:root {
  --bg: #0e1116;
  --bg-soft: #161b22;
  --card: #1a2029;
  --line: #2a323d;
  --fg: #e6edf3;
  --muted: #9aa7b4;
  --accent: #4da3ff;
  --accent-2: #7c5cff;
  --ok: #3fb950;
  --warn: #d29922;
  --bad: #f85149;
  --radius: 14px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: radial-gradient(1200px 600px at 80% -10%, #1b2740 0%, var(--bg) 55%);
  color: var(--fg);
  font: 15px/1.6 system-ui, "Segoe UI", Roboto, sans-serif;
  min-height: 100vh;
}

/* ---------- layout ---------- */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  gap: 16px; flex-wrap: wrap;
  padding: 14px 20px;
  background: rgba(14, 17, 22, .8);
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 20;
  backdrop-filter: blur(10px);
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand .logo { font-size: 26px; }
.brand b { display: block; letter-spacing: .2px; }
.brand small { color: var(--muted); font-size: 12px; }

main { max-width: 1060px; margin: 0 auto; padding: 22px 18px 70px; }
footer { text-align: center; color: var(--muted); padding: 22px; }

.view { display: none; }
.view.active { display: block; animation: fade .25s ease; }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } }

h1 { font-size: 24px; margin: 6px 0 10px; }
h3 { margin: 18px 0 8px; font-size: 15px; }
.muted { color: var(--muted); }
.hidden { display: none !important; }
.row { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 10px; }

/* ---------- buttons ---------- */
button { font: inherit; cursor: pointer; border-radius: 10px; transition: .15s; }
.tab, .chip, .subtab, .ghost {
  background: var(--bg-soft); color: var(--fg);
  border: 1px solid var(--line); padding: 8px 14px;
}
.tab:hover, .chip:hover, .subtab:hover, .ghost:hover { border-color: var(--accent); }
.tab.active, .chip.active, .subtab.active {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border-color: transparent; color: #fff; font-weight: 600;
}
.tabs, .chips, .subtabs { display: flex; gap: 8px; flex-wrap: wrap; }
.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; border: 0; padding: 10px 18px; font-weight: 600;
}
.primary:hover { filter: brightness(1.12); }
.ghost.danger { color: var(--bad); border-color: #4a2a2a; }
.back { background: none; border: 0; color: var(--accent); padding: 4px 0; margin-bottom: 8px; }
.linkbtn { background: none; border: 0; color: var(--accent); text-decoration: underline; padding: 0; }

/* ---------- forms ---------- */
input, select, textarea {
  font: inherit; width: 100%;
  background: #0d1117; color: var(--fg);
  border: 1px solid var(--line); border-radius: 10px; padding: 9px 12px;
}
input:focus, select:focus, textarea:focus { outline: 2px solid var(--accent); border-color: transparent; }
label { display: block; margin: 12px 0 0; color: var(--muted); font-size: 13px; }
label > input, label > select, label > textarea { margin-top: 5px; color: var(--fg); }
input[type=range] { padding: 0; }
.radio { display: flex; align-items: baseline; gap: 8px; color: var(--fg); }
.radio input { width: auto; }
.radio small { color: var(--muted); }

.card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 16px 18px; margin: 14px 0;
}
.toolbar { display: flex; flex-direction: column; gap: 12px; margin-bottom: 18px; }
.msg { font-size: 13px; min-height: 18px; }
.msg.ok { color: var(--ok); }
.msg.bad { color: var(--bad); }

/* ---------- library ---------- */
.grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
.lesson-card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px; cursor: pointer; text-align: left; color: var(--fg);
  display: flex; flex-direction: column; gap: 6px; min-height: 140px;
}
.lesson-card:hover { border-color: var(--accent); transform: translateY(-2px); }
.lesson-card b { font-size: 16px; }
.lesson-card .meta { margin-top: auto; display: flex; gap: 8px; align-items: center; flex-wrap: wrap; }
.badge {
  font-size: 11px; font-weight: 700; letter-spacing: .5px;
  padding: 3px 9px; border-radius: 999px;
  background: #1f6feb33; color: #79c0ff; border: 1px solid #1f6feb55;
}
.badge.draft { background: #d2992233; color: #e3b341; border-color: #d2992255; }
.badge.done { background: #3fb95033; color: #56d364; border-color: #3fb95055; }
.empty { text-align: center; color: var(--muted); padding: 40px; }

