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

:root {
  --bg-primary: #0f0f23;
  --bg-secondary: #1a1a2e;
  --bg-card: #16213e;
  --bg-card-hover: #1c2a4a;
  --border-color: #2a2a4a;
  --text-primary: #e0e0e0;
  --text-secondary: #a0a0b8;
  --text-muted: #6a6a8a;
  --accent-blue: #4fc3f7;
  --accent-green: #66bb6a;
  --accent-red: #ef5350;
  --accent-orange: #ffa726;
  --accent-purple: #ab47bc;
  --accent-cyan: #26c6da;
  --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
}

.header {
  background: linear-gradient(135deg, var(--bg-secondary), var(--bg-card));
  padding: 20px 32px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header h1 {
  font-size: 24px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  letter-spacing: 1px;
}

.header .header-subtitle {
  font-size: 13px;
  color: var(--text-muted);
}

.filter-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 16px 32px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  flex-wrap: wrap;
}

.filter-bar label {
  font-size: 14px;
  color: var(--text-secondary);
  font-weight: 500;
}

.filter-bar input[type="date"] {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 14px;
  outline: none;
  transition: border-color 0.2s;
}

.filter-bar input[type="date"]:focus {
  border-color: var(--accent-blue);
}

.filter-bar input[type="date"]::-webkit-calendar-picker-indicator {
  filter: invert(0.7);
  cursor: pointer;
}

.filter-bar .quick-buttons {
  display: flex;
  gap: 8px;
  margin-left: 8px;
}

.quick-btn {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 8px 18px;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s;
  font-weight: 500;
}

.quick-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-blue);
  color: var(--text-primary);
}

.quick-btn.active {
  background: linear-gradient(135deg, rgba(79, 195, 247, 0.15), rgba(38, 198, 218, 0.15));
  border-color: var(--accent-blue);
  color: var(--accent-blue);
  font-weight: 600;
}

.kpi-section {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 16px;
  padding: 24px 32px;
}

.kpi-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 20px 24px;
  transition: all 0.3s;
  position: relative;
  overflow: hidden;
}

.kpi-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-cyan));
  opacity: 0;
  transition: opacity 0.3s;
}

.kpi-card:hover {
  border-color: var(--accent-blue);
  transform: translateY(-2px);
  box-shadow: var(--shadow);
}

.kpi-card:hover::before {
  opacity: 1;
}

.kpi-card .kpi-label {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 8px;
  font-weight: 500;
}

.kpi-card .kpi-value {
  font-size: 28px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.5px;
}

.kpi-card .kpi-change {
  font-size: 13px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 4px;
}

.kpi-change.up {
  color: var(--accent-green);
}

.kpi-change.down {
  color: var(--accent-red);
}

.kpi-change.neutral {
  color: var(--text-muted);
}

.charts-section {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  padding: 0 32px 24px;
}

.chart-container {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 20px;
  min-height: 400px;
  transition: border-color 0.3s;
}

.chart-container:hover {
  border-color: rgba(79, 195, 247, 0.3);
}

.chart-container .chart-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.footer {
  text-align: center;
  padding: 20px 32px;
  color: var(--text-muted);
  font-size: 12px;
  border-top: 1px solid var(--border-color);
  margin-top: 8px;
}

@media (max-width: 1200px) {
  .kpi-section {
    grid-template-columns: repeat(3, 1fr);
  }

  .charts-section {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .header {
    padding: 16px 20px;
    flex-direction: column;
    align-items: flex-start;
    gap: 4px;
  }

  .header h1 {
    font-size: 20px;
  }

  .filter-bar {
    padding: 12px 20px;
    gap: 8px;
  }

  .filter-bar .quick-buttons {
    margin-left: 0;
    flex-wrap: wrap;
  }

  .kpi-section {
    grid-template-columns: repeat(2, 1fr);
    padding: 16px 20px;
    gap: 12px;
  }

  .kpi-card .kpi-value {
    font-size: 22px;
  }

  .charts-section {
    grid-template-columns: 1fr;
    padding: 0 20px 16px;
    gap: 12px;
  }

  .chart-container {
    min-height: 320px;
  }
}