@media (prefers-color-scheme: dark) {
  html[data-theme="system"] { --ink:#eef5fa; --muted:#91a2b1; --line:#283847; --panel:#182533; --soft:#111c27; }
  html[data-theme="system"] body, html[data-theme="system"] .sidebar, html[data-theme="system"] .chat-head, html[data-theme="system"] .composer { background:#182533; }
  html[data-theme="system"] input, html[data-theme="system"] textarea, html[data-theme="system"] .panel, html[data-theme="system"] .modal { background:#1c2b39; color:var(--ink); }
  html[data-theme="system"] .messages { background-color:#101c27; }
}
html[data-theme="dark"] { --ink:#eef5fa; --muted:#91a2b1; --line:#283847; --panel:#182533; --soft:#111c27; }
html[data-theme="dark"] body, html[data-theme="dark"] .sidebar, html[data-theme="dark"] .chat-head, html[data-theme="dark"] .composer { background:#182533; }
html[data-theme="dark"] input, html[data-theme="dark"] textarea, html[data-theme="dark"] .panel, html[data-theme="dark"] .modal { background:#1c2b39; color:var(--ink); }
html[data-theme="dark"] .messages { background-color:#101c27; }