:root {
            --primary: #0056b3;
            --primary-dark: #003d82;
            --secondary: #6c757d;
            --success: #28a745;
            --warning: #ffc107;
            --danger: #dc3545;
            --light: #f8f9fa;
            --dark: #343a40;
            --border: #dee2e6;
            --shadow: rgba(0,0,0,0.1);
            --transition: all 0.3s ease;
        }

        * { box-sizing: border-box; }
        
        body { 
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
            margin: 0; 
            padding: 0;
            min-height: 100vh;
            line-height: 1.6;
        }

        /* Banner Styles */
        .banner-container {
            position: relative;
            z-index: 100;
        }

        .top-banners {
            display: flex;
            justify-content: space-between;
            align-items: center;
            max-width: 1400px;
            margin: 0 auto;
            padding: 10px 20px;
            gap: 20px;
        }

        .leaderboard-banner {
            flex: 1;
            max-width: 728px;
            height: 90px;
            background: #fff;
            border: 2px solid var(--border);
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            overflow: hidden;
            box-shadow: 0 4px 12px var(--shadow);
        }

        .text-banner {
            width: 300px;
            height: 90px;
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            color: white;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            font-weight: 600;
            font-size: 1.1rem;
            box-shadow: 0 4px 12px var(--shadow);
            padding: 10px;
        }

        

        .mobile-banners {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 10px;
            padding: 20px;
            margin-top: 40px;
        }

        .mobile-banner {
            width: 300px;
            height: 50px;
            background: #fff;
            border: 2px solid var(--border);
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            overflow: hidden;
            box-shadow: 0 4px 12px var(--shadow);
        }

        .banner-image {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .banner-placeholder {
            color: var(--secondary);
            font-size: 0.9rem;
            text-align: center;
            padding: 10px;
        }

        .banner-purchase-btn {
            background: var(--warning);
            color: white;
            border: none;
            padding: 5px 10px;
            border-radius: 4px;
            font-size: 0.8rem;
            cursor: pointer;
            transition: var(--transition);
        }

        .banner-purchase-btn:hover {
            background: #e0a800;
            transform: translateY(-1px);
        }

        /* Navigation Tabs */
        .navigation-tabs {
            background: white;
            box-shadow: 0 4px 12px var(--shadow);
            border-radius: 12px;
            margin: 20px auto;
            max-width: 1400px;
            overflow: hidden;
        }

        .nav-tabs-container {
            display: flex;
            justify-content: center;
            align-items: center;
            flex-wrap: wrap;
            padding: 8px;
            gap: 4px;
        }

        .nav-tab {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 12px 20px;
            text-decoration: none;
            color: var(--secondary);
            font-weight: 600;
            font-size: 1rem;
            border-radius: 8px;
            transition: var(--transition);
            position: relative;
            background: transparent;
            min-height: 48px;
            justify-content: center;
        }

        .nav-tab:hover {
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            color: white;
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(0, 86, 179, 0.3);
        }

        .nav-tab:active {
            transform: translateY(0);
        }

        .nav-icon {
            font-size: 1.2rem;
            display: flex;
            align-items: center;
        }

        .nav-text {
            white-space: nowrap;
        }

        /* Navigation tab animations */
        .nav-tab::before {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            width: 0;
            height: 3px;
            background: var(--primary);
            transition: all 0.3s ease;
            transform: translateX(-50%);
        }

        .nav-tab:hover::before {
            width: 80%;
        }

        /* Main content adjustments for skyscraper banners */
        .main-content {
            max-width: 1400px;
            margin: 0 auto;
            padding: 20px;
        }

        /* Hide skyscrapers on mobile */
        @media (max-width: 1200px) {
            .skyscraper-banners {
                display: none;
            }
        }

        @media (max-width: 768px) {
            .top-banners {
                flex-direction: column;
                padding: 10px;
                gap: 10px;
            }

            .leaderboard-banner {
                width: 100%;
                max-width: 100%;
                height: 70px;
            }

            .text-banner {
                width: 100%;
                height: 70px;
                font-size: 1rem;
            }

            .mobile-banners {
                flex-direction: column;
                align-items: center;
            }

            .mobile-banner {
                width: 100%;
                max-width: 300px;
            }
        }

        /* Banner Purchase Modal */
        .modal {
            display: none;
            position: fixed;
            z-index: 1000;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            background: rgba(0,0,0,0.5);
            backdrop-filter: blur(5px);
        }

        .modal-content {
            background: white;
            margin: 5% auto;
            padding: 0;
            border-radius: 16px;
            width: 90%;
            max-width: 600px;
            max-height: 90vh;
            overflow-y: auto;
            box-shadow: 0 20px 60px rgba(0,0,0,0.3);
        }

        .modal-header {
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            color: white;
            padding: 20px;
            border-radius: 16px 16px 0 0;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .modal-body {
            padding: 30px;
        }

        .close {
            background: none;
            border: none;
            color: white;
            font-size: 24px;
            cursor: pointer;
            padding: 0;
            width: 30px;
            height: 30px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
            transition: var(--transition);
        }

