:root {
  --primary: #2563eb;
  --primary-dark: #1e40af;
  --secondary: #10b981;
  --danger: #ef4444;
  --warning: #f59e0b;
  --dark: #1f2937;
  --light: #f9fafb;
  --border: #e5e7eb;
}

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background: var(--light);
  color: var(--dark);
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

/* Navbar */
.navbar {
  background: white;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  padding: 1rem 0;
  margin-bottom: 2rem;
}

.navbar-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.navbar-brand {
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--primary);
  text-decoration: none;
}

.navbar-menu {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.navbar-menu a {
  color: var(--dark);
  text-decoration: none;
  transition: color 0.3s;
}

.navbar-menu a:hover {
  color: var(--primary);
}

/* Cards */
.card {
  background: white;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
  margin-bottom: 1.5rem;
}

.card-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--dark);
}

/* Grid */
.grid {
  display: grid;
  gap: 1.5rem;
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* Stats */
.stat-card {
  background: white;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
  border-left: 4px solid var(--primary);
}

.stat-value {
  font-size: 2rem;
  font-weight: bold;
  color: var(--primary);
}

.stat-label {
  color: #6b7280;
  font-size: 0.875rem;
  margin-top: 0.5rem;
}

/* Forms */
.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--dark);
}

.form-control {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-size: 1rem;
  transition: border-color 0.3s;
}

.form-control:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 6px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.3s;
}

.btn-primary {
  background: var(--primary);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
}

.btn-success {
  background: var(--secondary);
  color: white;
}

.btn-danger {
  background: var(--danger);
  color: white;
}

.btn-sm {
  padding: 0.5rem 1rem;
  font-size: 0.875rem;
}

/* Table */
.table {
  width: 100%;
  border-collapse: collapse;
  background: white;
}

.table th,
.table td {
  padding: 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.table th {
  background: var(--light);
  font-weight: 600;
  color: var(--dark);
}

.table tr:hover {
  background: var(--light);
}

/* Alerts */
.alert {
  padding: 1rem 1.5rem;
  border-radius: 6px;
  margin-bottom: 1.5rem;
}

.alert-success {
  background: #d1fae5;
  color: #065f46;
  border-left: 4px solid var(--secondary);
}

.alert-error {
  background: #fee2e2;
  color: #991b1b;
  border-left: 4px solid var(--danger);
}

/* Login Page */
.login-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
}

.login-card {
  background: white;
  border-radius: 12px;
  padding: 3rem;
  width: 100%;
  max-width: 400px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
}

.login-title {
  text-align: center;
  font-size: 2rem;
  margin-bottom: 2rem;
  color: var(--dark);
}

/* Badge */
.badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: 0.75rem;
  font-weight: 600;
}

.badge-success {
  background: #d1fae5;
  color: #065f46;
}

.badge-warning {
  background: #fef3c7;
  color: #92400e;
}

.badge-danger {
  background: #fee2e2;
  color: #991b1b;
}

/* Progress Bar */
.progress {
  background: var(--border);
  border-radius: 12px;
  height: 8px;
  overflow: hidden;
  margin: 0.5rem 0;
}

.progress-bar {
  background: var(--primary);
  height: 100%;
  transition: width 0.3s;
}

/* Responsive */
@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  
  .navbar-menu {
    flex-direction: column;
    gap: 1rem;
  }
}