:root{color-scheme:light;--bg:#f7f8fb;--panel:#ffffff;--line:#d7dce5;--ink:#111827;--muted:#64748b;--accent:#0f766e;--accent-strong:#115e59;--danger:#b42318;--soft:#edf7f5}*{box-sizing:border-box}body,html{min-height:100%;margin:0;background:var(--bg);color:var(--ink);font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}button,input,textarea{font:inherit}.shell{min-height:100vh;display:grid;grid-template-rows:auto 1fr auto}.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:16px 24px;border-bottom:1px solid var(--line);background:rgba(255,255,255,.92);position:-webkit-sticky;position:sticky;top:0;z-index:2}.brand{display:grid;grid-gap:2px;gap:2px}.brand strong{font-size:15px}.brand span,.status{color:var(--muted);font-size:13px}.status{display:flex;align-items:center;gap:8px}.status-dot{width:9px;height:9px;border-radius:999px;background:var(--accent)}.messages{width:min(920px,100%);margin:0 auto;padding:28px 18px 128px;display:grid;align-content:start;grid-gap:14px;gap:14px}.message{max-width:78%;padding:12px 14px;border:1px solid var(--line);border-radius:8px;background:var(--panel);white-space:pre-wrap;line-height:1.48;font-size:15px}.message.user{justify-self:end;background:#e8f1ff}.message.assistant{justify-self:start}.message.error{border-color:#f2b8b5;color:var(--danger)}.message-meta{display:block;color:var(--muted);font-size:12px;margin-bottom:6px}.composer{position:fixed;left:0;right:0;bottom:0;border-top:1px solid var(--line);background:rgba(247,248,251,.96);padding:14px 18px}.composer form{width:min(920px,100%);margin:0 auto;display:grid;grid-template-columns:1fr auto;grid-gap:10px;gap:10px}.composer textarea{min-height:54px;max-height:180px;resize:vertical;border:1px solid var(--line);border-radius:8px;padding:14px;background:var(--panel);color:var(--ink)}.composer button{min-width:96px;border:0;border-radius:8px;padding:0 18px;background:var(--accent);color:white;cursor:pointer;font-weight:650}.composer button:disabled{cursor:not-allowed;opacity:.6}.evidence{width:min(920px,100%);margin:0 auto;padding:0 18px 18px;color:var(--muted);font-size:13px}@media (max-width:680px){.topbar{align-items:flex-start;flex-direction:column}.message{max-width:94%}.composer form{grid-template-columns:1fr}.composer button{height:44px}}