:root {
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #555555;
  --accent: #1f4e79;
  --warn-bg: #fff4e5;
  --warn-fg: #7a4100;
  --border: #d0d0d0;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121212;
    --fg: #ececec;
    --muted: #a8a8a8;
    --accent: #8ab4f8;
    --warn-bg: #3a2a10;
    --warn-fg: #ffd59a;
    --border: #3a3a3a;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.5 system-ui, -apple-system, "Segoe UI", sans-serif;
}
main { max-width: 32rem; margin: 0 auto; padding: 2rem 1rem; }
h1 { font-size: 1.5rem; }
h2 { font-size: 1.2rem; }
label { display: block; margin-top: 1rem; }
input {
  width: 100%;
  padding: 0.6rem;
  margin: 0.25rem 0 0.75rem;
  font: inherit;
  color: var(--fg);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
}
button {
  padding: 0.6rem 1.2rem;
  font: inherit;
  color: #ffffff;
  background: var(--accent);
  border: 0;
  border-radius: 6px;
  cursor: pointer;
}
button.secondary { color: var(--fg); background: transparent; border: 1px solid var(--border); }
button:disabled { opacity: 0.6; cursor: default; }
.warning {
  padding: 0.75rem 1rem;
  background: var(--warn-bg);
  color: var(--warn-fg);
  border-radius: 6px;
  font-weight: 600;
}
.qr { display: inline-block; max-width: 100%; background: #ffffff; padding: 8px; line-height: 0; }
.qr svg { display: block; max-width: 100%; height: auto; }
dt { color: var(--muted); }
dd { margin: 0 0 0.5rem; font-weight: 600; }
.actions { display: flex; gap: 0.75rem; margin-top: 1.5rem; }
code { word-break: break-all; }
#status { color: var(--muted); }