:root {
  --bg-primary: #121927;
  --bg-surface: rgba(26, 36, 56, 0.88);
  --bg-card: rgba(27, 38, 59, 0.75);
  --bg-card-solid: #1b263b;
  --bg-hover: #26354f;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);
  --glow-accent: rgba(56, 189, 248, 0.09);
  --grid-dot: rgba(255, 255, 255, 0.05);
  --accent-blue: #0284c7;
  --accent-cyan: #06b6d4;
  --accent-green: #10b981;
  --accent-amber: #f59e0b;
  --accent-red: #ef4444;
  --accent-purple: #a855f7;
  --shadow: 0 4px 16px -2px rgba(0, 0, 0, 0.28), inset 0 1px 0 rgba(255, 255, 255, 0.06);
  --radius: 10px;
}

[data-theme="light"] {
  --bg-primary: #f3f6fa;
  --bg-surface: rgba(255, 255, 255, 0.92);
  --bg-card: rgba(255, 255, 255, 0.88);
  --bg-card-solid: #ffffff;
  --bg-hover: #eef2f7;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border: rgba(0, 0, 0, 0.08);
  --border-strong: rgba(0, 0, 0, 0.15);
  --glow-accent: rgba(2, 132, 199, 0.06);
  --grid-dot: rgba(15, 23, 42, 0.04);
  --shadow: 0 4px 12px -2px rgba(0, 0, 0, 0.06), inset 0 1px 0 rgba(255, 255, 255, 0.8);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-primary);
  background-image: 
    radial-gradient(ellipse 75% 45% at 50% -10%, var(--glow-accent), transparent 70%),
    radial-gradient(circle at 1px 1px, var(--grid-dot) 1px, transparent 0);
  background-size: 100% 100%, 24px 24px;
  background-attachment: fixed;
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.45;
  padding-bottom: 2rem;
}

header {
  background-color: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
}

.header-container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0.65rem 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo-area {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.logo-icon {
  width: 28px;
  height: 28px;
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-cyan));
  border-radius: 7px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: 700;
  font-size: 0.875rem;
  box-shadow: 0 2px 6px rgba(2, 132, 199, 0.35);
}

h1 {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.2rem 0.55rem;
  font-size: 0.725rem;
  font-weight: 600;
  border-radius: 9999px;
  background: rgba(2, 132, 199, 0.12);
  color: #38bdf8;
  border: 1px solid rgba(56, 189, 248, 0.25);
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--accent-green);
  box-shadow: 0 0 6px var(--accent-green);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.45; transform: scale(0.85); }
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.38rem 0.8rem;
  border-radius: 6px;
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.15s ease;
  border: 1px solid var(--border);
  background: var(--bg-surface);
  color: var(--text-primary);
}

.btn:hover {
  background: var(--bg-hover);
  border-color: var(--border-strong);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-blue), #0369a1);
  color: white;
  border-color: rgba(56, 189, 248, 0.3);
  box-shadow: 0 2px 8px rgba(2, 132, 199, 0.25);
}

.btn-primary:hover {
  background: linear-gradient(135deg, #0284c7, #075985);
}

.btn-success {
  background: linear-gradient(135deg, var(--accent-green), #059669);
  color: white;
  border-color: rgba(16, 185, 129, 0.3);
  box-shadow: 0 2px 8px rgba(16, 185, 129, 0.2);
}

.btn-success:hover {
  background: linear-gradient(135deg, #059669, #047857);
}

.main-container {
  max-width: 1280px;
  margin: 1rem auto;
  padding: 0 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

/* Source Tabs Navigation */
.tabs-nav {
  display: flex;
  gap: 0.35rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  padding: 0.25rem;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.tab-btn {
  flex: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.45rem 1rem;
  border-radius: 7px;
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  background: transparent;
  color: var(--text-secondary);
  border: none;
  transition: all 0.18s ease;
}

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

.tab-btn.active {
  background: linear-gradient(135deg, var(--accent-blue), #0369a1);
  color: white;
  box-shadow: 0 2px 6px rgba(2, 132, 199, 0.3);
}

.tab-btn .tab-badge {
  font-size: 0.725rem;
  padding: 0.1rem 0.45rem;
  border-radius: 9999px;
  background: rgba(255, 255, 255, 0.2);
  font-weight: 700;
}

.tab-content {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  animation: fadeIn 0.2s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(4px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.85rem 1.15rem;
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.kpi-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.35rem;
}

.kpi-title {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.kpi-value-row {
  display: flex;
  align-items: baseline;
  gap: 0.4rem;
}

.kpi-big-num {
  font-size: 1.85rem;
  font-weight: 700;
  line-height: 1.1;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.kpi-unit {
  font-size: 0.95rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.kpi-footer {
  margin-top: 0.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.725rem;
  color: var(--text-muted);
}

