/* ============================================================
   FNB Budget Tracker - Main Stylesheet (Mobile-Ready)
   ============================================================ */

/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --success-color: #16a34a;
    --danger-color: #dc2626;
    --warning-color: #ea580c;
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --text-primary: #0f172a;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --sidebar-bg: #1e293b;
    --sidebar-text: #e2e8f0;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
}

/* Container Layout */
.container {
    display: flex;
    min-height: 100vh;
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 1001;
    background: var(--primary-color);
    color: #fff;
    border: none;
    padding: 0.75rem;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 1.5rem;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.mobile-menu-toggle:active {
    transform: scale(0.95);
}

/* Sidebar Overlay (mobile) */
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
}

.sidebar-overlay.active {
    display: block;
}

/* Sidebar Navigation */
.sidebar {
    width: 260px;
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    padding: 1.5rem;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    z-index: 1000;
    transition: transform 0.3s ease;
}

.logo {
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.logo h2 {
    font-size: 1.5rem;
    color: #fff;
}

.nav-menu {
    list-style: none;
}

.nav-menu li {
    margin-bottom: 0.5rem;
}

.nav-menu a {
    display: flex;
    align-items: center;
    padding: 0.75rem 1rem;
    color: var(--sidebar-text);
    text-decoration: none;
    border-radius: 0.5rem;
    transition: all 0.2s;
    min-height: 44px; /* Touch-friendly */
}

.nav-menu a:hover {
    background: rgba(255, 255, 255, 0.1);
    color: #fff;
}

.nav-menu a.active {
    background: var(--primary-color);
    color: #fff;
}

.badge {
    margin-left: auto;
    padding: 0.25rem 0.5rem;
    background: var(--warning-color);
    color: #fff;
    font-size: 0.75rem;
    border-radius: 0.25rem;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 260px;
    padding: 2rem;
    max-width: 1400px;
    width: 100%;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.page-header h1 {
    font-size: 2rem;
    font-weight: 700;
}

/* 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-secondary);
    padding: 1.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.stat-icon {
    font-size: 2.5rem;
    opacity: 0.8;
}

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

.stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--success-color);
}

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

/* Charts Grid */
.charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.chart-card {
    background: var(--bg-secondary);
    padding: 1.5rem;
    border-radius: 0.75rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.chart-card h3 {
    margin-bottom: 1rem;
    font-size: 1.125rem;
}

.chart-card canvas {
    max-height: 300px;
}

/* Card Component */
.card {
    background: var(--bg-secondary);
    border-radius: 0.75rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    margin-bottom: 2rem;
}

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

.card-header h3 {
    font-size: 1.25rem;
    font-weight: 600;
}

/* Table */
.table-container {
    overflow-x: auto;
    -webkit-overflow-scrolling: touch; /* Smooth scrolling on iOS */
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    min-width: 600px; /* Prevent table from being too narrow */
}

.data-table thead {
    background: var(--bg-primary);
}

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

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

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

.data-table .loading {
    text-align: center;
    padding: 2rem;
    color: var(--text-secondary);
}

/* Buttons */
.btn {
    padding: 0.625rem 1.25rem;
    border: none;
    border-radius: 0.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    text-decoration: none;
    display: inline-block;
    min-height: 44px; /* Touch-friendly */
    line-height: 1.5;
}

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

.btn-primary:hover {
    background: #1d4ed8;
}

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

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

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

.btn-success:hover {
    background: #15803d;
}

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

.btn-danger:hover {
    background: #b91c1c;
}

.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.75rem;
    min-height: 36px;
}

/* Alerts */
.alert {
    padding: 1rem 1.5rem;
    border-radius: 0.5rem;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
}

.alert-warning {
    background: #fef3c7;
    border-left: 4px solid var(--warning-color);
    color: #92400e;
}

.alert-success {
    background: #d1fae5;
    border-left: 4px solid var(--success-color);
    color: #065f46;
}

.alert-danger {
    background: #fee2e2;
    border-left: 4px solid var(--danger-color);
    color: #991b1b;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

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

.form-control {
    width: 100%;
    padding: 0.625rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    font-size: 0.875rem;
    transition: border-color 0.2s;
    min-height: 44px; /* Touch-friendly */
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2364748b'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.75rem center;
    background-size: 1.25rem;
    padding-right: 2.5rem;
}

.file-upload {
    border: 2px dashed var(--border-color);
    border-radius: 0.75rem;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
}

.file-upload:hover {
    border-color: var(--primary-color);
    background: var(--bg-primary);
}

.file-upload input[type="file"] {
    display: none;
}

/* Category Badge */
.category-badge {
    padding: 0.25rem 0.75rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 500;
    background: var(--bg-primary);
    color: var(--text-secondary);
}

/* Amount Display */
.amount-positive {
    color: var(--success-color);
    font-weight: 600;
}

.amount-negative {
    color: var(--danger-color);
    font-weight: 600;
}

/* Loading Spinner */
.spinner {
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    width: 2rem;
    height: 2rem;
    animation: spin 0.8s linear infinite;
    margin: 0 auto;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================================
   RESPONSIVE DESIGN - MOBILE OPTIMIZATIONS
   ============================================================ */

/* Tablet */
@media (max-width: 1024px) {
    .mobile-menu-toggle {
        display: block;
    }
    
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.mobile-open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
        padding-top: 4rem; /* Space for hamburger menu */
    }
    
    .charts-grid {
        grid-template-columns: 1fr;
    }
}

/* Mobile */
@media (max-width: 768px) {
    .main-content {
        padding: 1rem;
        padding-top: 4rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .stat-card {
        padding: 1rem;
    }
    
    .stat-icon {
        font-size: 2rem;
    }
    
    .stat-value {
        font-size: 1.5rem;
    }
    
    .page-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .page-header h1 {
        font-size: 1.5rem;
    }
    
    .card-header {
        padding: 1rem;
    }
    
    .data-table th,
    .data-table td {
        padding: 0.75rem 0.5rem;
        font-size: 0.875rem;
    }
    
    .charts-grid {
        gap: 1rem;
    }
    
    .chart-card {
        padding: 1rem;
    }
    
    /* Make buttons full-width on mobile */
    .btn-block-mobile {
        width: 100%;
        display: block;
    }
}

/* Small Mobile */
@media (max-width: 480px) {
    .main-content {
        padding: 0.75rem;
        padding-top: 4rem;
    }
    
    .stat-value {
        font-size: 1.25rem;
    }
    
    .page-header h1 {
        font-size: 1.25rem;
    }
    
    .sidebar {
        width: 80%;
        max-width: 260px;
    }
    
    .data-table {
        font-size: 0.8125rem;
        min-width: 500px;
    }
}

/* Utility Classes */
.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.hidden { display: none; }