:root {
    --bg: #f5f7fa; --card: #fff; --text: #1d2733; --muted: #5d6b7a;
    --border: #c5ced8; --accent: #2b6cb0;
  }
  @media (prefers-color-scheme: dark) {
    :root { --bg: #141a21; --card: #1e2730; --text: #e8edf2; --muted: #97a4b2; --border: #3a4652; --accent: #63a4e8; }
  }
  * { box-sizing: border-box; }
  html, body { height: 100%; margin: 0; }
  body {
    display: flex; flex-direction: column;
    background: var(--bg); color: var(--text);
    font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
  }
  header {
    display: flex; flex-wrap: wrap; align-items: center; gap: 1rem;
    padding: 0.75rem 1.25rem; background: var(--card); border-bottom: 1px solid var(--border);
  }
  h1 { font-size: 1.1rem; margin: 0; flex: 1 1 auto; }
  .lang { display: flex; align-items: center; gap: 0.5rem; }
  .lang label { color: var(--muted); font-size: 0.9rem; }
  select {
    padding: 0.45rem 0.6rem; font-size: 1rem; color: var(--text);
    background: var(--card); border: 1px solid var(--border); border-radius: 8px;
  }
  select:focus-visible, a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
  main { flex: 1 1 auto; min-height: 0; display: flex; flex-direction: column; }
  iframe { flex: 1 1 auto; width: 100%; border: 0; background: var(--card); }
  #status { padding: 1rem 1.25rem; color: var(--muted); }
  #status a { color: var(--accent); }
  [hidden] { display: none !important; }