:root{--bg: #f2f7f5;--panel: #ffffff;--text: #1c2b27;--text-dim: #6a807a;--border: #dce8e4;--user-bubble: #12a394;--user-text: #ffffff;--ai-bubble: #ffffff;--error: #d70015;--code-bg: #eef4f2}@media(prefers-color-scheme:dark){:root{--bg: #14201d;--panel: #1d2c28;--text: #eaf3f0;--text-dim: #8ea69f;--border: #2b3d38;--user-bubble: #17b3a2;--user-text: #ffffff;--ai-bubble: #1d2c28;--error: #ff453a;--code-bg: #14201d}}*{box-sizing:border-box;margin:0;padding:0}html,body,#root{height:100%}body{font-family:-apple-system,BlinkMacSystemFont,PingFang SC,Segoe UI,Microsoft YaHei,sans-serif;background:var(--bg);color:var(--text);-webkit-font-smoothing:antialiased}.app{display:flex;flex-direction:column;height:100%;max-width:760px;margin:0 auto}.header{display:flex;align-items:center;justify-content:space-between;padding:12px 16px;border-bottom:1px solid var(--border);background:var(--bg)}.brand{display:flex;align-items:center;gap:10px}.avatar{width:36px;height:36px;border-radius:50%;object-fit:cover;border:2px solid rgba(18,163,148,.2);box-shadow:0 0 0 1px var(--border)}.header h1{font-size:17px;font-weight:600;display:flex;align-items:baseline;gap:8px;margin:0}.header h1 .sub{font-size:12px;font-weight:500;color:var(--text-dim)}.clear-btn{border:1px solid var(--border);background:transparent;color:var(--text-dim);font-size:13px;padding:4px 12px;border-radius:14px;cursor:pointer}.clear-btn:hover{color:var(--error);border-color:var(--error)}.message-list{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:12px}.empty-hint{margin:auto;text-align:center;color:var(--text-dim);display:flex;flex-direction:column;align-items:center}.empty-avatar{width:72px;height:72px;border-radius:50%;object-fit:cover;margin-bottom:12px;border:3px solid rgba(18,163,148,.18);box-shadow:0 4px 14px #12a3942e}.empty-hint p:first-of-type{font-size:20px;color:var(--text);margin-bottom:8px}.empty-sub{font-size:13px}.msg{display:flex;align-items:flex-end;gap:8px}.msg-user{justify-content:flex-end}.msg-ai{justify-content:flex-start}.msg-avatar{width:32px;height:32px;border-radius:50%;object-fit:cover;flex-shrink:0;border:1px solid var(--border)}.msg-bubble{max-width:85%;padding:10px 14px;border-radius:18px;font-size:15px;line-height:1.6;word-break:break-word}.msg-user .msg-bubble{background:var(--user-bubble);color:var(--user-text);border-bottom-right-radius:4px}.msg-ai .msg-bubble{background:var(--ai-bubble);border:1px solid var(--border);border-bottom-left-radius:4px}.msg-error .msg-bubble{color:var(--error);border-color:var(--error)}.msg-text{white-space:pre-wrap}.msg-md>*:not(:last-child){margin-bottom:.6em}.msg-md h1,.msg-md h2,.msg-md h3{font-size:1.05em}.msg-md ul,.msg-md ol{padding-left:1.4em}.msg-md pre{background:var(--code-bg);border:1px solid var(--border);border-radius:8px;padding:10px 12px;overflow-x:auto;font-size:13px}.msg-md code{font-family:ui-monospace,SF Mono,Menlo,Consolas,monospace;background:var(--code-bg);border-radius:4px;padding:1px 5px;font-size:.9em}.msg-md pre code{background:none;padding:0}.msg-md table{border-collapse:collapse;font-size:14px}.msg-md th,.msg-md td{border:1px solid var(--border);padding:4px 10px}.msg-md blockquote{border-left:3px solid var(--border);padding-left:10px;color:var(--text-dim)}.msg-md a{color:var(--user-bubble)}.cursor{display:inline-block;width:2px;height:1em;background:var(--text);vertical-align:text-bottom;margin-left:2px;animation:blink .9s steps(1) infinite}@keyframes blink{50%{opacity:0}}.dots{display:inline-flex;gap:4px;padding:4px 0}.dots i{width:7px;height:7px;border-radius:50%;background:var(--text-dim);animation:bounce 1.2s ease-in-out infinite}.dots i:nth-child(2){animation-delay:.15s}.dots i:nth-child(3){animation-delay:.3s}@keyframes bounce{0%,60%,to{transform:translateY(0);opacity:.5}30%{transform:translateY(-5px);opacity:1}}.chat-input{display:flex;align-items:flex-end;gap:8px;padding:12px 16px calc(12px + env(safe-area-inset-bottom));border-top:1px solid var(--border);background:var(--bg)}.chat-input textarea{flex:1;resize:none;border:1px solid var(--border);border-radius:20px;padding:10px 16px;font-size:15px;font-family:inherit;line-height:1.5;background:var(--panel);color:var(--text);outline:none;max-height:160px}.chat-input textarea:focus{border-color:var(--user-bubble)}.chat-input button{width:40px;height:40px;border:none;border-radius:50%;background:var(--user-bubble);color:#fff;font-size:16px;cursor:pointer;flex-shrink:0}.chat-input button:disabled{opacity:.4;cursor:default}@media(max-width:480px){.msg-bubble{max-width:92%}}