/* Root Variables */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #8b5cf6;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
    --info: #3b82f6;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --text-primary: #111827;
    --text-secondary: #6b7280;
    --text-tertiary: #9ca3af;
    
    --border: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    --sidebar-width: 260px;
    --header-height: 70px;
    --border-radius: 12px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode Variables */
body.dark-mode {
    --bg-primary: #111827;
    --bg-secondary: #1f2937;
    --bg-tertiary: #374151;
    --text-primary: #f9fafb;
    --text-secondary: #d1d5db;
    --text-tertiary: #9ca3af;
    --border: #374151;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Sidebar */
.sidebar {
    position: fixed;
    left: 0;
    top: 0;
    width: var(--sidebar-width);
    height: 100vh;
    background: var(--bg-primary);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    z-index: 1000;
    transition: var(--transition);
}

.sidebar-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary);
}

.logo i {
    font-size: 1.75rem;
}

.sidebar-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 8px;
    transition: var(--transition);
}

.sidebar-toggle:hover {
    background: var(--bg-tertiary);
}

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

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--border-radius);
    transition: var(--transition);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.nav-item:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.nav-item.active {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    box-shadow: var(--shadow-md);
}

.nav-item i {
    font-size: 1.25rem;
    width: 24px;
    text-align: center;
}

.sidebar-footer {
    padding: 1rem;
    border-top: 1px solid var(--border);
}

.theme-toggle {
    width: 100%;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.875rem 1rem;
    background: var(--bg-secondary);
    border: none;
    border-radius: var(--border-radius);
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.theme-toggle:hover {
    background: var(--bg-tertiary);
}

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

/* Header */
.header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border);
    padding: 1.25rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 8px;
    transition: var(--transition);
}

.mobile-menu-btn:hover {
    background: var(--bg-secondary);
}

.page-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
}

.header-right {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.header-date {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Pages */
.page {
    display: none;
    padding: 2rem;
    animation: fadeIn 0.3s ease-in-out;
}

.page.active {
    display: block;
}

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

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

.stat-card {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    display: flex;
    align-items: center;
    gap: 1.25rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border);
}

.stat-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
}

.stat-card.primary .stat-icon {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
}

.stat-card.success .stat-icon {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

.stat-card.warning .stat-icon {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

.stat-card.info .stat-icon {
    background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
}

.stat-content {
    flex: 1;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 0.25rem;
    font-weight: 500;
}

.stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.stat-change {
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

/* Charts */
.charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(450px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.chart-card {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border);
}

.chart-card.full-width {
    grid-column: 1 / -1;
}

.chart-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.5rem;
}

.chart-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.chart-filter {
    padding: 0.5rem 1rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.chart-filter:focus {
    outline: none;
    border-color: var(--primary);
}

.chart-container {
    position: relative;
}

/* Card */
.card {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
    border: 1px solid var(--border);
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.5rem;
}

.card-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.view-all-link {
    color: var(--primary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.view-all-link:hover {
    color: var(--primary-dark);
}

/* Transactions List */
.transactions-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.transaction-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 10px;
    transition: var(--transition);
}

.transaction-item:hover {
    background: var(--bg-tertiary);
}

.transaction-left {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.transaction-icon {
    width: 45px;
    height: 45px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
}

.transaction-details h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.transaction-details p {
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.transaction-amount {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--danger);
}

.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-secondary);
}

.empty-state i {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

/* Page Actions */
.page-actions {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 10px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    color: white;
    box-shadow: var(--shadow);
}

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

.btn-secondary {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--bg-tertiary);
}

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

.btn-danger:hover {
    background: #dc2626;
}

/* Filters */
.filters-card {
    margin-bottom: 1.5rem;
}

.filters-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.filter-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.filter-group label {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.filter-input {
    padding: 0.75rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 0.95rem;
    transition: var(--transition);
}

.filter-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

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

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

.expenses-table thead {
    background: var(--bg-secondary);
}

.expenses-table th {
    padding: 1rem;
    text-align: left;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.expenses-table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border);
}

.expenses-table tbody tr {
    transition: var(--transition);
}

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

.category-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.375rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 600;
}

.action-btns {
    display: flex;
    gap: 0.5rem;
}

.action-btn {
    padding: 0.5rem;
    border: none;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition);
}

.action-btn:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.action-btn.edit:hover {
    color: var(--primary);
}

.action-btn.delete:hover {
    color: var(--danger);
}

/* Pagination */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-top: 1.5rem;
}

.page-btn {
    padding: 0.5rem 0.875rem;
    border: 1px solid var(--border);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.page-btn:hover {
    background: var(--bg-tertiary);
}

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

.page-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Budget */
.budget-overview {
    padding: 1rem 0;
}

.budget-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

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

.budget-stat-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    font-weight: 500;
}