/* Gym Workload Gauge */
.gauge-container {
  margin-top: 0.45rem;
  height: 6px;
  background: rgba(255, 255, 255, 0.08);
  border-radius: 9999px;
  overflow: hidden;
}

.gauge-bar {
  height: 100%;
  border-radius: 9999px;
  transition: width 0.4s ease-out;
}

/* Electricity Mix Pill Grid */
.mix-pills {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.45rem;
  margin-top: 0.45rem;
}

@media (max-width: 680px) {
  .mix-pills {
    grid-template-columns: repeat(2, 1fr);
  }
}

.mix-pill {
  background: rgba(255, 255, 255, 0.025);
  border: 1px solid var(--border);
  padding: 0.35rem 0.65rem;
  border-radius: 6px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-inline-start: 3px solid var(--pill-color, var(--accent-blue));
}

.mix-pill-name {
  font-size: 0.775rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.pill-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--pill-color, var(--accent-blue));
}

.mix-pill-val {
  font-size: 0.825rem;
  font-weight: 700;
  color: var(--text-primary);
}

/* Controls Panel */
.controls-panel {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  align-items: center;
  justify-content: space-between;
  padding: 0.55rem 0.95rem;
}

.control-group {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.45rem;
}

.control-label {
  font-size: 0.775rem;
  color: var(--text-secondary);
  font-weight: 500;
}

select, input[type="datetime-local"], input[type="text"] {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 0.32rem 0.65rem;
  border-radius: 6px;
  font-size: 0.8rem;
  outline: none;
  transition: border-color 0.15s;
}

select:focus, input:focus {
  border-color: var(--accent-blue);
}

.preset-pills {
  display: flex;
  gap: 0.18rem;
  background: var(--bg-surface);
  padding: 0.18rem;
  border-radius: 6px;
  border: 1px solid var(--border);
}

.preset-pill {
  padding: 0.2rem 0.55rem;
  font-size: 0.775rem;
  border-radius: 4px;
  cursor: pointer;
  background: transparent;
  color: var(--text-secondary);
  border: none;
  transition: all 0.15s ease;
}

.preset-pill.active {
  background: var(--accent-blue);
  color: white;
  font-weight: 600;
}

/* Chart Container */
.chart-card {
  position: relative;
  display: flex;
  flex-direction: column;
  padding: 0.85rem 1.15rem;
}

.chart-header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
  gap: 0.5rem;
}

.chart-header h3 {
  font-size: 0.95rem;
  font-weight: 600;
}

.series-toggles {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.series-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.725rem;
  padding: 0.2rem 0.55rem;
  border-radius: 5px;
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.03);
  cursor: pointer;
  user-select: none;
  transition: all 0.15s ease;
}

.series-chip.active {
  border-color: currentColor;
  background: rgba(255, 255, 255, 0.09);
  box-shadow: inset 0 0 0 1px currentColor;
}

.chart-wrapper {
  position: relative;
  height: 330px;
  width: 100%;
  overflow: hidden;
  border-radius: 8px;
}

.chart-wrapper canvas {
  display: block;
  width: 100%;
  height: 100%;
  box-sizing: border-box;
}

/* Modal Backdrop & Card */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
}

.modal-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: 12px;
  box-shadow: 0 16px 40px -4px rgba(0, 0, 0, 0.5);
  width: 100%;
  max-width: 380px;
  padding: 1.75rem;
  text-align: center;
  animation: fadeIn 0.25s ease-out;
}

.modal-icon {
  font-size: 2.2rem;
  display: inline-block;
  margin-bottom: 0.6rem;
}

.modal-header h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
  color: var(--text-primary);
}

.modal-header p {
  font-size: 0.825rem;
  color: var(--text-secondary);
  line-height: 1.4;
  margin-bottom: 1.25rem;
}

.modal-form {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.modal-form input[type="password"] {
  width: 100%;
  padding: 0.65rem 0.95rem;
  font-size: 0.95rem;
  text-align: center;
  letter-spacing: 0.1em;
}

.auth-error {
  color: var(--accent-red);
  font-size: 0.785rem;
  font-weight: 500;
}

.btn-block {
  width: 100%;
  justify-content: center;
  padding: 0.6rem 1rem;
  font-size: 0.875rem;
}

/* Toast notification */
.toast {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  padding: 0.75rem 1.25rem;
  border-radius: 8px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  color: var(--text-primary);
  font-size: 0.875rem;
  display: none;
  z-index: 100;
  animation: slideUp 0.2s ease-out;
}

@keyframes slideUp {
  from { transform: translateY(20px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

@media (max-width: 768px) {
  .header-container { flex-direction: column; align-items: flex-start; gap: 0.75rem; }
  .controls-panel { flex-direction: column; align-items: stretch; }
  .control-group { justify-content: space-between; }
  .chart-wrapper { height: 280px; }
}