:root {
    /* Colors */
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary: #64748b;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #06b6d4;
    
    /* Grays */
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

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

body {
    font-family: 'Vazir', sans-serif;
    background: var(--gray-50);
    color: var(--gray-900);
    font-size: 14px;
    line-height: 1.6;
    direction: rtl;
}

/* Loading Screen */
#loadingScreen {
    z-index: 9999;
}

/* App Container */
.app-container {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: white;
    border-left: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease;
    z-index: 40;
}

.sidebar-header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
}

.logo-section {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.user-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--gray-50);
    border-radius: var(--radius-md);
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
}

.sidebar-nav {
    flex: 1;
    padding: var(--spacing-md);
    overflow-y: auto;
}

.nav-section {
    margin-bottom: var(--spacing-xl);
}

.nav-section-title {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--gray-500);
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.nav-item {
    display: flex;
    align-items: center;
    padding: var(--spacing-sm) var(--spacing-md);
    margin-bottom: 0.25rem;
    border-radius: var(--radius-md);
    color: var(--gray-600);
    text-decoration: none;
    transition: all 0.2s ease;
    font-size: 0.875rem;
    position: relative;
}

.nav-item:hover {
    background: var(--gray-50);
    color: var(--gray-900);
}

.nav-item.active {
    background: var(--primary);
    color: white;
}

.nav-item.active::before {
    content: '';
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 70%;
    background: white;
    border-radius: 3px 0 0 3px;
}

.nav-item i {
    margin-left: var(--spacing-md);
    width: 1.25rem;
    text-align: center;
}

.sidebar-footer {
    padding: var(--spacing-md);
    border-top: 1px solid var(--gray-200);
}

.footer-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
}

.stat-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm);
    background: var(--gray-50);
    border-radius: var(--radius-md);
}

/* Main Content */
.main-content {
    flex: 1;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

/* Header */
.main-header {
    background: white;
    border-bottom: 1px solid var(--gray-200);
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-shadow: var(--shadow-sm);
    z-index: 30;
}

.header-left,
.header-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.search-box {
    position: relative;
    flex: 1;
    max-width: 400px;
}

.search-box input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md) var(--spacing-sm) 2.5rem;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    transition: all 0.2s ease;
}

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

.search-box i {
    position: absolute;
    right: var(--spacing-md);
    top: 50%;
    transform: translateY(-50%);
    color: var(--gray-400);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.action-btn {
    position: relative;
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--gray-600);
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.action-btn:hover {
    background: var(--gray-100);
    color: var(--gray-900);
}

.badge {
    position: absolute;
    top: 0;
    left: 0;
    background: var(--danger);
    color: white;
    font-size: 0.625rem;
    padding: 0.125rem 0.375rem;
    border-radius: 9999px;
    font-weight: 600;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
}

.user-menu:hover {
    background: var(--gray-100);
}

.user-details {
    text-align: right;
}

.user-name {
    font-weight: 500;
    font-size: 0.875rem;
}

.user-role {
    font-size: 0.75rem;
    color: var(--gray-500);
}

.dropdown-toggle {
    color: var(--gray-400);
    transition: transform 0.2s ease;
}

/* Main Content Body */
.main-content-body {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-lg);
}

/* Content Sections */
.content-section {
    display: none;
}

.content-section.active {
    display: block;
    animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Section Header */
.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-xl);
}

.section-header h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
}

.section-header p {
    color: var(--gray-600);
    font-size: 0.875rem;
}

.header-actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    white-space: nowrap;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--gray-200);
    color: var(--gray-700);
}

.btn-secondary:hover {
    background: var(--gray-300);
}

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

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

.btn-icon {
    padding: var(--spacing-sm);
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--gray-600);
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
}

.btn-icon:hover {
    background: var(--gray-100);
    color: var(--gray-900);
}

.btn-link {
    background: none;
    border: none;
    color: var(--primary);
    cursor: pointer;
    font-size: 0.875rem;
    padding: 0;
}

.btn-link:hover {
    text-decoration: underline;
}

/* Forms */
.form-input {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    transition: all 0.2s ease;
    background: white;
}

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

.form-input::placeholder {
    color: var(--gray-400);
}

/* Cards */
.card {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    transition: all 0.2s ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
}

/* Dashboard Stats */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    position: relative;
    overflow: hidden;
    transition: all 0.2s ease;
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 4px;
    height: 100%;
}

.stat-card.income::before { background: var(--success); }
.stat-card.sales::before { background: var(--primary); }
.stat-card.customers::before { background: var(--info); }
.stat-card.products::before { background: var(--warning); }

