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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: #f5f7fa;
  color: #333;
}

.container {
  display: flex;
  margin-top: 70px;
  min-height: calc(100vh - 140px);
}

main {
  flex: 1;
  margin-left: 250px;
  padding: 30px;
}

/* Page Sections */
.page-section {
  display: none;
}

.page-section.active {
  display: block;
}

/* Dashboard Header */
.dashboard-header {
  margin-bottom: 30px;
}

.dashboard-header h2 {
  font-size: 28px;
  color: #2c3e50;
  margin-bottom: 10px;
}

.dashboard-header p {
  color: #7f8c8d;
  font-size: 14px;
}

/* Cards Grid */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 25px;
  margin-bottom: 40px;
}

.card {
  background-color: #fff;
  border-radius: 10px;
  padding: 25px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
  transition: all 0.3s ease;
  border-top: 4px solid #667eea;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0,0,0,0.15);
}

.card i {
  font-size: 32px;
  color: #667eea;
  margin-bottom: 15px;
}

.card h3 {
  font-size: 18px;
  margin-bottom: 10px;
  color: #2c3e50;
}

.card p {
  color: #7f8c8d;
  font-size: 13px;
  margin-bottom: 15px;
  line-height: 1.5;
}

.card a,
.card button {
  display: inline-block;
  padding: 10px 20px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  text-decoration: none;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  transition: all 0.3s ease;
  border: none;
  cursor: pointer;
}

.card a:hover,
.card button:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

/* Stats Section */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 40px;
}

.stat-box {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: #fff;
  padding: 25px;
  border-radius: 10px;
  text-align: center;
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.stat-box h4 {
  font-size: 12px;
  text-transform: uppercase;
  opacity: 0.9;
  margin-bottom: 10px;
  font-weight: 600;
}

.stat-box .number {
  font-size: 32px;
  font-weight: 700;
}

/* Responsive Design */
@media (max-width: 768px) {
  .container {
    flex-direction: column;
  }

  main {
    margin-left: 200px;
    padding: 20px;
  }

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

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

@media (max-width: 600px) {
  main {
    margin-left: 150px;
    padding: 15px;
  }

  .dashboard-header h2 {
    font-size: 20px;
  }

  .cards {
    gap: 15px;
  }

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