:root {
    --primary-color: #4f46e5;
    --secondary-color: #06b6d4;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --dark-bg: #1f2937;
    --dark-card: #374151;
    --light-bg: #f9fafb;
    --light-card: #ffffff;
    --text-dark: #111827;
    --text-light: #f9fafb;
    --border-light: #e5e7eb;
    --border-dark: #4b5563;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--light-bg);
    color: var(--text-dark);
    transition: all 0.3s ease;
}

body.dark {
    background: var(--dark-bg);
    color: var(--text-light);
}

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

/* Header */
.header {
    background: var(--light-card);
    border-bottom: 1px solid var(--border-light);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    transition: all 0.3s ease;
}

.dark .header {
    background: var(--dark-card);
    border-bottom-color: var(--border-dark);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

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

.nav-menu a {
    text-decoration: none;
    color: inherit;
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    transition: all 0.3s ease;
}

.nav-menu a:hover {
    background: var(--primary-color);
    color: white;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.theme-toggle {
    background: none;
    border: 1px solid var(--border-light);
    padding: 0.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.dark .theme-toggle {
    border-color: var(--border-dark);
}

/* Cards */
.card {
    background: var(--light-card);
    border-radius: 1rem;
    padding: 1.5rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    border: 1px solid var(--border-light);
}

.dark .card {
    background: var(--dark-card);
    border-color: var(--border-dark);
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 0.5rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
    text-align: center;
}

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

.btn-primary:hover {
    background: #4338ca;
    transform: translateY(-1px);
}

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

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

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

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-light);
    border-radius: 0.5rem;
    background: var(--light-card);
    color: var(--text-dark);
    transition: all 0.3s ease;
}

.dark .form-control {
    border-color: var(--border-dark);
    background: var(--dark-card);
    color: var(--text-light);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* Dashboard Grid */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    text-align: center;
}

.stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

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

/* Tables */
.table-container {
    overflow-x: auto;
    border-radius: 0.5rem;
    border: 1px solid var(--border-light);
}

.dark .table-container {
    border-color: var(--border-dark);
}

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

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

.dark .table th,
.dark .table td {
    border-bottom-color: var(--border-dark);
}

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

.dark .table th {
    background: var(--dark-bg);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    z-index: 1000;
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--light-card);
    border-radius: 1rem;
    padding: 2rem;
    max-width: 500px;
    width: 90%;
}

.dark .modal-content {
    background: var(--dark-card);
}

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

.login-card {
    max-width: 400px;
    width: 100%;
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    color: inherit;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
}

/* Responsive */
@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: block;
    }
    
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--light-card);
        border-top: 1px solid var(--border-light);
        box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        z-index: 1000;
    }
    
    .dark .nav-menu {
        background: var(--dark-card);
        border-top-color: var(--border-dark);
    }
    
    .nav-menu.active {
        display: block;
    }
    
    .nav-menu ul {
        flex-direction: column;
        gap: 0;
        margin: 0;
        padding: 1rem 0;
    }
    
    .nav-menu li {
        width: 100%;
    }
    
    .nav-menu a {
        display: block;
        padding: 1rem 2rem;
        border-radius: 0;
        border-bottom: 1px solid var(--border-light);
    }
    
    .dark .nav-menu a {
        border-bottom-color: var(--border-dark);
    }
    
    .nav-menu a:hover {
        background: var(--primary-color);
        color: white;
    }
    
    .dashboard-grid {
        grid-template-columns: 1fr;
    }
    
    .header-content {
        position: relative;
    }
    
    .user-menu {
        flex-wrap: wrap;
        gap: 0.5rem;
    }
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in {
    animation: fadeIn 0.5s ease-out;
}

/* Progress Charts */
.chart-container {
    position: relative;
    height: 300px;
    margin: 1rem 0;
}

/* Status badges */
.badge {
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.875rem;
    font-weight: 500;
}

.badge-success {
    background: #dcfce7;
    color: #166534;
}

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

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

.dark .badge-success {
    background: #166534;
    color: #dcfce7;
}

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

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