/* ---------- lesson ---------- */
.lesson-head { display: flex; justify-content: space-between; gap: 20px; align-items: flex-start; flex-wrap: wrap; }
.lesson-head h1 { margin: 8px 0 4px; }
.lesson-progress { text-align: center; color: var(--muted); font-size: 12px; }
.ring {
  width: 64px; height: 64px; border-radius: 50%;
  display: grid; place-items: center; font-weight: 700; font-size: 17px; color: var(--fg);
  background: conic-gradient(var(--accent) calc(var(--p, 0) * 1%), #2a323d 0);
  position: relative; margin: 0 auto 4px;
}
.ring::before { content: ""; position: absolute; inset: 6px; border-radius: 50%; background: var(--bg); }
.ring span { position: relative; }
.subtabs { margin: 18px 0; }
.pane { display: none; }
.pane.active { display: block; }

.vocab-list, .pattern-list { display: grid; gap: 8px; }
.vocab-item, .pattern-item {
  background: var(--card); border: 1px solid var(--line); border-radius: 10px;
  padding: 10px 14px; display: flex; gap: 12px; align-items: flex-start;
}
.vocab-item .en { font-weight: 600; }
.vocab-item .ipa { color: var(--accent); font-size: 13px; }
.vocab-item .vi, .pattern-item .vi { color: var(--muted); font-size: 13px; }
.speak { background: none; border: 1px solid var(--line); border-radius: 8px; padding: 4px 9px; color: var(--fg); flex: 0 0 auto; }
.speak:hover { border-color: var(--accent); }
.tip { background: #1f6feb18; border-left: 3px solid var(--accent); padding: 10px 14px; border-radius: 0 10px 10px 0; margin: 8px 0; }

/* ---------- drill ---------- */
.drill-row {
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  padding: 12px 14px; margin-bottom: 10px;
}
.drill-row.done { border-color: var(--ok); }
.drill-row .en { font-size: 16px; }
.drill-row .vi { color: var(--muted); font-size: 13px; margin-top: 2px; }
.drill-row .actions { display: flex; gap: 8px; margin-top: 10px; flex-wrap: wrap; align-items: center; }
.score-pill { font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 999px; border: 1px solid var(--line); }
.score-pill.good { color: var(--ok); border-color: #3fb95055; background: #3fb95022; }
.score-pill.mid { color: var(--warn); border-color: #d2992255; background: #d2992222; }
.score-pill.low { color: var(--bad); border-color: #f8514955; background: #f8514922; }
.w-ok { color: var(--ok); }
.w-bad { color: var(--bad); text-decoration: underline wavy var(--bad); }
.heard { font-size: 13px; color: var(--muted); margin-top: 6px; }

/* ---------- chat ---------- */
.talk-modes { display: grid; gap: 8px; background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; }
.roleinfo { color: var(--muted); font-size: 13px; margin: 12px 0; }
.chat {
  background: #0d1117; border: 1px solid var(--line); border-radius: 12px;
  padding: 14px; min-height: 260px; max-height: 46vh; overflow-y: auto;
  display: flex; flex-direction: column; gap: 10px;
}
.bubble { max-width: 78%; padding: 10px 14px; border-radius: 14px; line-height: 1.5; }
.bubble.ai { background: var(--card); border: 1px solid var(--line); border-bottom-left-radius: 4px; align-self: flex-start; }
.bubble.me { background: linear-gradient(135deg, #1f6feb, #6b46e5); border-bottom-right-radius: 4px; align-self: flex-end; }
.bubble.sys { align-self: center; background: none; color: var(--muted); font-size: 12px; text-align: center; max-width: 100%; }
.bubble.coach {
  align-self: flex-start; background: #d2992216; border: 1px solid #d2992255;
  border-left: 3px solid var(--warn); border-radius: 4px 14px 14px 4px; max-width: 88%; font-size: 14px;
}
.bubble.coach .fb { border-top-color: #d2992244; }
.bubble .vi { display: block; font-size: 12px; opacity: .72; margin-top: 4px; }
.bubble .fb { display: block; font-size: 12px; margin-top: 6px; padding-top: 6px; border-top: 1px solid #ffffff22; }

