:root {
  color-scheme: dark;
  --bg: #0d1117;
  --panel: #161b22;
  --border: #30363d;
  --text: #e6edf3;
  --accent: #58a6ff;
  --occupied: #f85149;
  --vacant: #3fb950;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
}
header {
  padding: 1.5rem 2rem 0.5rem;
}
header h1 { margin: 0; font-size: 1.8rem; }
.tagline { margin: 0.25rem 0 0; color: #8b949e; }
main { max-width: 900px; margin: 0 auto; padding: 1rem 2rem 3rem; }
.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.5rem;
  margin-top: 1rem;
}
label {
  display: block;
  margin-bottom: 1rem;
  font-size: 0.9rem;
  color: #8b949e;
}
input[type="text"] {
  display: block;
  width: 100%;
  margin-top: 0.35rem;
  padding: 0.5rem 0.75rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text);
  font-size: 1rem;
}
.button-row { display: flex; gap: 0.75rem; margin-top: 1rem; flex-wrap: wrap; }
button {
  padding: 0.55rem 1.1rem;
  border: none;
  border-radius: 6px;
  background: var(--accent);
  color: #0d1117;
  font-weight: 600;
  cursor: pointer;
}
button.secondary {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
}
.muted { color: #8b949e; font-size: 0.85rem; }
.main-header { display: flex; justify-content: space-between; align-items: center; }
.room-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}
.room-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem;
  background: var(--bg);
}
.room-card.occupied { border-color: var(--occupied); }
.room-card.vacant { border-color: var(--vacant); }
.room-id { font-weight: 700; font-size: 1.1rem; }
.room-status { margin-top: 0.25rem; }
.room-card.occupied .room-status { color: var(--occupied); }
.room-card.vacant .room-status { color: var(--vacant); }
.room-guest { margin-top: 0.4rem; font-size: 0.95rem; }
.room-since { margin-top: 0.15rem; font-size: 0.75rem; color: #8b949e; }
.room-action { margin-top: 0.75rem; width: 100%; }
.log-list { list-style: none; padding: 0; margin: 0; font-size: 0.9rem; }
.log-list li { padding: 0.4rem 0; border-bottom: 1px solid var(--border); }
.log-time { color: #8b949e; margin-right: 0.5rem; font-size: 0.8rem; }
dialog {
  background: var(--panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.5rem;
  min-width: 280px;
}
dialog::backdrop { background: rgba(0, 0, 0, 0.6); }