;
  box-shadow: 0 6px 20px rgba(31, 111, 209, 0.35);
  touch-action: none; user-select: none; -webkit-user-select: none; -webkit-touch-callout: none;
  -webkit-tap-highlight-color: transparent;
  transition: transform 0.08s, background 0.15s;
}
.ptt svg { width: 46px; height: 46px; fill: currentColor; stroke: currentColor; }
.ptt.live { background: var(--ptt-live); transform: scale(1.08); box-shadow: 0 0 0 10px rgba(209, 53, 43, 0.18); }
.ptt.busy { opacity: 0.5; }
.ptt:disabled { cursor: default; }

/* Options on the home screen */
.switches { display: grid; gap: 8px; margin: 0 0 16px; }
.switch { display: flex; gap: 12px; align-items: flex-start; padding: 12px 14px; border-radius: 12px; background: var(--panel); border: 1px solid var(--line); cursor: pointer; }
.switch input { width: 22px; height: 22px; margin: 1px 0 0; accent-color: var(--accent); flex: none; }
.switch small { display: block; color: var(--muted); font-size: 14px; }

/* Speaker toggle in the drill bar */
.bar { gap: 8px; }
.bar .score { margin-left: auto; }
.icon-btn { width: 40px; height: 40px; border-radius: 10px; border: 1px solid var(--line); background: var(--panel); display: grid; place-items: center; cursor: pointer; }
.icon-btn svg { width: 22px; height: 22px; fill: var(--ink); stroke: var(--ink); }
.icon-btn[aria-pressed="true"] .mute, .icon-btn[aria-pressed="false"] .waves { display: none; }

/* General feedback sheet */
.sheet { border: 0; border-radius: 18px; padding: 20px; width: min(520px, calc(100vw - 32px)); background: var(--panel); color: var(--ink); }
.sheet::backdrop { background: rgba(0, 0, 0, 0.45); }
.sheet h2 { margin: 0 0 4px; font-size: 21px; }
.sheet textarea { width: 100%; font: inherit; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: var(--bg); color: var(--ink); }

/* Screens and modules */
.screen-title { margin: 8px 0 4px; font-size: 24px; color: var(--brand); }
.modules { margin: 20px 0 16px; }
.module { align-items: flex-start; gap: 12px; }
.module b { display: block; font-size: 18px; }
.module small { display: block; margin-top: 2px; font-weight: 400; }
.module i { font-style: normal; font-size: 13px; color: var(--muted); white-space: nowrap; margin-top: 3px; }

/* Module 1 */
.profile { display: grid; gap: 12px; margin-top: 8px; }
.profile label { display: grid; gap: 4px; font-weight: 600; }
.profile input, .profile select { font: inherit; font-weight: 400; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: var(--panel); color: var(--ink); }
.callsign-line { margin: 12px 0 0; }
.linkish.inline { margin: 0 0 0 6px; padding: 0; }
.situation { margin: 10px 0 6px; font-size: 19px; line-height: 1.4; text-align: left; }
.card.call { text-align: left; }
.card.call .ask { font-weight: 600; }
.sum-list { padding-left: 22px; }
.sum-list li { margin: 8px 0; }
.sum-list .mark { font-weight: 700; margin-right: 6px; }
.sum-list .ok { color: var(--good); }
.sum-list .tip { color: var(--tip); }
.sum-list .fix { color: var(--fix); }
.sum-list small { display: block; color: var(--muted); }

/* Help levels: script and listen-and-repeat */
.script { margin: 10px 0 4px; padding: 12px 14px; border-radius: 12px; background: var(--bg); border: 1px dashed var(--line); }
.script p { margin: 4px 0 0; font-size: 19px; line-height: 1.4; }
.listen { display: grid; gap: 6px; justify-items: start; margin-top: 8px; }
.flight { padding: 14px 16px; border: 1px solid var(--line); border-radius: 14px; background: var(--panel); display: grid; gap: 10px; }
.flight b { font-size: 18px; }
.flight small { display: block; color: var(--muted); }
.seg { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--line); border-radius: 10px; overflow: hidden; }
.seg button { border: 0; background: transparent; padding: 8px 4px; font-size: 14px; cursor: pointer; }
.seg button + button { border-left: 1px solid var(--line); }
.seg button[aria-pressed="true"] { background: var(--accent); color: #fff; font-weight: 600; }

/* "You keep doing X" drill suggestion */
.habit { margin: 12px 0 4px; padding: 12px 14px; border-radius: 12px; background: var(--panel); border: 1px solid var(--accent); }
.habit p { margin: 0 0 4px; }

/* Practice airport and grouped lessons */
.airport-line { display: grid; gap: 4px; margin: 0 0 14px; font-weight: 600; }
.airport-line select { font: inherit; font-weight: 400; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: var(--panel); color: var(--ink); }
.group-title { margin: 18px 0 2px; font-size: 15px; text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted); }