.mic-bar { display: flex; gap: 14px; align-items: flex-start; margin-top: 14px; flex-wrap: wrap; }
.mic {
  width: 104px; height: 104px; border-radius: 50%; border: 0; flex: 0 0 auto;
  background: linear-gradient(135deg, var(--accent), var(--accent-2)); color: #fff;
  font-size: 28px; display: grid; place-items: center; gap: 2px;
}
.mic span { font-size: 11px; font-weight: 600; }
.mic:disabled { opacity: .45; cursor: not-allowed; }
.mic.listening { animation: pulse 1.1s infinite; background: linear-gradient(135deg, #f85149, #d29922); }
@keyframes pulse { 50% { box-shadow: 0 0 0 14px #f8514922; } }
.mic-side { flex: 1 1 260px; display: grid; gap: 8px; }

/* ---------- thanh phát âm thanh dính đáy trang ---------- */
.audio-bar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 35;
  display: flex; align-items: center; gap: 10px;
  padding: 10px 16px calc(10px + env(safe-area-inset-bottom));
  background: rgba(14, 17, 22, .96);
  border-top: 1px solid var(--line);
  backdrop-filter: blur(10px);
  animation: audioBarIn .18s ease-out;
}
.audio-bar-icon { flex: 0 0 auto; font-size: 17px; animation: pulse2 1.2s ease-in-out infinite; }
.audio-bar-text {
  flex: 1 1 auto; min-width: 0;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  font-size: 14px; color: var(--fg);
}
.audio-bar-stop {
  flex: 0 0 auto; cursor: pointer;
  background: var(--card); color: var(--fg); border: 1px solid var(--line);
  border-radius: 999px; padding: 7px 14px; font-size: 13px; font-weight: 600;
}
.audio-bar-stop:hover { border-color: var(--bad); color: var(--bad); }
@keyframes pulse2 { 50% { opacity: .35; } }
@keyframes audioBarIn { from { transform: translateY(100%); } to { transform: translateY(0); } }
.interim { min-height: 42px; color: var(--muted); font-style: italic; background: var(--card); border: 1px solid var(--line); border-radius: 10px; padding: 9px 12px; }
.mic-actions { display: flex; gap: 6px; flex-wrap: wrap; }
.mic-actions .ghost { padding: 6px 10px; font-size: 13px; }

/* ---------- dialogue player ---------- */
.player { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; }
.player-bar { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin-bottom: 8px; }
.player-bar label { margin: 0; display: flex; align-items: center; gap: 7px; white-space: nowrap; }
.player-bar input[type=range] { width: 108px; }
.player-bar input[type=checkbox] { width: auto; }
.player-bar select { width: auto; min-width: 150px; }
.p-loop { color: var(--fg); cursor: pointer; }
.script { list-style: none; margin: 10px 0 0; padding: 0; max-height: 260px; overflow-y: auto; display: grid; gap: 4px; }
.script .line {
  padding: 7px 10px; border-radius: 8px; cursor: pointer;
  border-left: 3px solid transparent; transition: .12s;
}
.script .line:hover { background: var(--bg-soft); }
.script .line.theirs { border-left-color: var(--accent); }
.script .line.mine { border-left-color: var(--accent-2); }
.script .line.now { background: #1f6feb28; border-left-color: var(--warn); }
.script .who { display: block; font-size: 11px; color: var(--muted); }
.script .en { font-size: 14.5px; }
.script .vi { display: block; font-size: 12px; color: var(--muted); }

