:root{--text:#374151;--text-h:#111827;--bg:#f9fafb;--surface:#fff;--border:#e5e7eb;--primary:#2563eb;--primary-hover:#1d4ed8;--nudge-bg:#f0f9ff;--nudge-border:#bae6fd;--user-bg:#eff6ff;--ai-bg:#fff;--sans:system-ui, -apple-system, sans-serif;--mono:ui-monospace, Consolas, monospace}*{box-sizing:border-box;margin:0;padding:0}body{font:16px/1.5 var(--sans);color:var(--text);background:var(--bg)}#root{flex-direction:column;max-width:800px;min-height:100vh;margin:0 auto;display:flex}.login-container{flex-direction:column;justify-content:center;align-items:center;min-height:100vh;padding:20px;display:flex}.login-card{background:var(--surface);border:1px solid var(--border);border-radius:12px;width:100%;max-width:420px;padding:40px}.login-card h1{color:var(--text-h);margin-bottom:8px;font-size:24px}.login-card p{color:var(--text);margin-bottom:24px;font-size:14px}.login-card input{border:1px solid var(--border);width:100%;font-size:16px;font-family:var(--mono);letter-spacing:1px;border-radius:8px;margin-bottom:16px;padding:12px 16px}.login-card input:focus{outline:2px solid var(--primary);border-color:#0000}.login-card button{background:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:8px;width:100%;padding:12px;font-size:16px}.login-card button:hover{background:var(--primary-hover)}.login-card button:disabled{opacity:.5;cursor:not-allowed}.login-error{color:#dc2626;margin-bottom:12px;font-size:14px}.chat-container{flex-direction:column;min-height:100vh;display:flex}.chat-header{background:var(--surface);border-bottom:1px solid var(--border);z-index:10;justify-content:space-between;align-items:center;padding:12px 20px;display:flex;position:sticky;top:0}.chat-header h2{color:var(--text-h);font-size:16px}.session-info{color:var(--text);font-size:13px;font-family:var(--mono)}.chat-messages{flex-direction:column;flex:1;gap:16px;padding:20px;display:flex;overflow-y:auto}.message{white-space:pre-wrap;border-radius:12px;max-width:85%;padding:12px 16px;font-size:15px;line-height:1.6}.message.user{background:var(--user-bg);color:var(--text-h);border:1px solid #dbeafe;align-self:flex-end}.message.assistant{background:var(--ai-bg);border:1px solid var(--border);color:var(--text);align-self:flex-start}.message .nudge{border-top:1px solid var(--nudge-border);background:var(--nudge-bg);color:#0369a1;border-radius:0 0 12px 12px;margin:12px -16px -12px;padding:12px 16px;font-size:14px;font-style:italic;display:block}.message.system{color:var(--text);background:0 0;border:none;align-self:center;font-size:13px;font-style:italic}.typing-indicator{color:var(--text);align-self:flex-start;padding:12px 16px;font-size:14px;font-style:italic}.chat-input-container{background:var(--surface);border-top:1px solid var(--border);padding:16px 20px;position:sticky;bottom:0}.chat-input-form{gap:8px;display:flex}.chat-input-form textarea{border:1px solid var(--border);font-size:15px;font-family:var(--sans);resize:none;border-radius:8px;flex:1;min-height:48px;max-height:120px;padding:12px 16px}.chat-input-form textarea:focus{outline:2px solid var(--primary);border-color:#0000}.chat-input-form button{background:var(--primary);color:#fff;cursor:pointer;border:none;border-radius:8px;align-self:flex-end;padding:12px 20px;font-size:15px}.chat-input-form button:hover{background:var(--primary-hover)}.chat-input-form button:disabled{opacity:.5;cursor:not-allowed}.turn-count{text-align:center;color:var(--text);margin-top:8px;font-size:12px}