body{background:var(--c-bg-alt)}.chat-app{max-width:560px;margin:0 auto;min-height:100dvh;display:flex;flex-direction:column}.chat-header{position:sticky;top:0;z-index:10;background:#fff;border-bottom:1.5px solid var(--c-line);padding:10px 16px 12px}.chat-header .badges{display:flex;justify-content:space-between;align-items:center;font-size:12.5px;color:var(--c-text-sub);margin-bottom:8px}.chat-header .badges .left{font-weight:700;color:var(--c-main-dark)}.progress-track{background:var(--c-bg-alt);border-radius:999px;height:8px;overflow:hidden}.progress-fill{height:100%;background:var(--c-main);border-radius:999px;width:0%;transition:width .4s ease}.chat-log{flex:1;padding:20px 16px 8px;overflow-y:auto}.msg{display:flex;margin-bottom:14px;animation:pop-in .3s ease}@keyframes pop-in{0%{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}.msg.bot{align-items:flex-end;gap:8px}.msg.bot .avatar{width:44px;height:44px;flex-shrink:0;background:#fff;border:1.5px solid var(--c-line);border-radius:50%;display:flex;align-items:center;justify-content:center;overflow:hidden}.msg.bot .avatar img{width:38px;height:38px;object-fit:contain}.msg .bubble{max-width:78%;padding:12px 16px;border-radius:var(--radius-lg);font-size:15px;background:#fff;border:1.5px solid var(--c-line);border-bottom-left-radius:6px;box-shadow:var(--shadow)}.msg.user{justify-content:flex-end}.msg.user .bubble{background:var(--c-main);color:#fff;border:none;border-bottom-left-radius:var(--radius-lg);border-bottom-right-radius:6px}.msg.interstitial{justify-content:center}.msg.interstitial .bubble{background:var(--c-main-pale);border-color:transparent;color:var(--c-main-dark);font-size:13.5px;border-radius:var(--radius);text-align:center}.answer-area{position:sticky;bottom:0;background:linear-gradient(to top,var(--c-bg-alt) 82%,transparent);padding:8px 16px 18px}.back-row{margin-bottom:8px;min-height:22px}.back-btn{background:none;border:none;color:var(--c-text-sub);font-size:12.5px;text-decoration:underline;padding:2px 4px}.options{display:flex;flex-wrap:wrap;gap:8px}.opt-btn{background:#fff;border:1.5px solid var(--c-main);color:var(--c-main-dark);border-radius:999px;padding:10px 18px;font-size:14.5px;transition:background .15s ease,color .15s ease,transform .1s ease}.opt-btn:hover{background:var(--c-main-pale)}.opt-btn:active{transform:scale(.97)}.opt-btn.selected{background:var(--c-main);color:#fff}.done-btn{width:100%;margin-top:10px;background:var(--c-accent);color:#fff;border:none;border-radius:999px;padding:14px;font-family:var(--font-head);font-size:16px;font-weight:700;box-shadow:0 4px 14px #ff8a5c59}.done-btn:disabled{background:#cfd8d4;box-shadow:none}.thinking{display:inline-flex;gap:4px;align-items:center}.thinking span{width:7px;height:7px;border-radius:50%;background:var(--c-main);animation:bounce 1s infinite ease-in-out}.thinking span:nth-child(2){animation-delay:.15s}.thinking span:nth-child(3){animation-delay:.3s}@keyframes bounce{0%,60%,to{transform:translateY(0)}30%{transform:translateY(-5px)}}.error-note{color:var(--c-bad);font-size:13px;margin-top:6px}.retry-btn{margin-top:8px;background:var(--c-main);color:#fff;border:none;border-radius:999px;padding:10px 24px;font-size:14px}