/* ---------- mindmap ---------- */
.mindmap-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 12px; background: #0d1117; padding: 6px; }
.mindmap { display: block; min-width: 720px; }
.mindmap .leaf { cursor: pointer; }
.mindmap .leaf:hover rect { stroke: var(--accent); fill: var(--bg-soft); }
.mindmap .leaf:focus { outline: none; }
.mindmap .leaf:focus rect { stroke: var(--accent); stroke-width: 2; }

/* ---------- 10 hội thoại mẫu ---------- */
.pack-list { display: grid; gap: 8px; }
.pack { background: var(--card); border: 1px solid var(--line); border-radius: 12px; }
.pack[open] { border-color: var(--accent); }
.pack > summary {
  display: flex; align-items: center; gap: 10px;
  padding: 12px 14px; cursor: pointer; list-style: none;
}
.pack > summary::-webkit-details-marker { display: none; }
.pack-n {
  flex: 0 0 auto; width: 24px; height: 24px; border-radius: 50%;
  display: grid; place-items: center; font-size: 12px; font-weight: 700;
  background: #1f6feb33; color: #79c0ff; border: 1px solid #1f6feb55;
}
.pack-title { flex: 1 1 auto; font-weight: 600; }
.pack-score { font-size: 12px; font-weight: 700; padding: 2px 9px; border-radius: 999px; border: 1px solid var(--line); }
.pack-score.good { color: var(--ok); border-color: #3fb95055; background: #3fb95022; }
.pack-score.mid { color: var(--warn); border-color: #d2992255; background: #d2992222; }
.pack-score.low { color: var(--bad); border-color: #f8514955; background: #f8514922; }
.pack-body { padding: 0 14px 14px; }
.pack-situation { color: var(--muted); font-size: 13px; margin: 0 0 10px; }
.pack-body h4 { margin: 16px 0 8px; font-size: 14px; }
.pack-row { background: var(--bg-soft); }

/* ---------- 100 bài tập ---------- */
.quiz-head { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
.quiz-head .row { margin: 0; }
.quiz-progress { height: 5px; background: var(--line); border-radius: 999px; margin: 12px 0 16px; overflow: hidden; }
.quiz-progress .bar {
  height: 100%; width: 0;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  transition: width .25s ease;
}
.quiz-card { margin: 0; }
.quiz-kind {
  font-size: 11px; font-weight: 700; letter-spacing: .5px; text-transform: uppercase;
  color: var(--accent); margin-bottom: 8px;
}
.quiz-card .q { font-size: 17px; line-height: 1.45; margin-bottom: 4px; }
.quiz-card .vi { color: var(--muted); font-size: 13px; }
.quiz-card .choices { margin-top: 14px; }
.quiz-after { margin-top: 14px; padding-top: 12px; border-top: 1px solid var(--line); }
.verdict { font-weight: 700; margin-bottom: 8px; }
.quiz-after .why { color: var(--muted); font-size: 13px; margin-bottom: 10px; }

.order-slot {
  min-height: 46px; margin: 14px 0 10px; padding: 11px 13px;
  background: #0d1117; border: 1px dashed var(--line); border-radius: 10px;
  font-size: 16px; line-height: 1.5;
}
.order-bank { display: flex; flex-wrap: wrap; gap: 7px; }
.word {
  background: var(--bg-soft); color: var(--fg); border: 1px solid var(--line);
  padding: 9px 13px; font-size: 15px;
}
.word:hover:not(:disabled) { border-color: var(--accent); }
.word:disabled { opacity: .3; cursor: default; }
.homework { color: var(--muted); font-size: 14px; }

