:root {
  --bg: #0f1720;
  --panel: #182430;
  --panel-2: #1f2e3b;
  --text: #e7edf3;
  --muted: #92a3b3;
  --accent: #ffb648;
  --accent-2: #4fd1a5;
  --danger: #ff6b6b;
  --border: #2b3947;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
}

.topbar h1 { font-size: 1.25rem; margin: 0; }

.live-badge {
  font-size: 0.8rem;
  padding: 4px 10px;
  border-radius: 999px;
  background: var(--panel-2);
  color: var(--muted);
}
.live-badge.ok { color: var(--accent-2); }
.live-badge.err { color: var(--danger); }

main {
  max-width: 1000px;
  margin: 0 auto;
  padding: 20px 24px 60px;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
}

.period-tabs { display: flex; gap: 4px; background: var(--panel); padding: 4px; border-radius: 10px; }
.tab {
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 8px 16px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
}
.tab.active { background: var(--accent); color: #1a1200; font-weight: 600; }

.nav { display: flex; align-items: center; gap: 10px; color: var(--text); }
.nav button {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 8px;
  padding: 6px 12px;
  cursor: pointer;
}
.nav button:hover { background: var(--panel-2); }
#period-label { min-width: 140px; text-align: center; font-weight: 600; }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 12px;
  margin-bottom: 28px;
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}
.card.highlight { background: var(--panel-2); border-color: var(--accent); }
.card-label { color: var(--muted); font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.04em; }
.card-value { font-size: 1.6rem; font-weight: 700; margin-top: 6px; }
.card-sub { color: var(--muted); font-size: 0.75rem; margin-top: 2px; }

.chart-section {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px 20px;
  margin-bottom: 20px;
}
.chart-section h2 { font-size: 1rem; margin: 0 0 12px; color: var(--muted); font-weight: 600; }

/* Fixed-height wrapper decoupled from Chart.js's aspect-ratio-based sizing
   (maintainAspectRatio:false in app.js), so charts are usable in portrait on
   a phone without needing to rotate to landscape. */
.chart-canvas { position: relative; height: 320px; }

.live-dot {
  color: var(--accent-2);
  font-size: 0.6rem;
  vertical-align: middle;
  animation: live-pulse 2s ease-in-out infinite;
}
@keyframes live-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.25; }
}

/* Horizontal-scroll fallback so a wide table never breaks the page layout
   on a narrow screen, even after the responsive column hiding below. */
.table-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; }
table { width: 100%; border-collapse: collapse; font-size: 0.9rem; }
th, td { text-align: left; padding: 8px 6px; border-bottom: 1px solid var(--border); white-space: nowrap; }
th { color: var(--muted); font-weight: 600; font-size: 0.8rem; text-transform: uppercase; }

footer { text-align: center; color: var(--muted); font-size: 0.8rem; padding: 20px; }

.status-online { color: var(--accent-2); }
.status-offline { color: var(--danger); }

@media (max-width: 640px) {
  main { padding: 12px 12px 40px; }
  .topbar { padding: 12px 16px; }
  .topbar h1 { font-size: 1.05rem; }
  .chart-section { padding: 12px 14px; }
  .chart-canvas { height: 240px; }
  .card-value { font-size: 1.3rem; }
  .card { padding: 12px; }
  .controls { gap: 10px; }
  .nav { width: 100%; justify-content: center; }
  th, td { padding: 6px 4px; font-size: 0.85rem; }
  /* Least essential column on a phone - drop it rather than force horizontal
     scrolling for every row; Power/Voltage/Status are what matter at a glance. */
  .col-updated { display: none; }
}