:root {
  --gap: 1rem;
  --radius: 12px;
  --border: 1px solid #e6e6e6;
  --text: #111;
  --muted: #666;
  --bg: #fafafa;
  --card: #fff;
}

* { box-sizing: border-box; }

html, body { height: 100%; }

body {
  margin: 0;
  color: var(--text);
  background: var(--bg);
  /* Moderner System-Stack ohne Webfont */
  font-family:
    ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue",
    "Noto Sans", "Liberation Sans", Arial, "Apple Color Emoji", "Segoe UI Emoji",
    "Segoe UI Symbol", "Noto Color Emoji";
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

header {
  position: sticky; top: 0;
  background: rgba(255,255,255,0.85);
  backdrop-filter: saturate(180%) blur(8px);
  padding: .9rem 1.25rem;
  border-bottom: var(--border);
  display: flex; align-items: center; gap: .75rem;
}

header h1 { font-size: 1.15rem; margin: 0; font-weight: 700; letter-spacing: .2px; }

main { max-width: 960px; margin: 2rem auto; padding: 0 1.25rem; }

.card {
  background: var(--card);
  border: var(--border);
  border-radius: var(--radius);
  padding: 1.25rem;
  box-shadow: 0 1px 0 rgba(0,0,0,.02);
}

.grid { display: grid; gap: var(--gap); }
.grid-gap { gap: 1.25rem; }
.grid-2 { grid-template-columns: repeat(2, minmax(0,1fr)); }
@media (max-width: 720px) { .grid-2 { grid-template-columns: 1fr; } }

.h2 { margin: 0 0 .75rem; font-size: 1.05rem; font-weight: 700; }

label { display: block; font-weight: 600; margin: .5rem 0 .35rem; }

input[type="text"], input[type="password"] {
  width: 100%;
  padding: .65rem .75rem;
  border: 1px solid #ddd;
  border-radius: 10px;
  background: #fff;
}

button, .btn {
  padding: .6rem .85rem;
  border: 0; border-radius: 10px;
  cursor: pointer;
  background: #111; color: #fff;
}

.nav { margin-left: auto; display: flex; gap: .75rem; }
a { color: #0a6; text-decoration: none; }
a:hover { text-decoration: underline; }

.qrwrap { display: flex; gap: 2rem; align-items: flex-start; flex-wrap: wrap; }
.qrwrap img { image-rendering: pixelated; border: 1px solid #eee; border-radius: 10px; }

.small { color: var(--muted); font-size: .9rem; }
.notice { color: #0a6; font-weight: 600; }

code, pre { background: #f6f8fa; border-radius: 8px; }
pre { padding: .6rem .8rem; overflow: auto; }

.copyrow { display: grid; grid-template-columns: 1fr auto; gap: .5rem; align-items: center; }

.codebox label { margin-bottom: .4rem; }