:root {
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --secondary-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --info-color: #3b82f6;
    --success-color: #10b981;
    
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-dark: #1e293b;
    
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-light: #94a3b8;
    
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    
    --sidebar-width: 260px;
    --topbar-height: 70px;
    
    --transition-speed: 0.3s;
}

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

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

/* Sidebar */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: linear-gradient(180deg, #1e3a8a 0%, #1e40af 100%);
    color: white;
    padding: 20px;
    z-index: 1000;
    transition: transform var(--transition-speed);
    overflow-y: auto;
}

.sidebar-header {
    text-align: center;
    padding: 20px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    margin-bottom: 30px;
}

.sidebar-header i {
    font-size: 3rem;
    margin-bottom: 10px;
    color: #60a5fa;
}

.sidebar-header h2 {
    font-size: 1.2rem;
    font-weight: 600;
    line-height: 1.3;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 12px 15px;
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    border-radius: 8px;
    transition: all var(--transition-speed);
    font-size: 0.95rem;
}

.nav-item:hover {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    transform: translateX(5px);
}

.nav-item.active {
    background: rgba(255, 255, 255, 0.15);
    color: white;
    font-weight: 600;
}

.nav-item i {
    font-size: 1.2rem;
    width: 20px;
}

.sidebar-footer {
    position: absolute;
    bottom: 20px;
    left: 20px;
    right: 20px;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.user-info i {
    font-size: 2.5rem;
    color: #60a5fa;
}

.user-name {
    font-weight: 600;
    font-size: 0.95rem;
}

.user-role {
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.7);
}

/* Main Content */
.main-content {
    margin-left: var(--sidebar-width);
    min-height: 100vh;
    transition: margin-left var(--transition-speed);
}

/* Topbar */
.topbar {
    height: var(--topbar-height);
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 0 30px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-primary);
    cursor: pointer;
}

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

.topbar-actions {
    display: flex;
    gap: 10px;
}

.btn-icon {
    position: relative;
    width: 40px;
    height: 40px;
    border: none;
    background: var(--bg-primary);
    border-radius: 8px;
    cursor: pointer;
    transition: all var(--transition-speed);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    color: var(--text-secondary);
}

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

.btn-icon .badge {
    position: absolute;
    top: -5px;
    right: -5px;
    background: var(--danger-color);
    color: white;
    font-size: 0.7rem;
    padding: 2px 6px;
    border-radius: 10px;
    font-weight: 600;
}

/* Content Wrapper */
.content-wrapper {
    padding: 30px;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    padding: 25px;
    display: flex;
    align-items: center;
    gap: 20px;
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-speed);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
    color: white;
}

.stat-icon.bg-blue { background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%); }
.stat-icon.bg-green { background: linear-gradient(135deg, #10b981 0%, #059669 100%); }
.stat-icon.bg-orange { background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%); }
.stat-icon.bg-purple { background: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%); }

.stat-info h3 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 5px;
}

.stat-info p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Charts Row */
.charts-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

/* Card */
.card, .chart-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

.card-header {
    padding: 20px 25px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-header h3 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.card-body {
    padding: 25px;
}

/* Table */
.table-responsive {
    overflow-x: auto;
}

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

.table thead th {
    padding: 12px 15px;
    text-align: left;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-bottom: 2px solid var(--border-color);
}

.table tbody td {
    padding: 15px;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-primary);
}

.table tbody tr:hover {
    background: var(--bg-primary);
}

/* Buttons */
.btn {
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    transition: all var(--transition-speed);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

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

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

.btn-sm {
    padding: 6px 12px;
    font-size: 0.85rem;
}

/* Badge/Status */
.badge {
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
    display: inline-block;
}

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

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

.badge-info {
    background: #dbeafe;
    color: #1e40af;
}

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

/* Loading */
.loading {
    text-align: center;
    padding: 40px;
    color: var(--text-secondary);
}

.loading i {
    font-size: 2rem;
    margin-bottom: 10px;
}

/* Text utilities */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-primary { color: var(--primary-color); }
.text-success { color: var(--success-color); }
.text-danger { color: var(--danger-color); }

/* Products Grid */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 20px;
}

.product-card {
    background: var(--bg-secondary);
    border-radius: 12px;
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: all var(--transition-speed);
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.product-card-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 20px;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.product-icon {
    width: 60px;
    height: 60px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: white;
}

.product-badge {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
}

.product-card-body {
    padding: 20px;
}

.product-card-body h3 {
    font-size: 1.2rem;
    margin-bottom: 5px;
    color: var(--text-primary);
}

.product-code {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
}

.product-category {
    display: inline-block;
    padding: 4px 12px;
    background: var(--bg-primary);
    border-radius: 20px;
    font-size: 0.85rem;
    color: var(--primary-color);
    margin-bottom: 10px;
}

.product-description {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 10px 0;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.product-meta {
    display: flex;
    gap: 15px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-top: 10px;
}

.product-meta span {
    display: flex;
    align-items: center;
    gap: 5px;
}

.product-card-footer {
    padding: 15px 20px;
    border-top: 1px solid var(--border-color);
    display: flex;
    gap: 10px;
    align-items: center;
}

.product-card-footer .btn {
    flex: 1;
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.active {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .menu-toggle {
        display: block;
    }
    
    .charts-row {
        grid-template-columns: 1fr;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .products-grid {
        grid-template-columns: 1fr;
    }
}