.stat-icon {
    width: 3rem;
    height: 3rem;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin-bottom: var(--spacing-md);
}

.stat-card.income .stat-icon { background: rgba(16, 185, 129, 0.1); color: var(--success); }
.stat-card.sales .stat-icon { background: rgba(37, 99, 235, 0.1); color: var(--primary); }
.stat-card.customers .stat-icon { background: rgba(6, 182, 212, 0.1); color: var(--info); }
.stat-card.products .stat-icon { background: rgba(245, 158, 11, 0.1); color: var(--warning); }

.stat-content h3 {
    font-size: 0.875rem;
    color: var(--gray-600);
    margin-bottom: var(--spacing-sm);
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: var(--spacing-sm);
}

.stat-change {
    font-size: 0.75rem;
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.stat-change.positive { color: var(--success); }
.stat-change.negative { color: var(--danger); }

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

.chart-card {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
}

.chart-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
}

.chart-header h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--gray-900);
}

.chart-filter {
    padding: var(--spacing-xs) var(--spacing-sm);
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    background: white;
}

.chart-container {
    position: relative;
    height: 250px;
}

/* Activities */
.activities-section {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
}

.activities-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.activity-item {
    display: flex;
    align-items: start;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    transition: all 0.2s ease;
}

.activity-item:hover {
    background: var(--gray-50);
}

.activity-icon {
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    flex-shrink: 0;
}

.activity-content {
    flex: 1;
}

.activity-title {
    font-weight: 500;
    color: var(--gray-900);
    margin-bottom: 0.25rem;
}

.activity-description {
    font-size: 0.875rem;
    color: var(--gray-600);
    margin-bottom: 0.25rem;
}

.activity-time {
    font-size: 0.75rem;
    color: var(--gray-500);
}

/* POS System */
.pos-container {
    display: grid;
    grid-template-columns: 1fr 400px;
    gap: var(--spacing-lg);
    height: calc(100vh - 200px);
}

.pos-products {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    display: flex;
    flex-direction: column;
}

.pos-search {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
}

.pos-search input {
    flex: 1;
}

.pos-categories {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
    overflow-x: auto;
    padding-bottom: var(--spacing-xs);
}

.category-btn {
    padding: var(--spacing-xs) var(--spacing-md);
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-full);
    background: white;
    color: var(--gray-600);
    font-size: 0.875rem;
    white-space: nowrap;
    cursor: pointer;
    transition: all 0.2s ease;
}

.category-btn:hover,
.category-btn.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.products-grid {
    flex: 1;
    overflow-y: auto;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: var(--spacing-md);
}

.product-card {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    cursor: pointer;
    transition: all 0.2s ease;
    text-align: center;
}

.product-card:hover {
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.product-image {
    width: 60px;
    height: 60px;
    margin: 0 auto var(--spacing-sm);
    background: var(--gray-200);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--gray-600);
}

.product-name {
    font-weight: 500;
    color: var(--gray-900);
    margin-bottom: 0.25rem;
    font-size: 0.875rem;
}

.product-price {
    color: var(--primary);
    font-weight: 600;
}

.product-stock {
    font-size: 0.75rem;
    color: var(--gray-500);
    margin-top: 0.25rem;
}

.pos-right {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.pos-receipt {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.receipt-header {
    text-align: center;
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 2px dashed var(--gray-200);
}

.receipt-header h3 {
    font-size: 1.25rem;
    color: var(--gray-900);
    margin-bottom: var(--spacing-sm);
}

.receipt-header p {
    font-size: 0.875rem;
    color: var(--gray-600);
}

.receipt-customer {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-lg);
}

.receipt-items {
    flex: 1;
    overflow-y: auto;
    margin-bottom: var(--spacing-lg);
}

.receipt-item {
    display: flex;
    justify-content: space-between;
    align-items: start;
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--gray-100);
}

.receipt-item:last-child {
    border-bottom: none;
}

.receipt-item-info {
    flex: 1;
}

.receipt-item-name {
    font-weight: 500;
    color: var(--gray-900);
}

.receipt-item-details {
    font-size: 0.75rem;
    color: var(--gray-500);
}

.receipt-item-price {
    text-align: left;
    font-weight: 500;
    color: var(--gray-900);
}

.empty-receipt {
    text-align: center;
    padding: var(--spacing-2xl);
    color: var(--gray-400);
}

.empty-receipt i {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.receipt-summary {
    border-top: 2px dashed var(--gray-200);
    padding-top: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.summary-row {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--spacing-sm);
}

