:root{
  --bg:#fff;--soft:#f7f7f8;--soft2:#efeff0;--text:#151515;--muted:#7b8190;--border:#e5e7eb;--accent:#10a37f;--blue:#0f6fff;--shadow:0 12px 35px rgba(0,0,0,.08);--danger:#b91c1c;--danger-bg:#fff1f1;--radius:24px;--sidebar:320px;font-family:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif
}
*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg);color:var(--text);min-height:100vh}button,input,textarea,select{font:inherit}button{border:0;cursor:pointer}a{text-decoration:none;color:inherit}.app{display:flex;min-height:100vh}.sidebar{width:var(--sidebar);background:var(--soft);border-right:1px solid var(--border);padding:22px 12px;display:flex;flex-direction:column;position:fixed;top:0;bottom:0;left:0;z-index:20}.brand{display:flex;align-items:center;gap:12px;padding:0 10px 18px}.brand-logo{width:42px;height:42px;border-radius:50%;display:grid;place-items:center;color:white;background:linear-gradient(135deg,#10a37f,#0f6fff);font-weight:900}.brand h1{font-size:26px;letter-spacing:-.04em}.brand p{font-size:13px;color:var(--muted);margin-top:5px}.new-chat{background:#efeff0;width:100%;border-radius:13px;text-align:left;padding:14px 16px;font-weight:600;margin-bottom:24px}.new-chat:hover,.admin-link:hover{background:#e8e8ea}.sidebar-section{padding:0 10px;flex:1;overflow:auto}.sidebar-section h2{font-size:16px;margin-bottom:14px}.history-list{display:flex;flex-direction:column;gap:4px}.history-item{padding:10px 8px;border-radius:10px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:#111;background:transparent}.history-item:hover{background:#eee}.admin-link{display:block;margin:10px 6px;padding:12px;border-radius:12px;font-weight:700}.sidebar-user{display:flex;align-items:center;gap:12px;border-radius:16px;padding:12px 10px}.sidebar-user:hover{background:#ededee}.user-avatar{width:40px;height:40px;border-radius:50%;background:#22c55e;color:#fff;display:grid;place-items:center;font-weight:900}.sidebar-user strong{display:block;font-size:15px}.sidebar-user span{font-size:13px;color:var(--muted)}.main{margin-left:var(--sidebar);width:calc(100% - var(--sidebar));min-height:100vh;position:relative;padding-bottom:96px}.topbar{height:70px;border-bottom:1px solid var(--border);display:flex;align-items:center;justify-content:space-between;padding:0 24px;background:#fff;position:sticky;top:0;z-index:10}.menu-btn{display:none;background:#fff;font-size:22px}.status{font-weight:700;color:#4b5563}.status span{display:inline-block;width:10px;height:10px;background:var(--accent);border-radius:50%;margin-right:7px;box-shadow:0 0 0 4px rgba(16,163,127,.12)}.top-actions{display:flex;align-items:center;gap:10px}.plus-pill{background:rgba(16,163,127,.13);color:#08775d;border-radius:999px;padding:12px 18px;font-weight:900}.model-select,.theme-btn{border:1px solid var(--border);background:#fff;border-radius:18px;padding:12px 18px;color:#4b5563}.theme-btn{padding:12px 16px}.welcome{height:calc(100vh - 170px);display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;padding:20px}.welcome h2{font-size:34px;font-weight:500;letter-spacing:-.04em;margin-bottom:24px}.welcome h2 span{font-weight:900;background:linear-gradient(90deg,var(--accent),var(--blue));-webkit-background-clip:text;background-clip:text;color:transparent}.chips{display:flex;gap:12px;flex-wrap:wrap;justify-content:center}.chips button{border:1px solid var(--border);background:#fff;border-radius:16px;padding:14px 18px;color:#374151}.chips button:hover{background:var(--soft)}.chat{max-width:980px;margin:0 auto;padding:24px 20px 30px}.message{display:flex;gap:16px;margin:18px 0;animation:up .22s ease both}.message.user{justify-content:flex-end}.avatar{width:38px;height:38px;border-radius:50%;display:grid;place-items:center;flex:0 0 38px;background:linear-gradient(135deg,#10a37f,#0f6fff);color:#fff;font-weight:900;font-size:13px}.message.user .avatar{display:none}.bubble{max-width:76%;padding:18px 20px;border-radius:20px;line-height:1.65;border:1px solid var(--border);background:#fff;box-shadow:0 2px 12px rgba(0,0,0,.03);white-space:pre-wrap}.message.user .bubble{background:#f7f7f8;border:0}.message.error .bubble{background:var(--danger-bg);border-color:#fecaca;color:var(--danger)}.meta{font-size:12px;color:var(--muted);margin-top:8px}.composer{position:fixed;left:calc(var(--sidebar) + 10%);right:10%;bottom:34px;display:flex;align-items:flex-end;gap:10px;background:#fff;border:1px solid #d9dbe1;border-radius:28px;padding:10px 12px;box-shadow:var(--shadow);z-index:15}.composer textarea{flex:1;border:0;outline:0;resize:none;max-height:180px;min-height:42px;padding:12px 6px;font-size:16px}.send-btn,.clear-btn{width:48px;height:48px;border-radius:50%;display:grid;place-items:center}.send-btn{background:#0b0b0c;color:white;font-size:20px}.clear-btn{background:var(--soft2)}.note{position:fixed;bottom:8px;left:var(--sidebar);right:0;text-align:center;font-size:12px;color:#929292}.admin-page{min-height:100vh;background:var(--soft);padding:28px}.admin-card{max-width:980px;margin:auto;background:#fff;border:1px solid var(--border);border-radius:26px;box-shadow:var(--shadow);padding:28px}.admin-head{display:flex;gap:16px;align-items:center;margin-bottom:18px}.admin-head h1{font-size:30px}.admin-head p{color:var(--muted);margin-top:6px}.alert{padding:14px 16px;border-radius:16px;margin:18px 0;line-height:1.5}.alert.info{background:#ecfeff;border:1px solid #a5f3fc}.admin-form{display:grid;gap:10px;margin:20px 0}.admin-form input{border:1px solid var(--border);border-radius:14px;padding:14px}.btn-primary{background:var(--accent);color:#fff;border-radius:14px;padding:14px 18px;font-weight:800}.codebox{background:#111827;color:#e5e7eb;padding:16px;border-radius:16px;overflow:auto;margin:18px 0;line-height:1.5}.back-link{display:inline-block;font-weight:800;color:#08775d;margin-top:10px}code{background:#f1f5f9;border:1px solid #e2e8f0;border-radius:6px;padding:2px 5px}@keyframes up{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}body.dark{--bg:#212121;--soft:#171717;--soft2:#2f2f2f;--text:#f3f4f6;--muted:#a6a6a6;--border:#343541}body.dark .main,body.dark .topbar,body.dark .composer,body.dark .bubble,body.dark .chips button,body.dark .model-select,body.dark .theme-btn,body.dark .admin-card{background:#212121;color:#f3f4f6}body.dark .sidebar{background:#171717}body.dark .new-chat,body.dark .message.user .bubble{background:#2f2f2f}@media(max-width:900px){:root{--sidebar:0px}.sidebar{transform:translateX(-100%);transition:.25s;width:300px}.sidebar.open{transform:translateX(0);box-shadow:var(--shadow)}.main{margin-left:0;width:100%}.menu-btn{display:block}.composer{left:12px;right:12px}.note{left:0}.topbar{padding:0 12px}.plus-pill{display:none}.welcome h2{font-size:27px}.bubble{max-width:88%}}