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

.budget-stat-value.success {
    color: var(--success);
}

.budget-stat-value.danger {
    color: var(--danger);
}

.budget-progress {
    margin-top: 1rem;
}

.progress-bar {
    width: 100%;
    height: 12px;
    background: var(--bg-tertiary);
    border-radius: 20px;
    overflow: hidden;
    margin-bottom: 0.5rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--success) 0%, var(--primary) 100%);
    transition: width 0.5s ease;
    border-radius: 20px;
}

.progress-fill.warning {
    background: linear-gradient(90deg, var(--warning) 0%, var(--danger) 100%);
}

.progress-text {
    text-align: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.category-budgets {
    display: grid;
    gap: 1rem;
}

.category-budget-item {
    padding: 1rem;
    background: var(--bg-secondary);
    border-radius: 10px;
}

.category-budget-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.75rem;
}

.category-budget-header h4 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.category-budget-amount {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
}

.category-budget-amount span {
    color: var(--text-secondary);
}

.category-budget-amount .spent {
    color: var(--danger);
    font-weight: 600;
}

.category-budget-amount .budget {
    color: var(--text-primary);
    font-weight: 600;
}

/* Insights */
.insights-grid {
    display: grid;
    gap: 1rem;
}

.insight-item {
    padding: 1.25rem;
    background: var(--bg-secondary);
    border-radius: 10px;
    border-left: 4px solid var(--primary);
}

.insight-item h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.insight-item p {
    font-size: 0.875rem;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    padding: 1rem;
    overflow-y: auto;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s ease;
}

.modal-content {
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    width: 100%;
    max-width: 500px;
    box-shadow: var(--shadow-xl);
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.modal-header h2 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.modal-close {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 6px;
    transition: var(--transition);
    font-size: 1.25rem;
}

.modal-close:hover {
    background: var(--bg-secondary);
    color: var(--text-primary);
}

/* Form */
form {
    padding: 1.5rem;
}

.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.form-input {
    width: 100%;
    padding: 0.875rem;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-family: inherit;
    transition: var(--transition);
}

.form-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

textarea.form-input {
    resize: vertical;
    min-height: 80px;
}

.form-actions {
    display: flex;
    gap: 1rem;
    justify-content: flex-end;
    margin-top: 1.5rem;
}

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background: var(--bg-primary);
    padding: 1rem 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-xl);
    z-index: 3000;
    transform: translateX(400px);
    transition: transform 0.3s ease;
    border: 1px solid var(--border);
}

.toast.show {
    transform: translateX(0);
}

.toast-content {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.toast-icon {
    font-size: 1.25rem;
}

.toast.success .toast-icon {
    color: var(--success);
}

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

.toast.info .toast-icon {
    color: var(--info);
}

.toast-message {
    font-weight: 500;
    color: var(--text-primary);
}

/* Category Colors */
.category-Food { background: #fef3c7; color: #92400e; }
.category-Transport { background: #dbeafe; color: #1e3a8a; }
.category-Shopping { background: #fce7f3; color: #831843; }
.category-Bills { background: #fee2e2; color: #991b1b; }
.category-Entertainment { background: #ede9fe; color: #5b21b6; }
.category-Healthcare { background: #d1fae5; color: #065f46; }
.category-Education { background: #e0e7ff; color: #3730a3; }
.category-Others { background: #f3f4f6; color: #374151; }

body.dark-mode .category-Food { background: #78350f; color: #fef3c7; }
body.dark-mode .category-Transport { background: #1e3a8a; color: #dbeafe; }
body.dark-mode .category-Shopping { background: #831843; color: #fce7f3; }
body.dark-mode .category-Bills { background: #991b1b; color: #fee2e2; }
body.dark-mode .category-Entertainment { background: #5b21b6; color: #ede9fe; }
body.dark-mode .category-Healthcare { background: #065f46; color: #d1fae5; }
body.dark-mode .category-Education { background: #3730a3; color: #e0e7ff; }
body.dark-mode .category-Others { background: #374151; color: #f3f4f6; }

/* Responsive */
@media (max-width: 1024px) {
    .charts-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    :root {
        --sidebar-width: 0;
    }
    
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.active {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .header {
        padding: 1rem;
    }
    
    .page-title {
        font-size: 1.25rem;
    }
    
    .page {
        padding: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .charts-grid {
        grid-template-columns: 1fr;
    }
    
    .filters-grid {
        grid-template-columns: 1fr;
    }
    
    .table-container {
        overflow-x: scroll;
    }
    
    .expenses-table {
        min-width: 600px;
    }
    
    .toast {
        right: 1rem;
        left: 1rem;
        bottom: 1rem;
    }
}

@media (max-width: 480px) {
    .stat-card {
        flex-direction: column;
        text-align: center;
    }
    
    .transaction-item {
        flex-direction: column;
        gap: 0.75rem;
        text-align: center;
    }
    
    .transaction-left {
        flex-direction: column;
    }
}