:root {
  --surface-1: #fcfcfb;
  --page: #f9f9f7;
  --text-primary: #0b0b0b;
  --text-secondary: #52514e;
  --text-muted: #898781;
  --gridline: #e1e0d9;
  --baseline: #c3c2b7;
  --border: rgba(11, 11, 11, 0.10);
  --series-1: #2a78d6;
  --good: #0ca30c;
  --critical: #d03b3b;
}

@media (prefers-color-scheme: dark) {
  :root {
    --surface-1: #1a1a19;
    --page: #0d0d0d;
    --text-primary: #ffffff;
    --text-secondary: #c3c2b7;
    --text-muted: #898781;
    --gridline: #2c2c2a;
    --baseline: #383835;
    --border: rgba(255, 255, 255, 0.10);
    --series-1: #3987e5;
    --good: #0ca30c;
    --critical: #e66767;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--page);
  color: var(--text-primary);
  font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
}

nav {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.75rem 1.25rem;
  background: var(--surface-1);
  border-bottom: 1px solid var(--border);
}

nav a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.95rem;
}

nav a.active, nav a:hover { color: var(--text-primary); }

nav form { margin-left: auto; }

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
}

h1, h2, h3 { color: var(--text-primary); }

.site-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1rem;
}

.site-card, .device-card {
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1rem 1.25rem;
}

.site-card {
  text-decoration: none;
  color: var(--text-primary);
  display: block;
}

.device-card { margin-bottom: 1.25rem; }

.device-card h3 { margin-top: 0; }

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 0.75rem;
  margin: 0.75rem 0;
}

.stat-tile {
  background: var(--page);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.6rem 0.8rem;
}

.stat-tile .label {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.stat-tile .value {
  font-size: 1.4rem;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
}

.stat-tile .unit {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.stat-tile .time {
  font-size: 0.7rem;
  color: var(--text-muted);
}

.empty { color: var(--text-muted); font-style: italic; }

.relay-buttons { display: flex; gap: 0.6rem; flex-wrap: wrap; margin-bottom: 0.5rem; }

.relay-buttons button {
  border: 1px solid var(--border);
  background: var(--page);
  color: var(--text-primary);
  border-radius: 6px;
  padding: 0.4rem 0.9rem;
  cursor: pointer;
  font-size: 0.9rem;
}

.relay-buttons button.on { border-color: var(--good); color: var(--good); }
.relay-buttons button.off { border-color: var(--critical); color: var(--critical); }
.relay-buttons button:hover { filter: brightness(0.95); }

.history-controls {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  margin-top: 0.75rem;
  flex-wrap: wrap;
}

.history-controls select, .history-controls button {
  border: 1px solid var(--border);
  background: var(--page);
  color: var(--text-primary);
  border-radius: 6px;
  padding: 0.3rem 0.6rem;
  font-size: 0.85rem;
}

.history-controls button.active { border-color: var(--series-1); color: var(--series-1); }

.history-chart-wrap { margin-top: 0.5rem; height: 220px; }

.login-wrap {
  max-width: 320px;
  margin: 4rem auto;
  background: var(--surface-1);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.5rem;
}

.login-wrap label { display: block; margin: 0.75rem 0 0.25rem; font-size: 0.85rem; color: var(--text-secondary); }
.login-wrap input {
  width: 100%;
  padding: 0.5rem;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--page);
  color: var(--text-primary);
}
.login-wrap button {
  margin-top: 1.25rem;
  width: 100%;
  padding: 0.6rem;
  border-radius: 6px;
  border: none;
  background: var(--series-1);
  color: white;
  font-size: 1rem;
  cursor: pointer;
}
.login-error { color: var(--critical); font-size: 0.85rem; margin-top: 0.75rem; }