:root{color-scheme:light;--page:#f5f5f5;--panel:#fff;--text:#111;--muted:#747474;--line:#e5e5e5;--input:#f7f7f7;--user:#111;--user-text:#fff;--button:#111;--button-text:#fff;--disabled:#ddd}
:root[data-theme="dark"]{color-scheme:dark;--page:#080808;--panel:#121212;--text:#ededed;--muted:#969696;--line:#2c2c2c;--input:#1c1c1c;--user:#ededed;--user-text:#111;--button:#ededed;--button-text:#111;--disabled:#3e3e3e}
@media(prefers-color-scheme:dark){:root:not([data-theme]){color-scheme:dark;--page:#080808;--panel:#121212;--text:#ededed;--muted:#969696;--line:#2c2c2c;--input:#1c1c1c;--user:#ededed;--user-text:#111;--button:#ededed;--button-text:#111;--disabled:#3e3e3e}}
*{box-sizing:border-box}html,body{height:100%;margin:0}body{background:var(--page);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;display:grid;place-items:center;padding:28px;-webkit-font-smoothing:antialiased}button,textarea{font:inherit}button{cursor:pointer;-webkit-tap-highlight-color:transparent}button:disabled{cursor:default}[hidden]{display:none!important}.chat{background:var(--panel);border:1px solid var(--line);border-radius:18px;width:min(860px,100%);height:min(820px,calc(100dvh - 56px));display:flex;flex-direction:column;overflow:hidden}.toolbar{display:flex;justify-content:flex-end;align-items:center;height:52px;flex-shrink:0;padding:8px 12px}.theme{width:34px;height:34px;display:grid;place-items:center;background:none;border:0;border-radius:8px;color:var(--muted)}.theme:hover{background:var(--input);color:var(--text)}.sun{display:none}:root[data-theme="dark"] .sun{display:block}:root[data-theme="dark"] .moon{display:none}.conversation{flex:1;min-height:0;overflow-y:auto;overscroll-behavior:contain;padding:12px 28px 26px;display:flex;flex-direction:column;gap:23px;scrollbar-width:thin;scrollbar-color:var(--line) transparent}.message{display:flex;flex-shrink:0}.message.user{justify-content:flex-end}.bubble{font-size:15px;line-height:1.85;white-space:pre-wrap;overflow-wrap:anywhere;max-width:92%;padding:4px 0}.user .bubble{background:var(--user);color:var(--user-text);padding:10px 16px;border-radius:16px 16px 4px 16px;max-width:85%}.input-area{padding:12px 20px 20px;flex-shrink:0}.composer{display:flex;align-items:flex-end;gap:12px;background:var(--input);border:1px solid var(--line);border-radius:14px;padding:10px 11px 10px 16px}.composer:focus-within{border-color:var(--muted)}textarea{width:100%;resize:none;outline:0;border:0;background:transparent;color:var(--text);min-height:38px;max-height:150px;padding:7px 0;line-height:24px;font-size:15px;scrollbar-width:thin}textarea::placeholder{color:var(--muted)}textarea:disabled{opacity:.6}.send{width:36px;height:36px;flex-shrink:0;display:grid;place-items:center;border:0;border-radius:10px;background:var(--button);color:var(--button-text)}.send:disabled{background:var(--disabled);color:var(--muted)}.spinner{display:none;width:16px;height:16px;border:2px solid currentColor;border-top-color:transparent;border-radius:50%;animation:spin .8s linear infinite}.busy .send-arrow{display:none}.busy .spinner{display:block}.error{font-size:12px;line-height:1.6;color:var(--muted);padding:0 3px 10px}button:focus-visible{outline:2px solid var(--text);outline-offset:3px}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}@keyframes spin{to{transform:rotate(360deg)}}
@media(max-width:600px){body{padding:0}.chat{width:100%;height:100dvh;border:0;border-radius:0}.toolbar{height:48px;padding-right:12px}.conversation{padding:8px 19px 22px;gap:20px}.bubble{font-size:15px;max-width:96%}.user .bubble{max-width:88%}.input-area{padding:10px 12px max(12px,env(safe-area-inset-bottom))}.composer{gap:9px;padding-left:13px}textarea{font-size:16px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;animation:none!important}}