*{box-sizing:border-box}
body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Inter,sans-serif;background:#fff;color:#111}
button,select,textarea{font-family:inherit}
.app{display:flex;min-height:100vh}
.sidebar{width:280px;flex-shrink:0;background:#fff;border-right:1px solid #ececec;padding:20px 16px;display:flex;flex-direction:column;gap:20px;position:sticky;top:0;height:100vh}
.side-logo{font-weight:800;font-size:20px}
.spark{color:#111}
.btn-black{background:#111;color:#fff;border:0;border-radius:999px;padding:12px 14px;font-weight:700;font-size:15px;cursor:pointer;text-align:left}
.side-label{font-size:12px;letter-spacing:.06em;text-transform:uppercase;color:#999;display:block;margin-bottom:8px}
.chat-list{display:flex;flex-direction:column;gap:6px}
.chat-item{background:#f5f5f5;border-radius:10px;padding:10px 12px;font-size:13px;color:#666;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}
.side-note{color:#999;font-size:13px;line-height:1.6}
.side-bottom{margin-top:auto}
.main{flex:1;min-width:0;display:flex;flex-direction:column}
.topbar{display:flex;align-items:center;gap:12px;padding:14px 20px}
.circle-btn{width:46px;height:46px;flex-shrink:0;border:1px solid #e5e5e5;border-radius:50%;background:#fff;color:#111;font-size:20px;cursor:pointer}
.circle-btn.small{width:38px;height:38px;font-size:22px}
.tabs{display:flex;gap:26px;margin:0 auto}
.tab{background:none;border:0;font-size:19px;color:#b3b3b3;font-weight:600;cursor:pointer;padding:6px 2px 10px;position:relative}
.tab.active{color:#111}
.tab.active::after{content:"";position:absolute;left:20%;right:20%;bottom:0;height:3px;border-radius:3px;background:#111}
.top-spacer{width:46px;flex-shrink:0}
.chat-wrap{flex:1;width:100%;max-width:860px;margin:0 auto;padding:16px 20px}
.status{padding:12px 14px;border-radius:12px;background:#fef3c7;margin-bottom:16px;display:none;line-height:1.5;font-size:14px}
.status.show{display:block}
.hero-logo{text-align:center;font-size:190px;line-height:1;color:#ececec;margin-top:12vh;user-select:none}
.msg-row{display:flex;gap:10px;margin-bottom:18px;align-items:flex-start}
.msg-row.user{flex-direction:row-reverse}
.avatar{width:32px;height:32px;flex-shrink:0;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:14px;color:#999}
.avatar.user{background:#f0f0f0;color:#111;font-size:11px;font-weight:700}
.msg{max-width:82%;padding:13px 16px;border-radius:20px;line-height:1.65;white-space:pre-wrap;word-wrap:break-word;font-size:15px}
.msg-row.ai .msg{background:transparent;padding:13px 2px;max-width:100%}
.msg-row.user .msg{background:#f0f0f0;color:#111}
.msg pre{background:#f7f7f7;border:1px solid #eee;padding:10px;border-radius:10px;overflow:auto;white-space:pre}
.msg code{font-family:ui-monospace,monospace;font-size:13px}
.copy-btn{margin-top:6px;background:#fff;color:#999;border:1px solid #e5e5e5;border-radius:999px;padding:5px 11px;font-size:12px;cursor:pointer}
.typing{display:flex;gap:6px;padding:10px 0 10px 42px}
.typing span{width:8px;height:8px;border-radius:50%;background:#bbb;animation:blink 1.2s infinite}
.typing span:nth-child(2){animation-delay:.2s}.typing span:nth-child(3){animation-delay:.4s}
@keyframes blink{0%,100%{opacity:.3}50%{opacity:1}}
.hidden{display:none}
.bottom{position:sticky;bottom:0;background:#fff;padding:8px 20px 12px}
.suggest-row{display:flex;gap:10px;overflow-x:auto;padding:4px 2px 12px;max-width:860px;margin:0 auto;scrollbar-width:none}
.suggest-row::-webkit-scrollbar{display:none}
.suggest-pill{flex-shrink:0;background:#fff;border:1px solid #e5e5e5;border-radius:999px;padding:10px 16px;font-size:14px;cursor:pointer;white-space:nowrap}
.suggest-pill:hover{border-color:#111}
.composer{max-width:860px;margin:0 auto;background:#fff;border:1px solid #e5e5e5;border-radius:28px;padding:14px 14px 10px;box-shadow:0 10px 30px rgba(0,0,0,.08)}
.composer textarea{width:100%;background:transparent;border:0;color:#111;font-size:17px;resize:none;max-height:140px;outline:none;padding:4px 6px}
.composer-row{display:flex;align-items:center;gap:8px;margin-top:6px}
.fast-wrap{display:flex;align-items:center;gap:4px;background:#f5f5f5;border-radius:999px;padding:6px 12px;font-size:14px}
.fast-wrap select{background:transparent;border:0;outline:none;font-size:14px;font-weight:600;max-width:170px}
.flex{flex:1}
.speak-btn{background:#111;color:#fff;border:0;border-radius:999px;padding:10px 16px;font-size:14px;font-weight:700;cursor:pointer}
.send-btn{width:42px;height:42px;flex-shrink:0;border:0;border-radius:50%;background:#111;color:#fff;font-size:20px;cursor:pointer}
.send-btn:disabled{opacity:.4}
.small{max-width:860px;margin:10px auto 0;color:#bbb;font-size:12px;text-align:center}
.overlay{display:none}
@media(max-width:820px){
  .sidebar{position:fixed;left:-300px;top:0;z-index:20;transition:left .2s;box-shadow:0 0 40px rgba(0,0,0,.15)}
  .sidebar.open{left:0}
  .overlay.show{display:block;position:fixed;inset:0;background:rgba(0,0,0,.4);z-index:15}
  .topbar{padding:10px 14px}
  .tabs{gap:16px}.tab{font-size:17px}
  .top-spacer{display:none}
  .hero-logo{font-size:130px}
  .msg{max-width:88%}
  .chat-wrap{padding:12px 14px}
  .bottom{padding:8px 12px 10px}
  .fast-wrap select{max-width:110px}
  .speak-btn{padding:9px 12px}
}