/* === VT Math Practice Styles === */
:root{
  --bg:#0f1115; --panel:#171a21; --accent:#7dd3fc; --accent2:#f9a8d4;
  --text:#e5e7eb; --muted:#8b93a3; --skin:#f2c9a0;
  --green:#4ade80; --red:#f87171; --amber:#fbbf24; --purple:#c084fc;
}
*{box-sizing:border-box; margin:0; padding:0;}
body{
  margin:0; height:100vh; background:var(--bg); color:var(--text);
  font-family: -apple-system, "Segoe UI", Roboto, sans-serif;
  display:flex; overflow:hidden;
}

/* ── LEFT: AVATAR STAGE ── */
.stage{
  width:35%; min-width:280px; display:flex; flex-direction:column;
  align-items:center; justify-content:center;
  background: radial-gradient(circle at 50% 30%, #1c2029, #0b0d12 75%);
  border-right:1px solid #22262f; position:relative;
}
.stage .status-line{ position:absolute; top:16px; left:18px; font-size:12px; color:var(--muted); display:flex; align-items:center; gap:8px; }
.dot{ width:7px;height:7px;border-radius:50%; background:var(--green); box-shadow:0 0 8px var(--green); }
svg#face{ width:min(48vh,320px); overflow:visible; }
.faceGroup{ transform-origin: 100px 110px; animation: breathe 4s ease-in-out infinite; }
@keyframes breathe{ 0%,100%{transform:translateY(0) scale(1);} 50%{transform:translateY(-3px) scale(1.008);} }
.expr{ opacity:0; transition: opacity .3s ease; }
.expr.active{ opacity:1; }
.mouth-talk{ transform-origin:100px 145px; animation:none; }
.talking .mouth-talk{ animation: talk 0.26s ease-in-out infinite; }
@keyframes talk{ 0%,100%{transform:scaleY(0.35);} 50%{transform:scaleY(1);} }
.blink{ animation: blink 5s infinite; transform-origin:center; }
@keyframes blink{ 0%,96%,100%{transform:scaleY(1);} 98%{transform:scaleY(0.06);} }
.emotion-tag{ position:absolute; bottom:68px; left:50%; transform:translateX(-50%); font-size:11px; color:var(--muted); letter-spacing:.05em; text-transform:uppercase; }
.voice-row{ position:absolute; bottom:16px; left:50%; transform:translateX(-50%); display:flex; gap:8px; align-items:center; }
.voice-row select, .voice-row button{ background:var(--panel); color:var(--text); border:1px solid #262b35; border-radius:8px; padding:5px 8px; font-size:11px; cursor:pointer; }
.voice-row select{ max-width:200px; }
.ghost.muted{ color:var(--accent2); border-color:var(--accent2); }

/* ── RIGHT: PANEL ── */
.panel{ flex:1; display:flex; flex-direction:column; overflow:hidden; }
header{
  padding:14px 20px; border-bottom:1px solid #22262f;
  display:flex; align-items:center; gap:12px; flex-wrap:wrap;
}
header h2{ font-size:15px; color:var(--accent); white-space:nowrap; }
.student-badge{
  background:var(--panel); border:1px solid #262b35; border-radius:8px;
  padding:5px 10px; font-size:12px; position:relative; display:flex; align-items:center; gap:6px;
}
.student-badge input{ background:transparent; color:var(--text); border:none; font-size:12px; outline:none; width:100px; }
.student-badge input::placeholder{color:var(--muted);}
.student-badge .name-list-btn{ background:transparent; border:none; color:var(--muted); cursor:pointer; font-size:13px; padding:0 2px; }
.student-badge .name-list-btn:hover{color:var(--text);}
.name-dropdown{ position:absolute; top:100%; left:0; right:0; background:var(--panel); border:1px solid #262b35; border-radius:0 0 8px 8px; z-index:10; max-height:140px; overflow-y:auto; display:none; }
.name-dropdown.open{display:block;}
.name-dropdown .name-opt{ padding:6px 10px; cursor:pointer; font-size:11px; color:var(--muted); }
.name-dropdown .name-opt:hover{background:#1a1d25; color:var(--text);}
.name-dropdown .name-opt .del-btn{ float:right; color:var(--red); opacity:0; transition:opacity .15s; }
.name-dropdown .name-opt:hover .del-btn{opacity:1;}

