:root {
  --bg-color: #0f172a;
  --card-bg: #1e293b;
  --border-color: #334155;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --accent-light: #38bdf8;
  --accent-dark: #0284c7;
}

body {
  background-color: var(--bg-color);
  color: var(--text-primary);
  font-family: 'Poppins', sans-serif;
  margin: 0;
  padding: 1rem;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  text-align: center;
}

header {
  margin-bottom: 1rem;
}

h1 {
  color: var(--accent-light);
  font-size: 2.2rem;
  font-weight: 700;
  margin: 0;
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.1rem;
}

#update-time {
  color: var(--text-secondary);
  font-style: italic;
  margin: 1rem 0;
}

.stats-container {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.stat-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.5rem 2rem;
  width: 250px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.stat-card h2 {
  color: var(--text-secondary);
  font-size: 1rem;
  margin-bottom: 0.5rem;
  text-transform: uppercase;
}

.stat-card p {
  font-size: 2.5rem;
  font-weight: 600;
}

.chart-container {
  background: var(--card-bg);
  border-radius: 12px;
  border: 1px solid var(--border-color);
  padding: 1rem;
  height: 50vh;
}

@media (max-width: 768px) {
  .stats-container {
    flex-direction: column;
    align-items: center;
  }
  .chart-container {
    height: 60vh;
  }
}