:root{--bg: #ffffff;--bg-soft: #f6f7f9;--sidebar: #f0f2f5;--border: #e3e6ea;--text: #1c1f24;--muted: #6b7280;--accent: #4f46e5;--accent-text: #ffffff;--user-bubble: #eef0ff;--code-bg: #f3f4f6;--error: #b91c1c;font-family:Inter,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;color:var(--text);background:var(--bg)}@media(prefers-color-scheme:dark){:root{--bg: #17181c;--bg-soft: #1f2126;--sidebar: #111215;--border: #2c2f36;--text: #e6e7ea;--muted: #9097a3;--accent: #818cf8;--accent-text: #0b0c10;--user-bubble: #262a3d;--code-bg: #24262c;--error: #f87171}}*{box-sizing:border-box}body{margin:0}button{font:inherit;cursor:pointer}.app{display:flex;height:100vh}.sidebar{width:260px;flex-shrink:0;display:flex;flex-direction:column;background:var(--sidebar);border-right:1px solid var(--border);padding:12px;gap:12px}.new-chat{padding:10px 12px;border:1px solid var(--border);border-radius:10px;background:var(--bg);color:var(--text);text-align:left;font-weight:500}.new-chat:hover{border-color:var(--accent)}.history{flex:1;overflow-y:auto;display:flex;flex-direction:column;gap:2px}.history-item{display:flex;align-items:center;padding:8px 10px;border-radius:8px;cursor:pointer;font-size:14px}.history-item:hover,.history-item.active{background:var(--bg-soft)}.history-title{flex:1;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.history-delete{visibility:hidden;border:none;background:none;color:var(--muted);font-size:16px;line-height:1}.history-item:hover .history-delete{visibility:visible}.sidebar-footer{font-size:12px;color:var(--muted)}.main{flex:1;display:flex;flex-direction:column;min-width:0}.topbar{display:flex;align-items:center;gap:12px;padding:10px 20px;border-bottom:1px solid var(--border)}.model-select{padding:6px 10px;border-radius:8px;border:1px solid var(--border);background:var(--bg);color:var(--text);font:inherit;font-size:14px}.topbar-error{color:var(--error);font-size:13px}.thread{flex:1;overflow-y:auto}.welcome{max-width:720px;margin:18vh auto 0;padding:0 20px;text-align:center}.welcome h1{font-weight:600;font-size:28px;margin-bottom:28px}.suggestions{display:grid;grid-template-columns:1fr 1fr;gap:10px}.suggestion{padding:14px;border:1px solid var(--border);border-radius:12px;background:var(--bg-soft);color:var(--text);text-align:left;font-size:14px}.suggestion:hover{border-color:var(--accent)}.messages{max-width:820px;margin:0 auto;padding:24px 20px 8px;display:flex;flex-direction:column;gap:22px}.message{display:flex;gap:12px}.avatar{flex-shrink:0;width:32px;height:32px;border-radius:50%;display:grid;place-items:center;font-size:11px;font-weight:600;background:var(--bg-soft);border:1px solid var(--border)}.message-assistant .avatar{background:var(--accent);color:var(--accent-text);border:none}.message-body{flex:1;min-width:0;line-height:1.6}.user-text{display:inline-block;white-space:pre-wrap;background:var(--user-bubble);padding:8px 14px;border-radius:14px}.markdown>:first-child{margin-top:4px}.markdown pre{background:var(--code-bg);padding:12px 14px;border-radius:10px;overflow-x:auto}.markdown code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.9em}.markdown :not(pre)>code{background:var(--code-bg);padding:2px 5px;border-radius:5px}.markdown table{border-collapse:collapse}.markdown th,.markdown td{border:1px solid var(--border);padding:6px 10px}.markdown a{color:var(--accent)}.cursor{display:inline-block;width:8px;height:1em;margin-left:2px;vertical-align:text-bottom;background:var(--text);animation:blink 1s steps(2) infinite}@keyframes blink{to{visibility:hidden}}.reasoning{margin-bottom:8px;font-size:13px;color:var(--muted)}.reasoning summary{cursor:pointer}.reasoning-text{white-space:pre-wrap;border-left:2px solid var(--border);padding:4px 0 4px 10px;margin-top:6px;max-height:240px;overflow-y:auto}.message-error{color:var(--error);font-size:14px;margin-top:6px}.message-meta{display:flex;gap:12px;margin-top:6px;font-size:12px;color:var(--muted)}.link-button{border:none;background:none;padding:0;color:var(--muted);font-size:12px}.link-button:hover{color:var(--text)}.composer{padding:12px 20px 16px}.composer-box{max-width:820px;margin:0 auto;display:flex;align-items:flex-end;gap:8px;border:1px solid var(--border);border-radius:14px;padding:8px 8px 8px 14px;background:var(--bg-soft)}.composer-box:focus-within{border-color:var(--accent)}.composer textarea{flex:1;resize:none;border:none;outline:none;background:transparent;color:var(--text);font:inherit;max-height:200px;field-sizing:content;padding:6px 0}.send{padding:8px 16px;border:none;border-radius:10px;background:var(--accent);color:var(--accent-text);font-weight:500}.send:disabled{opacity:.4;cursor:default}.send.stop{background:var(--text);color:var(--bg)}.disclaimer{text-align:center;font-size:12px;color:var(--muted);margin-top:8px}@media(max-width:720px){.sidebar{display:none}.suggestions{grid-template-columns:1fr}}