:root{--bg:#0b1020;--panel:#11182d;--muted:#8ea0c7;--text:#f4f7ff;--line:#24304f;--accent:#6d7cff;--accent2:#0f172a;}*{box-sizing:border-box}body{margin:0;font-family:Inter,ui-sans-serif,system-ui,sans-serif;background:linear-gradient(180deg,#0a0f1d,#11182d);color:var(--text)}.hidden{display:none!important}.shell{min-height:100vh;padding:24px}.auth-shell,.chat-shell{min-height:calc(100vh - 48px);display:flex;align-items:center;justify-content:center}.auth-card,.chat-card{width:min(100%,420px);background:rgba(17,24,45,.92);border:1px solid var(--line);border-radius:20px;box-shadow:0 30px 80px rgba(0,0,0,.35)}.auth-card{padding:28px}.badge{display:inline-block;padding:6px 10px;border-radius:999px;background:#1b2650;color:#b9c6ff;font-size:12px;font-weight:700;margin-bottom:16px}.auth-card h1{margin:0 0 10px;font-size:32px}.subtle{color:var(--muted);margin:0 0 18px}form{display:flex;gap:10px;flex-direction:column}input{width:100%;padding:14px 16px;border-radius:14px;border:1px solid var(--line);background:#0b1020;color:var(--text);font-size:15px}button,.button{padding:14px 16px;border-radius:14px;border:0;background:var(--accent);color:#fff;font-weight:700;font-size:15px;cursor:pointer;text-decoration:none}.button.secondary,.link-button{background:transparent;border:1px solid var(--line);color:var(--muted)}.notice{margin-top:16px;padding:14px;border:1px solid var(--line);border-radius:14px;background:#0b1020;color:var(--muted)}.chat-card{width:min(100%,840px);height:min(88vh,760px);display:flex;flex-direction:column;overflow:hidden}.chat-head{display:flex;justify-content:space-between;align-items:center;padding:18px 20px;border-bottom:1px solid var(--line)}.chat-title{font-size:20px;font-weight:800}.chat-subtitle{font-size:13px;color:var(--muted);margin-top:4px}.messages{flex:1;padding:20px;overflow:auto;background:rgba(8,12,24,.55)}.msg{display:flex;margin:0 0 14px}.msg.user{justify-content:flex-end}.bubble{max-width:min(80%,680px);padding:12px 14px;border-radius:16px;white-space:pre-wrap;line-height:1.45}.msg.assistant .bubble{background:#161f3c;border:1px solid var(--line)}.msg.user .bubble{background:var(--accent);color:#fff}.chat-form{display:flex;gap:10px;padding:16px;border-top:1px solid var(--line);flex-direction:row}.chat-form input{flex:1}.chat-form button{min-width:110px}.link-button{padding:10px 12px}@media (max-width:720px){.shell{padding:0}.auth-shell,.chat-shell{min-height:100vh}.auth-card,.chat-card{width:100%;min-height:100vh;border-radius:0;border:0}.chat-card{height:100vh}}