/* ============================================
   BUDGET TRACKER - STYLES
   Mobile-first responsive design with dark mode
   ============================================ */

/* ============================================
   CSS VARIABLES
   ============================================ */
:root {
    /* Light Mode Colors */
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --income-color: #10b981;
    --expense-color: #ef4444;
    --transfer-color: #3b82f6;
    
    /* Background Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #e2e8f0;
    
    /* Text Colors */
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    /* Border & Shadow */
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    
    /* Layout */
    --header-height: 70px;
    --nav-height: 50px;
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

/* Dark Mode Variables */
body.dark-mode {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --bg-primary: #1e293b;
    --bg-secondary: #0f172a;
    --bg-tertiary: #334155;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --border-color: #334155;
}

/* ============================================
   RESET & BASE STYLES
   ============================================ */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

/* ============================================
   LAYOUT
   ============================================ */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header */
.app-header {
    background-color: var(--bg-primary);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--header-height);
}

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

.header-content h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.header-actions {
    display: flex;
    gap: 0.5rem;
}

/* Navigation */
.main-nav {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: var(--header-height);
    z-index: 99;
}

.nav-tabs {
    display: flex;
    list-style: none;
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.nav-tabs::-webkit-scrollbar {
    display: none;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 1.5rem;
    color: var(--text-secondary);
    text-decoration: none;
    border-bottom: 3px solid transparent;
    transition: var(--transition);
    white-space: nowrap;
    font-size: 0.95rem;
}

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

.nav-link.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
    font-weight: 600;
}

/* Main Content */
.main-content {
    padding: 2rem 0;
    min-height: calc(100vh - var(--header-height) - var(--nav-height));
}

.tab-content {
    display: none;
}

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

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

/* ============================================
   CARDS
   ============================================ */
.card {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-sm);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    transition: var(--transition);
}

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

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

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

.card h3 {
    color: var(--text-primary);
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

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

.summary-card {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1.5rem;
    position: relative;
    overflow: hidden;
}

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

.income-card::before {
    background-color: var(--income-color);
}

.expense-card::before {
    background-color: var(--expense-color);
}

.savings-card::before {
    background-color: var(--primary-color);
}

.budget-card::before {
    background-color: var(--warning-color);
}

.card-icon {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
}

.income-card .card-icon {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--income-color);
}

.expense-card .card-icon {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--expense-color);
}

.savings-card .card-icon {
    background-color: rgba(79, 70, 229, 0.1);
    color: var(--primary-color);
}

.budget-card .card-icon {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

.card-content h3 {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
    margin-bottom: 0.5rem;
}

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

.card-content .period {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Charts Grid */
.charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

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

/* ============================================
   TRANSACTIONS
   ============================================ */
.transaction-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.transaction-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
    border-left: 4px solid var(--border-color);
    transition: var(--transition);
    cursor: pointer;
}

.transaction-item:hover {
    background-color: var(--bg-tertiary);
    transform: translateX(4px);
}

.transaction-item.income {
    border-left-color: var(--income-color);
}

.transaction-item.expense {
    border-left-color: var(--expense-color);
}

.transaction-item.transfer {
    border-left-color: var(--transfer-color);
}

.transaction-info {
    flex: 1;
}

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

.transaction-description {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.transaction-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 0.25rem;
}

.transaction-amount {
    font-size: 1.25rem;
    font-weight: 700;
    white-space: nowrap;
}

.transaction-amount.income {
    color: var(--income-color);
}

.transaction-amount.expense {
    color: var(--expense-color);
}

.transaction-amount.transfer {
    color: var(--transfer-color);
}

.transaction-actions {
    display: flex;
    gap: 0.5rem;
    margin-left: 1rem;
}

/* Filters */
.filters {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
    padding: 1rem;
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
}

.search-input,
.filter-select,
.date-input {
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.875rem;
    transition: var(--transition);
}

.search-input {
    flex: 1;
    min-width: 200px;
}

.search-input:focus,
.filter-select:focus,
.date-input:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.1);
}

/* ============================================
   ACCOUNTS
   ============================================ */
.accounts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
}

.account-card {
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    border-top: 4px solid var(--primary-color);
    transition: var(--transition);
    cursor: pointer;
}

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

.account-header {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: 1rem;
}

.account-name {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-primary);
}

.account-type {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.account-balance {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-top: 0.5rem;
}

.account-actions {
    display: flex;
    gap: 0.5rem;
}

/* ============================================
   BUDGETS
   ============================================ */
.budgets-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.budget-item {
    background-color: var(--bg-secondary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    transition: var(--transition);
}

.budget-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.budget-category {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.budget-amount {
    font-size: 1rem;
    color: var(--text-secondary);
}

.budget-progress {
    margin-top: 0.75rem;
}

.progress-bar {
    width: 100%;
    height: 12px;
    background-color: var(--bg-tertiary);
    border-radius: 6px;
    overflow: hidden;
    position: relative;
}

.progress-fill {
    height: 100%;
    background-color: var(--success-color);
    transition: width 0.5s ease, background-color 0.3s ease;
    border-radius: 6px;
}

