:root[data-theme="light"]{color-scheme:light;--bg:#f7f7f8;--panel:#ffffff;--panel2:#f0f0f2;--panel3:#e7e7ea;--border:#d8d8dc;--text:#161618;--muted:#707078;--accent:#151517;--accentText:#fff;--danger:#c9414b;--sidebar:#f1f1f3}html[data-theme="light"] body{background:var(--bg);color:var(--text)}html[data-theme="light"] .topbar{background:rgba(247,247,248,.9)}html[data-theme="light"] .auth-screen{background:radial-gradient(circle at 50% 10%,#fff 0,#f7f7f8 52%)}html[data-theme="light"] .auth-card{background:rgba(255,255,255,.94);box-shadow:0 30px 100px rgba(0,0,0,.08)}html[data-theme="light"] input,html[data-theme="light"] textarea,html[data-theme="light"] select{background:#fff;color:var(--text)}html[data-theme="light"] .message.assistant .avatar{background:#151517;color:#fff}html[data-theme="light"] .composer{box-shadow:0 18px 50px rgba(0,0,0,.08)}.theme-toggle{width:36px;height:36px;border:1px solid var(--border);border-radius:10px;background:var(--panel);display:grid;place-items:center;cursor:pointer;font-size:16px;flex:0 0 auto}.theme-toggle:hover{background:var(--panel2)}.topbar-actions{display:flex;align-items:center;gap:8px}@media(max-width:800px){.theme-toggle{width:34px;height:34px}.topbar-actions .user-label{display:none}}