:root {
  --sidebar-bg: #1e2a3b;
  --sidebar-width: 260px;
  --accent-color: #0d6efd;
}

body {
  background-color: #f8f9fa;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

#sidebar {
  width: var(--sidebar-width);
  height: 100vh;
  position: fixed;
  top: 0;
  left: 0;
  background-color: var(--sidebar-bg);
  color: #fff;
  z-index: 1000;
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
}

#sidebar .brand {
  padding: 1.5rem;
  font-size: 1.25rem;
  font-weight: 700;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

#sidebar .nav {
  flex-grow: 1;
  overflow-y: auto;
  padding: 1rem 0;
}

#sidebar .nav-link {
  color: rgba(255,255,255,0.7);
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: center;
  transition: all 0.2s;
}

#sidebar .nav-link:hover, #sidebar .nav-link.active {
  color: #fff;
  background-color: rgba(255,255,255,0.05);
}

#sidebar .nav-link.active {
  border-left: 4px solid var(--accent-color);
}

#sidebar .nav-link i {
  width: 30px;
  font-size: 1.1rem;
}

#sidebar .user-info {
  padding: 1rem 1.5rem;
  border-top: 1px solid rgba(255,255,255,0.1);
  font-size: 0.875rem;
}

#main-content {
  margin-left: var(--sidebar-width);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

#topnav {
  background-color: #fff;
  box-shadow: 0 0.125rem 0.25rem rgba(0,0,0,0.075);
  padding: 1rem 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.content-wrapper {
  padding: 1.5rem;
  flex-grow: 1;
}

.stat-card {
  border: none;
  border-radius: 1rem;
  box-shadow: 0 0.125rem 0.25rem rgba(0,0,0,0.075);
  border-left: 4px solid var(--accent-color);
  transition: transform 0.2s;
  background: #fff;
}

.stat-card:hover {
  transform: translateY(-2px);
}

.stat-card.primary { border-left-color: #0d6efd; }
.stat-card.success { border-left-color: #198754; }
.stat-card.warning { border-left-color: #ffc107; }
.stat-card.danger { border-left-color: #dc3545; }
.stat-card.info { border-left-color: #0dcaf0; }

.badge-pill {
  border-radius: 50rem;
  padding: 0.35em 0.65em;
}

.table-hover tbody tr:hover {
  background-color: rgba(0,0,0,0.02);
}

.card {
  border: none;
  box-shadow: 0 0.125rem 0.25rem rgba(0,0,0,0.075);
  border-radius: 0.75rem;
}

@media (max-width: 768px) {
  #sidebar {
    margin-left: calc(var(--sidebar-width) * -1);
  }
  #sidebar.show {
    margin-left: 0;
  }
  #main-content {
    margin-left: 0;
  }
}