/* ---------- so sanh tu vung: dong nghia, trai nghia, de nham ---------- */
.wr-list { display: grid; gap: 10px; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }
.wr-list.compact { grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); margin-top: 10px; }
.wr-card {
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  padding: 12px 14px; display: flex; flex-direction: column; gap: 8px;
  border-left: 3px solid var(--accent);
}
.wr-card.wr-antonym { border-left-color: var(--warn); }
.wr-card.wr-confusable { border-left-color: var(--bad); }
.wr-top { display: flex; gap: 6px; }
.wr-words { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; }
.wr-word {
  background: var(--bg-soft); color: var(--fg); border: 1px solid var(--line);
  padding: 6px 11px; border-radius: 8px; text-align: left; font-size: 14px;
}
.wr-word:hover { border-color: var(--accent); }
.wr-word i { display: block; font-style: normal; color: var(--muted); font-size: 12px; margin-top: 2px; }
.wr-vs { color: var(--muted); font-weight: 700; flex: 0 0 auto; }
.wr-note { color: var(--muted); font-size: 13px; line-height: 1.5; }

/* ---------- sổ tay: thành ngữ & cách nói bản xứ ---------- */
.pb-list { display: grid; gap: 10px; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); }
.pb-list.compact { grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); margin-top: 10px; }
.pb-card {
  background: var(--card); border: 1px solid var(--line);
  border-left: 3px solid var(--accent-2); border-radius: 0 12px 12px 0;
  padding: 12px 14px; display: flex; flex-direction: column; gap: 5px;
}
.pb-top { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.pb-en { font-size: 16px; font-weight: 600; flex: 1 1 auto; }
.pb-vi { color: var(--accent); font-size: 14px; }
.pb-note { color: var(--muted); font-size: 13px; line-height: 1.5; }
.pb-example {
  font-style: italic; font-size: 13.5px; color: var(--fg);
  background: #0d1117; border-radius: 8px; padding: 7px 10px; cursor: pointer;
}
.pb-example:hover { outline: 1px solid var(--accent); }
.pb-card .actions { display: flex; gap: 6px; flex-wrap: wrap; align-items: center; margin-top: 4px; }
.pb-card .actions .ghost { padding: 5px 9px; font-size: 12.5px; }
.chips.scroll-x { flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none; padding-bottom: 4px; }
.chips.scroll-x::-webkit-scrollbar { display: none; }

/* ---------- nghĩa từng từ (word by word) ---------- */
.gloss {
  display: flex; flex-wrap: wrap; gap: 6px;
  margin-top: 10px; padding: 10px;
  background: #0d1117; border: 1px solid var(--line); border-radius: 10px;
}
.gw {
  display: flex; flex-direction: column; align-items: center;
  padding: 5px 9px; border-radius: 8px; background: var(--bg-soft);
  border: 1px solid var(--line); min-width: 52px;
}
.gw b { font-size: 14px; cursor: pointer; }
.gw b:hover { color: var(--accent); }
.gw i { font-size: 11.5px; color: var(--muted); font-style: normal; text-align: center; }
.gw.unknown { opacity: .55; border-style: dashed; }

/* ---------- nói như người bản xứ ---------- */
.swap {
  background: var(--card); border: 1px solid var(--line);
  border-left: 3px solid var(--accent-2); border-radius: 0 12px 12px 0;
  padding: 11px 14px; margin-bottom: 9px;
}
.swap-pair { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; }
.swap-bookish { color: var(--muted); text-decoration: line-through; }
.swap-arrow { color: var(--accent-2); font-weight: 700; }
.swap-native {
  background: #7c5cff22; border: 1px solid #7c5cff66; color: var(--fg);
  font-weight: 600; padding: 5px 11px; border-radius: 8px;
}
.swap-native:hover { border-color: var(--accent-2); background: #7c5cff33; }
.swap .vi { color: var(--muted); font-size: 13px; margin-top: 7px; }

/* ---------- variations & culture ---------- */
.variation {
  background: var(--card); border: 1px solid var(--line);
  border-radius: 12px; padding: 12px 14px; margin-bottom: 10px;
}
.variation .vsit { font-size: 12px; color: var(--muted); margin-bottom: 6px; }
.variation .vrow { display: flex; align-items: center; gap: 9px; margin: 5px 0; }
.vtag {
  font-size: 10.5px; font-weight: 700; letter-spacing: .4px; text-transform: uppercase;
  padding: 2px 8px; border-radius: 999px; flex: 0 0 auto;
}
.vtag.formal { background: #1f6feb33; color: #79c0ff; border: 1px solid #1f6feb55; }
.vtag.casual { background: #3fb95033; color: #56d364; border: 1px solid #3fb95055; }
.variation .vi { margin-top: 7px; color: var(--muted); font-size: 13px; }
.tip.culture { border-left-color: var(--ok); background: #3fb95014; }

