:root {
  /* Color variables */
  --primary-color: #2C3E50;
  --secondary-color: #ECF0F1;
  --temp-color: #E74C3C;
  --temp-gradient: linear-gradient(135deg, #F39C12, #E74C3C);
  --humid-color: #3498DB;
  --humid-gradient: linear-gradient(135deg, #3498DB, #2980B9);
  --accent-color: #27AE60;
  --background-color: #F8F9FA;
  --card-background: #FFFFFF;
  --text-primary: #2C3E50;
  --text-secondary: #7F8C8D;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  
  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

/* Dark mode variables */
.dark-mode {
  --primary-color: #1a2530;
  --secondary-color: #2C3E50;
  --background-color: #121212;
  --card-background: #1E1E1E;
  --text-primary: #ECF0F1;
  --text-secondary: #BDC3C7;
  --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

body {
  font-family: var(--font-family);
  background-color: var(--background-color);
  color: var(--text-primary);
  margin: 0;
  padding: 0;
  transition: background-color 0.3s ease;
}

/* Navbar styling */
.navbar {
  background-color: var(--primary-color) !important;
  box-shadow: var(--shadow);
}

.navbar-brand, .nav-link {
  color: var(--secondary-color) !important;
}

.nav-link:hover {
  color: var(--accent-color) !important;
}

/* Dashboard container */
.dashboard-container {
  padding: 24px;
}

/* Card styling */
.dashboard-card {
  background-color: var(--card-background);
  border-radius: 8px;
  box-shadow: var(--shadow);
  margin-bottom: 24px;
  overflow: hidden;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.dashboard-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px;
  border-bottom: 1px solid rgba(0,0,0,0.05);
}

.card-body {
  padding: 16px;
}

.card-header h3 {
  margin: 0;
  font-size: 18px;
  font-weight: 600;
}

.card-actions {
  display: flex;
}

.btn-icon {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  transition: background-color 0.2s ease;
}

.btn-icon:hover {
  background-color: rgba(0,0,0,0.05);
  color: var(--text-primary);
}

/* Current value display */
.current-value {
  display: flex;
  align-items: baseline;
  margin-bottom: 16px;
}

.current-value .value {
  font-size: 36px;
  font-weight: 600;
}

.current-value .unit {
  font-size: 18px;
  margin-left: 4px;
  color: var(--text-secondary);
}

.current-value .trend {
  margin-left: 12px;
  font-size: 14px;
  padding: 4px 8px;
  border-radius: 4px;
}

.trend.up {
  background-color: rgba(39, 174, 96, 0.1);
  color: #27AE60;
}

.trend.down {
  background-color: rgba(231, 76, 60, 0.1);
  color: #E74C3C;
}

/* Card types */
.temperature-card .card-header {
  border-top: 3px solid var(--temp-color);
}

.humidity-card .card-header {
  border-top: 3px solid var(--humid-color);
}

/* Chart container */
.chart-container {
  height: 400px;
  margin-top: 16px;
}

/* Card footer with stats */
.card-footer {
  display: flex;
  justify-content: space-between;
  padding: 12px 16px;
  background-color: rgba(0,0,0,0.02);
  border-top: 1px solid rgba(0,0,0,0.05);
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.stat-item .label {
  font-size: 12px;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.stat-item .value {
  font-size: 14px;
  font-weight: 500;
}

/* Date range form */
.date-range-form {
  margin-bottom: 24px;
}

.btn-secondary {
  background-color: var(--secondary-color);
  border: none;
  margin-right: 8px;
}

.btn-secondary:hover {
  background-color: var(--primary-color);
}

.btn-primary {
  background-color: var(--accent-color);
  border: none;
}

.btn-primary:hover {
  background-color: #219653;
}

/* Dark mode toggle */
.dark-mode-toggle {
  background-color: var(--primary-color);
  color: var(--secondary-color);
  border: none;
  border-radius: 50%;
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  margin-right: 10px;
  vertical-align: middle;
  transition: background-color 0.3s ease;
}

.dark-mode-toggle:hover {
  background-color: var(--accent-color);
}

/* Responsive grid */
@media (max-width: 768px) {
  .dashboard-container {
    padding: 16px;
  }
  
  .current-value .value {
    font-size: 28px;
  }
  
  .chart-container {
    height: 300px;
  }
}

/* Footer styling */
.footer {
  background-color: var(--primary-color);
  color: var(--secondary-color);
  padding: 16px 0;
  margin-top: 24px;
  position: sticky;
  bottom: 0;
  width: 100%;
}

/* Ensure minimum height for content to push footer down */
html, body {
  height: 100%;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.dashboard-container {
  flex: 1;
}

.footer a {
  color: var(--accent-color);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}