:root{--text:#86868c;--text-h:#0a0a0c;--bg:#fff;--border:#e4e4e7;--code-bg:#f5f5f6;--sans:Calibri, "Segoe UI", Tahoma, Roboto, sans-serif;font:15px/1.5 var(--sans);--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light dark;color:var(--text);background:var(--bg);font-synthesis:none;text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}@media (prefers-color-scheme:dark){:root{--lightningcss-light: ;--lightningcss-dark:initial;--text:#8b8b93;--text-h:#f5f5f6;--bg:#0b0b0d;--border:#232326;--code-bg:#17171a}}:root[data-theme=light]{--text:#86868c;--text-h:#0a0a0c;--bg:#fff;--border:#e4e4e7;--code-bg:#f5f5f6}:root[data-theme=dark]{--text:#8b8b93;--text-h:#f5f5f6;--bg:#0b0b0d;--border:#232326;--code-bg:#17171a}#root{box-sizing:border-box;background:var(--bg);flex-direction:column;width:100%;max-width:440px;min-height:100svh;margin:0 auto;display:flex}body{margin:0}.top-bar{align-items:center;gap:10px;margin-bottom:28px;display:flex}.lang-switch{gap:6px;display:flex}.dn-toggle{cursor:pointer;box-sizing:border-box;border:none;border-radius:999px;flex-shrink:0;align-items:center;width:108px;height:26px;padding:2px;display:flex}.dn-toggle.light{background:#e5e5e7}.dn-toggle.dark{background:#0a0a0c}.dn-label{text-align:center;letter-spacing:.4px;flex:1;font-size:8.5px;font-weight:700}.dn-toggle.light .dn-label{color:#0a0a0c}.dn-toggle.dark .dn-label{color:#fff}.dn-thumb{color:#0a0a0c;background:#fff;border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;width:22px;height:22px;display:flex}.lang-switch button{border:1px solid var(--border);color:var(--text);cursor:pointer;background:0 0;border-radius:8px;padding:6px 14px;font-size:12px}.lang-switch button.active{border-color:var(--text-h);color:var(--text-h)}.setup-screen{text-align:center;flex-direction:column;flex:1;align-items:center;padding:40px 24px 48px;display:flex}h1{letter-spacing:-.2px;margin:0 0 10px;font-size:22px;font-weight:600}.subtitle{color:var(--text);max-width:340px;margin-bottom:32px;font-size:14px}.gender-select{gap:8px;margin-bottom:28px;display:flex}.gender-select button{border:1px solid var(--border);color:var(--text);cursor:pointer;background:0 0;border-radius:8px;padding:8px 16px;font-size:13px;transition:border-color .15s,color .15s}.gender-select button.active{border-color:var(--text-h);color:var(--text-h)}.avatar-preview{margin-bottom:28px}.mic-test{flex-direction:column;align-items:center;width:100%;max-width:340px;margin-bottom:28px;display:flex}.mic-test-panel{border:1px solid var(--border);box-sizing:border-box;border-radius:12px;width:100%;padding:16px}.mic-hint{color:var(--text);margin:12px 0;font-size:12px}.mic-error{color:#ef4444;margin-top:10px;font-size:12px}.mic-enable-btn{border:1px solid var(--border);color:var(--text-h);cursor:pointer;background:0 0;border-radius:8px;margin-top:12px;padding:8px 16px;font-size:12px}.voice-settings{flex-direction:column;gap:14px;width:100%;max-width:340px;margin-bottom:28px;display:flex}.setting-row{flex-direction:column;gap:8px;display:flex}.setting-label{color:var(--text);font-size:12px}.level-select,.speed-select{flex-wrap:wrap;gap:6px;display:flex}.level-select button,.speed-select button{border:1px solid var(--border);color:var(--text);cursor:pointer;background:0 0;border-radius:8px;padding:6px 12px;font-size:12px;transition:border-color .15s,color .15s}.level-select button.active,.speed-select button.active{border-color:var(--text-h);color:var(--text-h)}.volume-slider{width:100%;accent-color:var(--text-h)}.topic-select{border:1px solid var(--border);width:100%;max-width:340px;color:var(--text-h);box-sizing:border-box;background:0 0;border-radius:10px;margin-bottom:12px;padding:11px 14px;font-family:inherit;font-size:13px}.topic-select:focus{border-color:var(--text-h);outline:none}.topic-select{--lightningcss-light:initial;--lightningcss-dark: ;color-scheme:light}.topic-select option,.topic-select optgroup{color:#0a0a0c;background-color:#fff}.topic-input{border:1px solid var(--border);width:100%;max-width:340px;min-height:84px;color:var(--text-h);resize:vertical;box-sizing:border-box;background:0 0;border-radius:12px;margin-bottom:20px;padding:14px;font-family:inherit;font-size:15px}.topic-input::placeholder{color:var(--text);opacity:.6}.topic-input:focus{border-color:var(--text-h);outline:none}.email-input{border:1px