/* ---------- listening comprehension ---------- */
.listen-card .passage {
  background: #0d1117; border: 1px solid var(--line); border-radius: 10px;
  padding: 12px 14px; margin: 12px 0; line-height: 1.7;
}
.listen-card .passage .vi { color: var(--muted); font-size: 13px; margin-top: 8px; }
.quiz-q { margin: 14px 0; }
.quiz-q .q { margin-bottom: 8px; }
.choices { display: grid; gap: 6px; }
.choice {
  text-align: left; background: var(--bg-soft); color: var(--fg);
  border: 1px solid var(--line); padding: 9px 13px;
}
.choice:hover:not(:disabled) { border-color: var(--accent); }
.choice:disabled { cursor: default; opacity: .75; }
.choice.right { border-color: var(--ok); background: #3fb95022; color: #56d364; opacity: 1; }
.choice.wrong { border-color: var(--bad); background: #f8514922; color: #ff7b72; opacity: 1; }
.quiz-q .why { margin-top: 7px; font-size: 13px; color: var(--muted); }
.listen-score { margin-top: 10px; font-size: 13px; font-weight: 600; }

/* ---------- dictation ---------- */
.listen-row .masked { font-family: "Cascadia Code", Consolas, monospace; color: var(--muted); letter-spacing: 2px; }
.listen-row.done .masked { color: var(--ok); }
.dictation { margin-top: 8px; }
.listen-row .reveal { margin-top: 8px; font-size: 16px; }

/* ---------- quiz ---------- */
.quiz-item { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; margin-bottom: 10px; }
.quiz-item .q { margin-bottom: 8px; }
.quiz-item .reveal { color: var(--ok); font-weight: 600; margin-top: 8px; }

/* ---------- generator ---------- */
.gen-grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); align-items: start; }
.code {
  background: #0d1117; border: 1px solid var(--line); border-radius: 10px;
  padding: 12px; overflow-x: auto; font-size: 12.5px; white-space: pre-wrap; word-break: break-word;
}
.code.scroll { max-height: 260px; overflow-y: auto; }
.roadmap { margin-top: 12px; max-height: 420px; overflow-y: auto; }
.roadmap h4 { margin: 14px 0 4px; font-size: 13px; color: var(--accent); }
.roadmap-list { list-style: none; margin: 0; padding: 0; display: grid; gap: 3px; font-size: 13.5px; }
.roadmap-list a { color: var(--fg); }
.roadmap-list .todo { color: var(--muted); }
.roadmap-list code { font-size: 11.5px; color: var(--warn); }
code { font-family: "Cascadia Code", Consolas, monospace; }

/* =======================================================================
   ĐIỆN THOẠI
   Học trên điện thoại là đường dùng chính, nên đây không phải vài chỗ chỉnh
   cho vừa mà là bố cục riêng: thanh micro dính đáy trong tầm ngón tay, tab
   cuộn ngang thay vì xuống dòng, và mọi vùng bấm đủ lớn.
   ===================================================================== */
@media (max-width: 720px) {
  main { padding: 14px 12px 96px; }          /* chỗ trống dưới cho thanh micro */
  h1 { font-size: 20px; }

  .topbar { padding: 10px 12px; gap: 10px; }
  .brand small { display: none; }
  .tabs { width: 100%; }
  #mainNav .tab {
    flex: 1 1 0; min-width: 0; padding: 9px 4px;
    font-size: 11.5px; text-align: center;
    white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  }