        .close:hover {
            background: rgba(255,255,255,0.2);
        }

        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            margin-bottom: 8px;
            font-weight: 600;
            color: var(--dark);
        }

        .form-input, .form-select, .form-textarea {
            width: 100%;
            padding: 12px 16px;
            border: 2px solid var(--border);
            border-radius: 8px;
            font-size: 1rem;
            transition: var(--transition);
            font-family: inherit;
        }

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

        .form-input:focus, .form-select:focus, .form-textarea:focus {
            outline: none;
            border-color: var(--primary);
            box-shadow: 0 0 0 3px rgba(0, 86, 179, 0.1);
        }

        .price-display {
            background: linear-gradient(135deg, #e8f5e8 0%, #d4edda 100%);
            border: 2px solid var(--success);
            border-radius: 8px;
            padding: 16px;
            margin: 20px 0;
            text-align: center;
        }

        .price-amount {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--success);
        }

        .purchase-btn {
            background: linear-gradient(135deg, var(--success) 0%, #218838 100%);
            color: white;
            border: none;
            border-radius: 8px;
            padding: 16px 32px;
            font-weight: 600;
            cursor: pointer;
            font-size: 1.1rem;
            width: 100%;
            transition: var(--transition);
        }

        .purchase-btn:hover:not(:disabled) {
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(40, 167, 69, 0.3);
        }

        .purchase-btn:disabled {
            background: var(--secondary);
            cursor: not-allowed;
        }

        /* Rest of existing styles... */
        h1 { 
            text-align: center; 
            font-size: clamp(1.5rem, 4vw, 2.5rem);
            margin: 0 0 2rem 0;
            color: var(--dark);
            font-weight: 700;
            text-shadow: 0 2px 4px var(--shadow);
        }

        .loading {
            display: inline-flex;
            align-items: center;
            gap: 8px;
        }

        .spinner {
            width: 16px;
            height: 16px;
            border: 2px solid #f3f3f3;
            border-top: 2px solid var(--primary);
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }

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

        .donation-form-block {
            background: linear-gradient(135deg, #fff6ec 0%, #ffe8cc 100%);
            border: 2px solid var(--warning);
            border-radius: 16px;
            max-width: 500px;
            margin: 0 auto 2rem auto;
            padding: 2rem;
            box-shadow: 0 8px 32px var(--shadow);
            position: relative;
            overflow: hidden;
        }

        .donation-form-block::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 4px;
            background: linear-gradient(90deg, var(--warning), #ff9100, var(--warning));
            animation: shimmer 2s ease-in-out infinite;
        }

        @keyframes shimmer {
            0%, 100% { opacity: 1; }
            50% { opacity: 0.7; }
        }

        .donation-form-block h2 {
            margin: 0 0 1rem 0;
            color: #d68910;
            font-size: 1.5rem;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .donate-btn {
            background: linear-gradient(135deg, #ff9100 0%, #f57c00 100%);
            color: white;
            border: none;
            border-radius: 8px;
            padding: 14px 28px;
            font-weight: 600;
            cursor: pointer;
            font-size: 1.1rem;
            width: 100%;
            transition: var(--transition);
            position: relative;
            overflow: hidden;
        }

        .donate-btn:hover:not(:disabled) {
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(255, 145, 0, 0.3);
        }

        .donate-btn:disabled {
            background: var(--secondary);
            cursor: not-allowed;
            transform: none;
            box-shadow: none;
        }

        .donation-result {
            margin-top: 1rem;
            padding: 12px;
            border-radius: 8px;
            font-weight: 500;
            text-align: center;
            opacity: 0;
            transform: translateY(10px);
            transition: var(--transition);
        }

        .donation-result.show {
            opacity: 1;
            transform: translateY(0);
        }

        .success { 
            background: #d4edda; 
            color: #155724; 
            border: 1px solid #c3e6cb; 
        }

        .error { 
            background: #f8d7da; 
            color: #721c24; 
            border: 1px solid #f5c6cb; 
        }

        .info { 
            background: #d1ecf1; 
            color: #0c5460; 
            border: 1px solid #bee5eb; 
        }

        .tabs {
            display: flex;
            justify-content: center;
            margin: 2rem 0;
            gap: 4px;
            flex-wrap: wrap;
            background: white;
            padding: 8px;
            border-radius: 12px;
            box-shadow: 0 4px 16px var(--shadow);
        }

        .tab-btn {
            padding: 12px 24px;
            font-weight: 600;
            font-size: 1rem;
            border-radius: 8px;
            border: none;
            background: transparent;
            cursor: pointer;
            transition: var(--transition);
            color: var(--secondary);
            position: relative;
        }

        .tab-btn:hover {
            background: rgba(0, 86, 179, 0.1);
            color: var(--primary);
        }

        .tab-btn.active {
            background: var(--primary);
            color: white;
            box-shadow: 0 4px 12px rgba(0, 86, 179, 0.3);
        }