/* ── MAIN AREA ── */
.main-area{ flex:1; overflow-y:auto; padding:20px; display:flex; flex-direction:column; gap:14px; }

/* ── LEVEL CARDS ── */
.level-card.unlocked:hover{ transform:translateY(-2px); box-shadow:0 4px 12px rgba(125,211,252,0.15); }

/* ── QUESTION ── */
.question-card{ background:var(--panel); border:1px solid #262b35; border-radius:14px; padding:20px 24px; text-align:center; }
.question-card .q-label{ font-size:11px; color:var(--muted); margin-bottom:6px; text-transform:uppercase; letter-spacing:.06em; }
.question-card .q-text{ font-size:26px; font-weight:700; color:var(--text); }
.question-card .q-hint{ font-size:12px; color:var(--amber); margin-top:6px; }

/* ── ANSWER CARDS ── */
.answer-card{
  background:linear-gradient(135deg, #1a2030, #1f2a3a); border:2px solid #2a3548;
  border-radius:16px; padding:22px 14px; text-align:center; font-size:26px; font-weight:800;
  cursor:pointer; transition: all .18s cubic-bezier(.4,0,.2,1); user-select:none;
  position:relative; overflow:hidden; min-height:70px; display:flex;
  align-items:center; justify-content:center;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}
.answer-card::before{
  content:''; position:absolute; top:0;left:0;right:0;height:2px;
  background:linear-gradient(90deg, transparent, var(--accent), transparent); opacity:0; transition:opacity .2s;
}
.answer-card:hover{
  border-color:var(--accent); background:linear-gradient(135deg, #1e2a3a, #233040);
  transform:translateY(-3px) scale(1.03);
  box-shadow: 0 6px 20px rgba(125,211,252,0.15);
}
.answer-card:hover::before{ opacity:1; }
.answer-card:active{ transform:scale(0.96); transition:transform .08s; }

.answer-card.correct-flash{
  border-color:var(--green); background:linear-gradient(135deg, #0a2a10, #0d3a18);
  animation: correctPop .5s cubic-bezier(.4,0,.2,1); box-shadow:0 0 24px rgba(74,222,128,0.3);
}
.answer-card.wrong-flash{
  border-color:var(--red); background:linear-gradient(135deg, #2a0a0a, #3a0d0d);
  animation: wrongShake .4s ease; box-shadow:0 0 20px rgba(248,113,113,0.2);
}
@keyframes correctPop{ 0%{transform:scale(1);} 30%{transform:scale(1.12);} 100%{transform:scale(1);} }
@keyframes wrongShake{ 0%,100%{transform:translateX(0);} 20%{transform:translateX(-8px);} 40%{transform:translateX(8px);} 60%{transform:translateX(-5px);} 80%{transform:translateX(5px);} }

/* ── CARD NUMBER ACCENT ── */
.answer-card .card-num{
  position:absolute; top:4px; right:8px; font-size:9px; color:var(--muted); opacity:0.4;
}

/* ── SCORE ── */
.score-bar{ display:flex; gap:10px; justify-content:center; flex-wrap:wrap; }
.score-item{ background:var(--panel); border:1px solid #262b35; border-radius:10px; padding:8px 14px; text-align:center; min-width:70px; }
.score-item .val{ font-size:18px; font-weight:700; }
.score-item .lbl{ font-size:10px; color:var(--muted); text-transform:uppercase; letter-spacing:.04em; }
.score-item .val.green{color:var(--green);}
.score-item .val.amber{color:var(--amber);}
.score-item .val.purple{color:var(--purple);}