.progress-fill.warning {
    background-color: var(--warning-color);
}

.progress-fill.danger {
    background-color: var(--danger-color);
}

.budget-status {
    display: flex;
    justify-content: space-between;
    margin-top: 0.5rem;
    font-size: 0.875rem;
}

.status-text {
    color: var(--text-secondary);
}

.status-percentage {
    font-weight: 600;
}

.status-percentage.success {
    color: var(--success-color);
}

.status-percentage.warning {
    color: var(--warning-color);
}

.status-percentage.danger {
    color: var(--danger-color);
}

/* ============================================
   FORECAST
   ============================================ */
.forecast-disclaimer {
    padding: 1rem;
    background-color: rgba(59, 130, 246, 0.1);
    border-left: 4px solid var(--transfer-color);
    border-radius: var(--border-radius);
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-bottom: 1rem;
}

.forecast-controls {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.forecast-summary {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 1.5rem;
}

.forecast-card {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
}

.forecast-card h4 {
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

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

/* ============================================
   BUTTONS
   ============================================ */
.btn {
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    white-space: nowrap;
}

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

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

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

.btn-secondary:hover {
    background-color: #475569;
}

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

.btn-success:hover {
    background-color: #059669;
}

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

.btn-warning:hover {
    background-color: #d97706;
}

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

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

.icon-btn {
    width: 40px;
    height: 40px;
    border: none;
    background-color: transparent;
    color: var(--text-secondary);
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.125rem;
}

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

.btn-small {
    padding: 0.375rem 0.75rem;
    font-size: 0.75rem;
}

/* ============================================
   MODALS
   ============================================ */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    backdrop-filter: blur(4px);
    animation: fadeIn 0.3s ease;
}

.modal.active {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 1rem;
}

.modal-content {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    width: 100%;
    max-width: 500px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from { opacity: 0; transform: translateY(50px); }
    to { opacity: 1; transform: translateY(0); }
}

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

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

.modal-close {
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--text-secondary);
    cursor: pointer;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: var(--transition);
}

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

.modal form {
    padding: 1.5rem;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

/* ============================================
   FORMS
   ============================================ */
.form-group {
    margin-bottom: 1.25rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-primary);
    font-size: 0.875rem;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.625rem 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    font-size: 0.875rem;
    font-family: inherit;
    transition: var(--transition);
}

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

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

.checkbox-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
    cursor: pointer;
}

/* ============================================
   CAMERA & RECEIPT
   ============================================ */
.camera-container {
    padding: 1.5rem;
}

#cameraVideo {
    width: 100%;
    border-radius: var(--border-radius);
    background-color: var(--bg-secondary);
}

#capturedImagePreview img {
    width: 100%;
    border-radius: var(--border-radius);
    margin-top: 1rem;
}

.receipt-actions {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

#receiptPreview img {
    width: 100%;
    max-width: 200px;
    border-radius: var(--border-radius);
    margin-top: 0.5rem;
    border: 2px solid var(--border-color);
}

/* ============================================
   EXPORT OPTIONS
   ============================================ */
.export-options {
    padding: 1.5rem;
}

.export-section {
    margin-bottom: 2rem;
}

.export-section h3 {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.export-section .btn {
    display: block;
    width: 100%;
    margin-bottom: 0.75rem;
}

.file-input-wrapper {
    position: relative;
}

.file-input-wrapper input[type="file"] {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

.file-input-wrapper .btn {
    width: 100%;
}

/* ============================================
   SETTINGS
   ============================================ */
.settings-content {
    padding: 1.5rem;
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.text-center {
    text-align: center;
}

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.hidden {
    display: none !important;
}

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

.empty-state i {
    font-size: 3rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */
@media (max-width: 768px) {
    .header-content h1 {
        font-size: 1.25rem;
    }

    .nav-link {
        padding: 0.75rem 1rem;
        font-size: 0.875rem;
    }

    .nav-link i {
        display: none;
    }

    .dashboard-grid {
        grid-template-columns: 1fr;
    }

    .charts-grid {
        grid-template-columns: 1fr;
    }

    .accounts-grid {
        grid-template-columns: 1fr;
    }

    .filters {
        flex-direction: column;
    }

    .filters > * {
        width: 100%;
    }

    .transaction-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }

    .transaction-actions {
        margin-left: 0;
        width: 100%;
        justify-content: flex-end;
    }

    .modal-content {
        max-width: 100%;
        max-height: 100vh;
        border-radius: 0;
    }

    .card-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .card-header .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .summary-card {
        flex-direction: column;
        text-align: center;
    }

    .card-content .amount {
        font-size: 1.5rem;
    }
}

/* ============================================
   ANIMATIONS
   ============================================ */
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.loading {
    animation: pulse 1.5s ease-in-out infinite;
}

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
    .app-header,
    .main-nav,
    .btn,
    .modal {
        display: none !important;
    }

    body {
        background-color: white;
        color: black;
    }

    .card {
        box-shadow: none;
        border: 1px solid #ddd;
        page-break-inside: avoid;
    }
}

/* ============================================
   ACCESSIBILITY
   ============================================ */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

*:focus-visible {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* ============================================
   SCROLLBAR STYLING
   ============================================ */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background-color: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background-color: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background-color: var(--text-muted);
}

/* Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--border-color) var(--bg-secondary);
}