        .tab-content {
            display: none;
            background: white;
            border-radius: 12px;
            box-shadow: 0 8px 32px var(--shadow);
            overflow: hidden;
        }

        .tab-content.active {
            display: block;
        }

        .tab-header {
            padding: 2rem;
            background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
            color: white;
        }

        .tab-header h2 {
            margin: 0;
            font-size: 1.5rem;
        }

        .table-container {
            padding: 2rem;
        }

        .table-info {
            margin-bottom: 1rem;
            color: var(--secondary);
            font-size: 0.9rem;
        }

        .table-wrapper {
            overflow-x: auto;
            border-radius: 8px;
            border: 1px solid var(--border);
        }

        .data-table {
            width: 100%;
            border-collapse: collapse;
            background: white;
            font-size: 0.9rem;
        }

        .data-table th {
            background: var(--dark);
            color: white;
            padding: 16px 12px;
            text-align: left;
            font-weight: 600;
            position: sticky;
            top: 0;
            z-index: 10;
            white-space: nowrap;
        }

        .data-table td {
            padding: 12px;
            border-bottom: 1px solid var(--border);
            word-wrap: break-word;
        }

        .data-table tr:hover {
            background: rgba(0, 86, 179, 0.05);
        }

        .no-results {
            text-align: center;
            padding: 3rem;
            color: var(--secondary);
            font-size: 1.1rem;
        }

        .pagination {
            display: flex;
            justify-content: center;
            gap: 8px;
            margin-top: 2rem;
            flex-wrap: wrap;
        }

        .page-btn {
            padding: 10px 16px;
            border: 1px solid var(--border);
            background: white;
            color: var(--primary);
            border-radius: 6px;
            cursor: pointer;
            transition: var(--transition);
            font-weight: 500;
        }

        .page-btn:hover {
            background: var(--primary);
            color: white;
            transform: translateY(-1px);
        }

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

        .filters {
            display: flex;
            gap: 1rem;
            margin-bottom: 2rem;
            flex-wrap: wrap;
            align-items: center;
        }

        .search-input {
            flex: 1;
            min-width: 200px;
            padding: 10px 16px;
            border: 2px solid var(--border);
            border-radius: 8px;
            font-size: 1rem;
        }

        .filter-select {
            padding: 10px 16px;
            border: 2px solid var(--border);
            border-radius: 8px;
            background: white;
            min-width: 150px;
        }

        .refresh-btn {
            padding: 10px 20px;
            background: var(--success);
            color: white;
            border: none;
            border-radius: 8px;
            cursor: pointer;
            font-weight: 500;
            transition: var(--transition);
        }

        .refresh-btn:hover {
            background: #218838;
            transform: translateY(-1px);
        }

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

        .tab-btn:focus,
        .page-btn:focus,
        .donate-btn:focus,
        .refresh-btn:focus {
            outline: 2px solid var(--primary);
            outline-offset: 2px;
        }

        @media (prefers-reduced-motion: no-preference) {
            .tab-content.active {
                animation: fadeIn 0.3s ease-in-out;
            }

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

        /* Advertise Button */
        .advertise-btn {
            position: fixed;
            bottom: 20px;
            right: 20px;
            background: linear-gradient(135deg, var(--warning) 0%, #e0a800 100%);
            color: white;
            border: none;
            border-radius: 50px;
            padding: 15px 25px;
            font-weight: 600;
            cursor: pointer;
            font-size: 1rem;
            box-shadow: 0 8px 25px rgba(255, 193, 7, 0.4);
            transition: var(--transition);
            z-index: 1000;
        }

        .advertise-btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 12px 35px rgba(255, 193, 7, 0.6);
        }

        @media (max-width: 768px) {
            .advertise-btn {
                bottom: 10px;
                right: 10px;
                padding: 12px 20px;
                font-size: 0.9rem;
            }
        }

/* =================================================================
   FILE UPLOAD
   ================================================================= */

.file-upload-area {
    border: 3px dashed #ddd;
    border-radius: 8px;
    padding: 30px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    position: relative;
    min-height: 120px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.file-upload-area:hover {
    border-color: #007bff;
    background-color: #f8f9fa;
}

.file-upload-area.dragover {
    border-color: #28a745 !important;
    background: #f0fff4 !important;
    transform: scale(1.02);
}

.upload-icon {
    font-size: 2.5rem;
    color: #6c757d;
    margin-bottom: 12px;
}

.upload-text {
    font-size: 1rem;
    font-weight: 500;
    color: #495057;
    margin-bottom: 4px;
}

.upload-subtext {
    font-size: 0.85rem;
    color: #6c757d;
}

.image-preview {
    max-width: 200px !important;
    max-height: 150px !important;
    border-radius: 6px;
    margin-top: 15px;
    display: none;
    border: 2px solid #dee2e6;
    box-shadow: 0 3px 6px rgba(0,0,0,0.1);
}

.image-preview.show {
    display: block;
}