/* ── BUTTONS ── */
.btn-start{
  background:var(--accent); color:#062023; border:none; border-radius:10px;
  padding:10px 20px; font-weight:700; font-size:13px; cursor:pointer; transition: filter .2s;
}
.btn-start:hover{ filter:brightness(1.15); }
.btn-ctrl{
  background:var(--panel); color:var(--muted); border:1px solid #262b35;
  border-radius:8px; padding:6px 14px; font-size:12px; cursor:pointer;
}
.btn-ctrl:hover{ color:var(--text); border-color:var(--muted); }

/* ── LEADERBOARD BUTTON ── */
.btn-lb{
  background:var(--amber); color:#000; border:none; border-radius:8px;
  padding:6px 12px; font-weight:600; font-size:12px; cursor:pointer;
}

/* ── LANGUAGE SELECT ── */
.lang-select{
  background:var(--panel); color:var(--text); border:1px solid #262b35;
  border-radius:8px; padding:6px 8px; font-size:12px; cursor:pointer; max-width:110px;
}

/* ── MIC BUTTON (voice answer) ── */
.stt-box{
  display:flex; flex-direction:column; align-items:center; gap:8px;
  margin:4px 0 8px; text-align:center;
}
.btn-mic{
  width:64px; height:64px; border-radius:50%; border:3px solid var(--accent);
  background:var(--panel); color:var(--text); font-size:26px; cursor:pointer;
  display:flex; align-items:center; justify-content:center; transition: all .15s; flex-shrink:0;
}
.btn-mic:hover{ transform:scale(1.05); }
.btn-mic.listening{
  background:var(--red); border-color:var(--red); color:#fff;
  animation: micPulse 1.1s ease-in-out infinite;
}
@keyframes micPulse{ 0%,100%{box-shadow:0 0 0 0 rgba(248,113,113,0.55);} 50%{box-shadow:0 0 0 16px rgba(248,113,113,0);} }
.stt-text{
  font-size:15px; font-weight:600; color:var(--muted); min-height:22px; line-height:1.35;
  max-width:90%; margin:0 auto;
}

/* ── TIMERS ── */
.timer-row{
  display:flex; justify-content:center; align-items:center; gap:16px;
  margin-bottom:6px; min-height:22px;
}
.total-timer{ font-size:13px; color:var(--muted); font-variant-numeric: tabular-nums; }
.q-timer{ font-size:16px; font-weight:800; color:var(--amber); font-variant-numeric: tabular-nums; }
.q-timer.urgent{ color:var(--red); animation: blink 1s infinite; }
@keyframes blink{ 0%,100%{opacity:1;} 50%{opacity:0.4;} }

/* ── MOBILE / SMALL SCREEN (portrait): avatar on top, panel below ── */
@media (max-width: 820px){
  body{ flex-direction:column; height:100dvh; }
  .stage{
    width:100%; min-width:0; height:32vh; min-height:170px;
    border-right:none; border-bottom:1px solid #22262f;
  }
  svg#face{ width:min(26vh,190px); }
  .emotion-tag{ bottom:44px; }
  .voice-row{ bottom:6px; gap:4px; width:100%; justify-content:center; flex-wrap:wrap; }
  .voice-row select{ max-width:96px; font-size:10px; padding:4px 4px; }
  .voice-row button{ font-size:10px; padding:4px 6px; }
  .panel{ flex:1; min-height:0; }
  header{ padding:10px 12px; gap:8px; }
  header h2{ font-size:13px; }
  .student-badge input{ width:80px; }
  .main-area{ padding:14px 10px; gap:10px; }
  .question-card{ padding:16px 14px; }
  .question-card .q-text{ font-size:22px; }
  .answer-card{ font-size:22px; min-height:62px; padding:18px 10px; }
}