.summary-row.total {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--gray-900);
    padding-top: var(--spacing-sm);
    border-top: 1px solid var(--gray-200);
}

.receipt-payment {
    margin-bottom: var(--spacing-lg);
}

.payment-methods {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.payment-method {
    padding: var(--spacing-sm);
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md);
    background: white;
    color: var(--gray-600);
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.payment-method:hover,
.payment-method.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.payment-input {
    margin-bottom: var(--spacing-md);
}

.payment-input label {
    display: block;
    font-size: 0.875rem;
    color: var(--gray-700);
    margin-bottom: var(--spacing-xs);
}

.change-amount {
    text-align: center;
    padding: var(--spacing-md);
    background: var(--gray-50);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
}

.change-amount span:first-child {
    color: var(--gray-600);
}

.change-amount span:last-child {
    font-weight: 600;
    color: var(--success);
}

.receipt-actions {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-sm);
}

/* Modals */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
}

.modal.show {
    display: flex;
}

.modal-content {
    background: white;
    border-radius: var(--radius-xl);
    max-width: 600px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--gray-200);
}

.modal-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--gray-900);
}

.close-btn {
    width: 2rem;
    height: 2rem;
    border-radius: var(--radius-md);
    background: transparent;
    color: var(--gray-400);
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.close-btn:hover {
    background: var(--gray-100);
    color: var(--gray-600);
}

/* Calculator */
.calculator {
    background: var(--gray-800);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    max-width: 300px;
    width: 100%;
}

.calc-display {
    margin-bottom: var(--spacing-md);
}

.calc-display input {
    width: 100%;
    padding: var(--spacing-md);
    background: var(--gray-900);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1.25rem;
    text-align: left;
}

.calc-buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-sm);
}

.calc-btn {
    padding: var(--spacing-md);
    background: var(--gray-700);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.calc-btn:hover {
    background: var(--gray-600);
}

.calc-btn.operator {
    background: var(--primary);
}

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

.calc-btn.equals {
    background: var(--success);
}

.calc-btn.equals:hover {
    background: #059669;
}

/* Toast Notifications */
#toastContainer {
    z-index: 2000;
}

.toast {
    background: var(--gray-800);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    min-width: 300px;
    animation: slideIn 0.3s ease-out;
    box-shadow: var(--shadow-lg);
}

.toast.success {
    background: var(--success);
}

.toast.error {
    background: var(--danger);
}

.toast.warning {
    background: var(--warning);
}

.toast.info {
    background: var(--info);
}

@keyframes slideIn {
    from {
        transform: translateX(-100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    position: fixed;
    top: var(--spacing-md);
    right: var(--spacing-md);
    z-index: 1001;
    background: white;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md);
    padding: var(--spacing-sm);
    cursor: pointer;
    box-shadow: var(--shadow-md);
    color: var(--gray-600);
}

/* Responsive */
@media (max-width: 1024px) {
    .sidebar {
        position: fixed;
        right: 0;
        top: 0;
        height: 100%;
        transform: translateX(100%);
        box-shadow: var(--shadow-xl);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-right: 0;
    }
    
    .pos-container {
        grid-template-columns: 1fr;
    }
    
    .pos-right {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        background: white;
        border-top: 1px solid var(--gray-200);
        border-radius: var(--radius-xl) var(--radius-xl) 0 0;
        max-height: 50vh;
        z-index: 50;
    }
}

@media (max-width: 768px) {
    .mobile-menu-btn {
        display: block;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .charts-row {
        grid-template-columns: 1fr;
    }
    
    .header-left,
    .header-right {
        gap: var(--spacing-sm);
    }
    
    .search-box {
        max-width: 200px;
    }
    
    .user-details {
        display: none;
    }
    
    .products-grid {
        grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
    }
    
    .modal-content {
        margin: var(--spacing-md);
    }
}

/* Utilities */
.text-right { text-align: right; }
.text-left { text-align: left; }
.text-center { text-align: center; }

.hidden { display: none; }
.block { display: block; }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: 0.5rem; }
.gap-4 { gap: 1rem; }

.mb-2 { margin-bottom: 0.5rem; }
.mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; }

.p-2 { padding: 0.5rem; }
.p-4 { padding: 1rem; }
.p-6 { padding: 1.5rem; }

.rounded { border-radius: 0.25rem; }
.rounded-lg { border-radius: 0.5rem; }

.shadow { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }

/* Loading Spinner */
.spinner {
    border: 3px solid var(--gray-200);
    border-top: 3px solid var(--primary);
    border-radius: 50%;
    width: 1.5rem;
    height: 1.5rem;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-400);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-500);
}