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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: #f5f5f5;
  color: #333;
}

header {
  background: white;
  padding: 2rem;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}

h1 {
  font-size: 1.8rem;
  color: #1a73e8;
}

.time-range-selector button {
  padding: 0.5rem 1rem;
  margin-left: 0.5rem;
  border: 1px solid #ddd;
  background: white;
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.2s;
  font-size: 0.9rem;
}

.time-range-selector button:hover {
  border-color: #1a73e8;
}

.time-range-selector button.active {
  background: #1a73e8;
  color: white;
  border-color: #1a73e8;
}

main {
  max-width: 1400px;
  margin: 2rem auto;
  padding: 0 2rem;
}

.summary-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.card {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.card h3 {
  font-size: 0.9rem;
  color: #666;
  margin-bottom: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.metric {
  font-size: 2rem;
  font-weight: bold;
  color: #1a73e8;
}

.charts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.chart-container {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  height: 350px;
}

.chart-container.full-width {
  grid-column: 1 / -1;
}

.chart-container h3 {
  margin-bottom: 1rem;
  color: #333;
  font-size: 1.1rem;
}

.chart-container canvas {
  max-height: 280px;
}

.recent-errors {
  background: white;
  padding: 1.5rem;
  border-radius: 8px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.recent-errors h3 {
  margin-bottom: 1rem;
  color: #333;
  font-size: 1.1rem;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th, td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid #eee;
}

th {
  background: #f9f9f9;
  font-weight: 600;
  color: #666;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

td {
  font-size: 0.9rem;
}

tr:hover {
  background: #f9f9f9;
}

tbody tr:last-child td {
  border-bottom: none;
}

@media (max-width: 768px) {
  header {
    flex-direction: column;
    align-items: flex-start;
  }

  h1 {
    font-size: 1.5rem;
  }

  .summary-cards {
    grid-template-columns: 1fr;
  }

  .charts {
    grid-template-columns: 1fr;
  }

  .chart-container {
    height: 300px;
  }

  table {
    font-size: 0.8rem;
  }

  th, td {
    padding: 0.5rem;
  }
}