/* main.css — variables, reset y layout global. Versión 3.0.0 */

:root {
  --bg-primary:    #0F1923;
  --bg-surface:    #1C2B38;
  --bg-surface2:   #243447;
  --bg-hover:      #2D3F52;
  --accent-cyan:   #00C8C8;
  --accent-amber:  #F5A623;
  --text-primary:  #E8F0F7;
  --text-secondary:#8899AA;
  --text-label:    #6677AA;
  --success:       #00C864;
  --error:         #FF4444;
  --warning-bg:    #FFF3CD;
  --warning-text:  #856404;
  --alarm-bg:      #FFE0B2;
  --alarm-text:    #BF360C;
  --relay-on-bg:   rgba(0, 200, 100, 0.08);
  --relay-off-bg:  rgba(0, 150, 255, 0.08);
  --relay-cyc-bg:  rgba(245, 166, 35, 0.08);
  --border:        rgba(255,255,255,0.08);
  --radius:        6px;
  --radius-lg:     10px;
  --font-mono:     'JetBrains Mono', 'Fira Code', monospace;
  --font-ui:       'Inter', system-ui, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-ui);
  font-size: 14px;
  min-height: 100vh;
}

a { color: var(--accent-cyan); }

/* ─────────────────────────── Header ─────────────────────────── */

.app-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1.25rem;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 50;
}

.site-name { font-weight: 600; font-size: 1.05rem; }

.mqtt-indicator {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.mqtt-indicator.reconnecting { color: var(--accent-amber); }

/* ─────────────────────────── Tabs ─────────────────────────── */

.tab-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  padding: 0.5rem 0.75rem;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 49px;
  z-index: 40;
  overflow-x: auto;
}

.tab-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 0.85rem;
  white-space: nowrap;
  transition: background 0.15s, color 0.15s;
}

.tab-btn:hover { background: var(--bg-hover); color: var(--text-primary); }

.tab-btn.active {
  background: var(--bg-surface2);
  color: var(--accent-cyan);
  font-weight: 600;
}

.tab-content { padding: 1rem 1.25rem 3rem; max-width: 1600px; margin: 0 auto; }

.tab-panel.hidden { display: none; }

.tab-panel.active { display: block; }

/* ─────────────────────────── Layout helpers ─────────────────────────── */

.section { margin-bottom: 1.5rem; }

.section-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.6rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.two-col { display: flex; gap: 1rem; }
.two-col > * { flex: 1 1 0; min-width: 0; }

.chart-grid-2x2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.empty-state {
  color: var(--text-secondary);
  font-size: 0.9rem;
  padding: 2rem;
  text-align: center;
  background: var(--bg-surface);
  border-radius: var(--radius-lg);
}