:root{--bg:#0f1115;--panel:#161a22;--panel-2:#1d222c;--border:#272d39;--text:#e7eaf0;--muted:#9aa3b2;--accent:#4f8cff;--accent-2:#2f6bd6;--user:#243044;--danger:#ff6b6b}*{box-sizing:border-box}body,html{margin:0;padding:0;height:100%;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif;font-size:15px}button{font-family:inherit;cursor:pointer}.login-wrap{height:100vh;display:grid;place-items:center}.login-card{width:340px;background:var(--panel);border:1px solid var(--border);border-radius:14px;padding:28px}.login-card h1{margin:0 0 4px;font-size:20px}.login-card p{margin:0 0 20px;color:var(--muted);font-size:13px}.field{width:100%;padding:11px 12px;background:var(--panel-2);border:1px solid var(--border);border-radius:9px;color:var(--text);font-size:14px;outline:none}.field:focus{border-color:var(--accent)}.btn{width:100%;margin-top:12px;padding:11px 12px;background:var(--accent);border:none;border-radius:9px;color:white;font-weight:600;font-size:14px}.btn:hover{background:var(--accent-2)}.btn:disabled{opacity:.6;cursor:default}.error{color:var(--danger);font-size:13px;margin-top:10px}.app{display:grid;grid-template-columns:280px 1fr;height:100vh}.sidebar{background:var(--panel);border-right:1px solid var(--border);display:flex;flex-direction:column;min-height:0}.sidebar-head{padding:16px;border-bottom:1px solid var(--border)}.brand{font-weight:700;font-size:15px}.brand small{display:block;color:var(--muted);font-weight:400;font-size:12px}.new-btn{margin-top:14px;width:100%;padding:9px;border-radius:9px;background:var(--accent);color:#fff;border:none;font-weight:600}.new-btn:hover{background:var(--accent-2)}.conv-list{flex:1 1;overflow-y:auto;padding:8px}.conv{display:flex;align-items:center;justify-content:space-between;gap:6px;padding:9px 10px;border-radius:8px;color:var(--text);cursor:pointer;font-size:13.5px}.conv.active,.conv:hover{background:var(--panel-2)}.conv span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.conv .del{opacity:0;background:none;border:none;color:var(--muted);font-size:15px}.conv:hover .del{opacity:1}.conv .del:hover{color:var(--danger)}.sidebar-foot{padding:12px 16px;border-top:1px solid var(--border);display:flex;justify-content:space-between;align-items:center}.link-btn,.sidebar-foot{color:var(--muted);font-size:12px}.link-btn{background:none;border:none}.link-btn:hover{color:var(--text)}.main{display:flex;flex-direction:column;min-width:0;min-height:0}.messages{flex:1 1;overflow-y:auto;padding:28px 0}.empty{height:100%;display:grid;place-items:center;color:var(--muted);text-align:center;padding:0 40px}.row{max-width:760px;margin:0 auto 18px;padding:0 24px;display:flex}.row.user{justify-content:flex-end}.bubble{padding:12px 15px;border-radius:14px;white-space:pre-wrap;word-wrap:break-word;line-height:1.5;max-width:88%}.row.user .bubble{background:var(--user);border-bottom-right-radius:4px}.row.assistant .bubble{background:var(--panel);border:1px solid var(--border);border-bottom-left-radius:4px}.role{font-size:11px;color:var(--muted);margin-bottom:4px}.cursor:after{content:"▋";margin-left:2px;animation:blink 1s steps(2) infinite;color:var(--accent)}@keyframes blink{0%,50%{opacity:1}50.01%,to{opacity:0}}.composer{border-top:1px solid var(--border);padding:14px 24px 20px;background:var(--bg)}.composer-inner{max-width:760px;margin:0 auto;display:flex;gap:10px;align-items:flex-end}.composer textarea{flex:1 1;resize:none;max-height:200px;padding:12px 14px;background:var(--panel);border:1px solid var(--border);border-radius:12px;color:var(--text);font-size:14.5px;line-height:1.4;outline:none}.composer textarea:focus{border-color:var(--accent)}.send{padding:12px 18px;background:var(--accent);border:none;border-radius:12px;color:#fff;font-weight:600;font-size:14px}.send:hover{background:var(--accent-2)}.send:disabled{opacity:.5;cursor:default}.hint{max-width:760px;margin:8px auto 0;color:var(--muted);font-size:11.5px;text-align:center}