solid var(--border);width:100%;max-width:340px;color:var(--text-h);box-sizing:border-box;background:0 0;border-radius:10px;margin-bottom:20px;padding:12px 14px;font-family:inherit;font-size:14px}.email-input::placeholder{color:var(--text);opacity:.6}.email-input:focus{border-color:var(--text-h);outline:none}.start-btn{border:1px solid var(--text-h);background:var(--text-h);color:var(--bg);cursor:pointer;border-radius:10px;padding:12px 30px;font-size:14px;font-weight:600}.start-btn:disabled{opacity:.35;cursor:not-allowed}.warn{color:#d97706;max-width:320px;margin-top:16px;font-size:12px}.waveform{justify-content:center;align-items:center;gap:3px;width:100%;height:40px;display:flex}.waveform-bar{background:var(--text-h);opacity:.85;border-radius:2px;width:3px;min-height:3px;transition:height 60ms linear}.avatar-wrap{justify-content:center;align-items:center;width:148px;height:148px;display:flex;position:relative}.avatar-photo{background:var(--code-bg);z-index:2;border-radius:50%;justify-content:center;align-items:center;width:128px;height:128px;transition:transform 80ms ease-out,filter 80ms ease-out;display:flex;overflow:hidden}.avatar-photo img{object-fit:cover;width:100%;height:100%}.avatar-placeholder-icon{width:56%;height:56%;fill:var(--border)}.avatar-ring{border:1px solid var(--border);opacity:0;border-radius:50%;transition:opacity .2s;position:absolute;inset:6px}.avatar-wrap.speaking .pulse-ring{opacity:1;border-color:var(--text-h);animation:1.4s ease-out infinite avatarPulse}.listen-ring{border:1px solid var(--text-h);opacity:1;animation:1.1s ease-out infinite avatarPulse;inset:0}@keyframes avatarPulse{0%{opacity:.7;transform:scale(.94)}to{opacity:0;transform:scale(1.18)}}.chat-screen{flex-direction:column;height:100svh;display:flex;overflow:hidden}.chat-header{border-bottom:1px solid var(--border);flex-shrink:0;justify-content:space-between;align-items:center;gap:10px;padding:14px 20px;display:flex}.back-btn{color:var(--text);cursor:pointer;background:0 0;border:none;padding:6px 0;font-size:13px}.topic-label{color:var(--text);text-overflow:ellipsis;white-space:nowrap;max-width:42%;font-size:12px;overflow:hidden}.avatar-area{flex-direction:column;flex-shrink:0;align-items:center;padding:20px 0 8px;display:flex}.teacher-name{color:var(--text-h);margin-top:10px;font-size:14px;font-weight:600}.status-text{color:var(--text);min-height:16px;margin-top:2px;font-size:12px}.chat-log{border:1px solid var(--border);box-sizing:border-box;border-radius:14px;flex-direction:column;flex:1;gap:10px;min-height:0;margin:12px 20px;padding:14px;display:flex;overflow-y:auto}.bubble{border-radius:14px;max-width:82%;padding:10px 14px;font-size:14px;line-height:1.45}.bubble.assistant{background:var(--code-bg);color:var(--text-h);align-self:flex-start}.bubble.user{background:var(--text-h);color:var(--bg);align-self:flex-end}.error-banner{color:#ef4444;border:1px solid #ef4444;border-radius:10px;margin:0 20px 10px;padding:10px 14px;font-size:12px}.input-row{border-top:1px solid var(--border);flex-shrink:0;align-items:center;gap:8px;padding:14px 20px;display:flex}.input-row input{border:1px solid var(--border);color:var(--text-h);background:0 0;border-radius:10px;flex:1;min-width:0;padding:11px 14px;font-size:14px}.input-row input:focus{border-color:var(--text-h);outline:none}.recording-box{border:1px solid var(--text-h);border-radius:10px;flex-direction:column;flex:1;align-items:center;min-width:0;padding:8px 14px;display:flex}.recording-top{align-items:center;gap:10px;width:100%;display:flex}.recording-top .waveform{flex:1}.recording-timer{color:var(--text);font-variant-numeric:tabular-nums;flex-shrink:0;font-family:ui-monospace,SF Mono,Consolas,monospace;font-size:11px}.recording-hint{color:var(--text);margin-top:4px;font-size:11px}.mic-btn,.send-btn{border:1px solid var(--border);cursor:pointer;height:40px;color:var(--text-h);background:0 0;border-radius:10px;flex-shrink:0;justify-content:center;align-items:center;font-size:15px;display:flex}.mic-btn{width:40px}.mic-btn.listening{color:#ef4444;border-color:#ef4444}.mic-stop-square{background:currentColor;border-radius:2px;width:12px;height:12px}.send-btn{width:auto;padding:0 18px;font-size:13px;font-weight:600}.send-btn:disabled{opacity:.35;cursor:not-allowed}