:root{color-scheme:light;--bg:#edf2f5;--panel:#ffffff;--ink:#191715;--muted:#6c665f;--line:#d8dee5;--accent:#176b5d;--accent-strong:#0d4d42;--danger:#a23b3b;--assistant:#eef6f2;--user:#ffe9dd}*{box-sizing:border-box}body{margin:0;min-height:100vh;background:var(--bg);color:var(--ink);font-family:Arial,Helvetica,sans-serif}button,textarea{font:inherit}.shell{min-height:100vh;padding:24px;display:grid;place-items:center}.workspace{width:min(980px,100%);height:min(820px,calc(100vh - 48px));min-height:560px;display:grid;grid-template-rows:auto 1fr auto auto;background:var(--panel);border:1px solid var(--line);border-radius:8px;overflow:hidden;box-shadow:0 18px 60px rgba(28,36,44,.14)}.topbar{padding:18px 20px;display:flex;align-items:center;justify-content:space-between;gap:16px;border-bottom:1px solid var(--line)}.eyebrow{margin:0 0 4px;color:var(--accent);font-size:13px;font-weight:700;text-transform:uppercase}h1{margin:0;font-size:clamp(24px,4vw,34px);line-height:1.1;letter-spacing:0}.status{flex:0 0 auto;padding:8px 12px;border:1px solid #a9c9be;border-radius:999px;color:var(--accent-strong);background:#e5f3ee;font-size:14px;font-weight:700}.messages{padding:20px;overflow-y:auto;display:flex;flex-direction:column;gap:14px}.message{display:grid;grid-template-columns:40px minmax(0,1fr);grid-gap:12px;gap:12px;align-items:start;max-width:780px}.message.user{align-self:end}.message p{margin:0;padding:13px 15px;border-radius:8px;line-height:1.5;white-space:pre-wrap;overflow-wrap:anywhere}.message.assistant p{background:var(--assistant);border:1px solid #d4e8df}.message.user p{background:var(--user);border:1px solid #edd0ad}.avatar{width:40px;height:40px;display:grid;place-items:center;border-radius:8px;background:var(--ink);color:white;font-size:13px;font-weight:800}.error{margin:0 20px 12px;padding:11px 13px;border:1px solid #e7b3b3;border-radius:8px;background:#fff1f1;color:var(--danger)}.composer{padding:16px;display:grid;grid-template-columns:1fr auto;grid-gap:12px;gap:12px;border-top:1px solid var(--line);background:#f7f9fb}textarea{width:100%;min-height:72px;resize:vertical;padding:13px 14px;border:1px solid var(--line);border-radius:8px;background:white;color:var(--ink);outline:none}textarea:focus{border-color:var(--accent);box-shadow:0 0 0 3px rgba(23,107,93,.18)}button{align-self:end;min-width:104px;min-height:48px;border:0;border-radius:8px;background:var(--accent);color:white;font-weight:800;cursor:pointer}button:disabled{cursor:not-allowed;opacity:.48}button:not(:disabled):hover{background:var(--accent-strong)}@media (max-width:680px){.shell{padding:0}.workspace{height:100vh;min-height:100vh;border:0;border-radius:0}.topbar{align-items:flex-start;flex-direction:column}.composer{grid-template-columns:1fr}button{width:100%}}