:root{--bg:#f5f7fb;--panel:#ffffffcc;--ink:#111827;--muted:#6b7280;--line:#dce3ee;--accent:#1f5eff;--dark:#151a22;--bubble:#fff;--mine:#dfe7f8}
*{box-sizing:border-box}body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:radial-gradient(circle at top left,#eef5ff,#f8fafc 45%,#eef1f7);color:var(--ink)}
.login-wrap{min-height:100vh;display:grid;place-items:center;padding:22px}.login-card{width:min(420px,100%);background:#fff;border:1px solid var(--line);border-radius:28px;padding:28px;box-shadow:0 30px 80px #0002}.brand{display:flex;align-items:center;gap:10px;font-size:22px}.logo,.xmark{display:grid;place-items:center;width:34px;height:34px;border-radius:10px;background:linear-gradient(135deg,#1f5eff,#111827);color:#fff;font-weight:900}.muted{color:var(--muted);font-size:14px}.error{background:#fee2e2;color:#991b1b;border-radius:14px;padding:10px;margin:12px 0}label{display:block;font-weight:600;margin:14px 0 8px}input,select{width:100%;border:1px solid var(--line);border-radius:14px;padding:12px 14px;background:#fff;color:var(--ink);font:inherit}button{font:inherit;border:0;border-radius:14px;padding:11px 14px;background:#eef2f7;color:#172033;cursor:pointer}button:hover{filter:brightness(.98)}.login-card button[type=submit],.send{width:100%;background:#183b8f;color:#fff;font-weight:700}
#app{height:100vh;display:grid;grid-template-columns:62px 290px minmax(320px,1fr) 260px;overflow:hidden}.rail{background:#111821;color:#fff;display:flex;flex-direction:column;align-items:center;padding:16px 8px;gap:14px}.railbtn{width:40px;height:40px;border-radius:12px;background:#222b36;color:#cbd5e1}.railbtn.active{background:#fff;color:#111}.railbtn.bottom{margin-top:auto;display:grid;place-items:center;text-decoration:none}.contacts{background:linear-gradient(180deg,#222933,#171d25);color:#fff;padding:18px;border-right:1px solid #0002;display:flex;flex-direction:column;gap:14px}.headbrand{margin-bottom:8px}.search input{background:#fff1;color:#fff;border-color:#ffffff20}.contact{display:flex;align-items:center;gap:12px;padding:12px;border-radius:16px;cursor:pointer}.contact.active,.contact:hover{background:#ffffff18}.contact .sub{font-size:13px;color:#9ca3af}.avatar{width:42px;height:42px;border-radius:50%;display:grid;place-items:center;background:#e5e7eb;color:#111;font-weight:800;flex:0 0 auto}.ai .avatar{background:radial-gradient(circle,#fff,#cfe1ff);box-shadow:0 0 20px #4f8cff55}.settings-link{margin-top:auto;color:#d1d5db;font-size:14px}
.chat{display:grid;grid-template-rows:72px 1fr 72px;background:#edf2f8}.chathead{display:flex;align-items:center;gap:12px;padding:12px 18px;background:#ffffffe0;border-bottom:1px solid var(--line);backdrop-filter:blur(10px)}.chathead span{display:block;color:#16a34a;font-size:13px}.head-actions{margin-left:auto;display:flex;gap:8px}.messages{padding:20px;overflow:auto;display:flex;flex-direction:column;gap:14px}.msg{max-width:min(620px,78%);display:flex;gap:8px;align-items:flex-end}.msg.mine{align-self:flex-end;flex-direction:row-reverse}.bubble{background:var(--bubble);border:1px solid var(--line);border-radius:18px;padding:12px 14px;box-shadow:0 8px 20px #0000000b}.mine .bubble{background:var(--mine)}.meta{font-size:11px;color:var(--muted);margin-top:6px;text-align:right}.filecard{display:flex;gap:10px;align-items:center;margin-top:8px;padding:10px;border-radius:14px;border:1px solid #cfd8e6;background:#fff9;text-decoration:none;color:var(--ink)}.thumb{max-width:220px;max-height:170px;border-radius:14px;border:1px solid var(--line);display:block}.copyhint{position:fixed;left:50%;bottom:92px;transform:translateX(-50%);background:#111;color:#fff;border-radius:999px;padding:9px 14px;font-size:13px;opacity:0;transition:.2s;z-index:9}.copyhint.show{opacity:1}.composer{display:flex;gap:8px;align-items:center;padding:12px 18px;background:#ffffffe8;border-top:1px solid var(--line)}.composer input{flex:1}.composer button{width:44px;height:44px;border-radius:50%;padding:0}.composer .send{width:48px}.panel{background:#ffffffe6;border-left:1px solid var(--line);padding:18px;overflow:auto}.toggle-row{display:flex;justify-content:space-between;align-items:center}.toggle-row input{width:auto}.toolgrid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.toolgrid button{min-height:78px;background:#f8fafc;border:1px solid var(--line)}.mobile-only{display:none}
@media(max-width:980px){#app{grid-template-columns:1fr}.rail,.panel{display:none}.contacts{position:absolute;z-index:5;inset:0 22% 0 0;transform:translateX(-110%);transition:.2s}.contacts.open{transform:translateX(0)}.chat{height:100vh}.mobile-only{display:inline-grid}.msg{max-width:88%}}
@media(prefers-color-scheme:dark){body{background:#121820;color:#eef2f7}.chat{background:#18202a}.chathead,.composer,.panel{background:#1f2937e8;color:#eef2f7;border-color:#344155}.bubble{background:#273240;color:#f9fafb;border-color:#3d4b5f}.mine .bubble{background:#263f70}.filecard{background:#111827;color:#fff;border-color:#3d4b5f}input,select{background:#111827;color:#fff;border-color:#374151}.toolgrid button,button{background:#2a3545;color:#fff}.contacts{background:#101720}}