  /* Tab bài học: cuộn ngang, không xuống dòng thành ba tầng. */
  .subtabs {
    flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none;
    margin: 14px -12px; padding: 0 12px 4px;
  }
  .subtabs::-webkit-scrollbar { display: none; }
  .subtab { flex: 0 0 auto; white-space: nowrap; }
  .chip { white-space: nowrap; }

  .chips { flex-wrap: nowrap; overflow-x: auto; scrollbar-width: none; padding-bottom: 4px; }
  .chips::-webkit-scrollbar { display: none; }

  .grid { grid-template-columns: 1fr; }
  .gen-grid { grid-template-columns: 1fr; }
  /* Tiêu đề và điểm nằm cùng một hàng, không để vòng điểm rơi xuống dòng riêng. */
  .lesson-head { flex-wrap: nowrap; align-items: flex-start; gap: 12px; }
  .lesson-head > div:first-child { min-width: 0; flex: 1 1 auto; }
  .lesson-progress { flex: 0 0 auto; }
  .lesson-progress small { font-size: 10px; }
  .ring { width: 52px; height: 52px; font-size: 14px; }
  .card { padding: 13px 14px; }

  /* iOS zoom vào ô nhập nếu chữ dưới 16px. */
  input, select, textarea { font-size: 16px; }

  /* Thanh micro dính đáy màn hình. */
  .mic-bar {
    position: fixed; left: 0; right: 0; bottom: 0; z-index: 30;
    margin: 0; padding: 10px 12px calc(10px + env(safe-area-inset-bottom));
    background: rgba(14, 17, 22, .96); border-top: 1px solid var(--line);
    backdrop-filter: blur(10px);
    display: grid; grid-template-columns: 64px 1fr; gap: 10px; align-items: center;
  }
  .mic { width: 64px; height: 64px; font-size: 22px; }
  .mic span { display: none; }
  .interim { min-height: 0; padding: 6px 10px; font-size: 13px; }
  /* Mic-bar cũng dính đáy ở tab Hội thoại 1-1 — đẩy thanh phát âm lên trên nó. */
  body:has(#pane-talk.active) .audio-bar:not(.hidden) { bottom: 84px; }
  .mic-actions .ghost { padding: 7px 10px; }
  #typeFallback { display: none; }           /* trên điện thoại thì dùng micro */
  .chat { max-height: 52vh; }
  .bubble { max-width: 92%; }

  .player-bar { gap: 8px; }
  .player-bar label { font-size: 12px; }
  .player-bar input[type=range] { width: 88px; }
  .player-bar select { min-width: 0; max-width: 58vw; }
  .script { max-height: 42vh; }

  .vocab-item, .pattern-item { padding: 10px 12px; }
  .speak { padding: 7px 11px; }
  .choice { padding: 12px 14px; }            /* vùng bấm trắc nghiệm to hơn */
  .word { padding: 11px 14px; font-size: 16px; }
  .gw { min-width: 46px; padding: 4px 7px; }
  .gw b { font-size: 13px; }
  .gw i { font-size: 10.5px; }
  .quiz-card .q { font-size: 16px; }
  .pack > summary { padding: 13px 12px; }
  .pb-list, .pb-list.compact { grid-template-columns: 1fr; }
  .pb-en { font-size: 15px; }
  .wr-list, .wr-list.compact { grid-template-columns: 1fr; }
  .wr-word { font-size: 13.5px; }
  .pack-body { padding: 0 12px 12px; }
  .variation .vrow { flex-wrap: wrap; }
  .code { font-size: 11.5px; }
  .mindmap-wrap { margin: 0 -12px; border-radius: 0; border-left: 0; border-right: 0; }
}

@media (max-width: 420px) {
  .mic-bar { grid-template-columns: 56px 1fr; }
  .mic { width: 56px; height: 56px; font-size: 20px; }
  .mic-actions .ghost { font-size: 12px; padding: 6px 8px; }
}

/* Máy không có chuột: bỏ hiệu ứng hover dính lại sau khi chạm. */
@media (hover: none) {
  .lesson-card:hover { transform: none; border-color: var(--line); }
  .script .line:hover { background: none; }
}