:root {
            --bg-primary: #0a0a0a;
            --bg-secondary: #1a1a1a;
            --bg-tertiary: #2a2a2a;
            --bg-card: #1e1e1e;
            --text-primary: #ffffff;
            --text-secondary: #e0e0e0;
            --text-muted: #a0a0a0;
            --accent-primary: #00d4ff;
            --accent-secondary: #0099cc;
            --accent-gradient: linear-gradient(135deg, #00d4ff, #0099cc);
            --border-color: #333;
            --border-light: #444;
            --shadow-light: rgba(0, 0, 0, 0.2);
            --shadow-medium: rgba(0, 0, 0, 0.4);
            --shadow-heavy: rgba(0, 0, 0, 0.6);
            --success-color: #00ff88;
            --warning-color: #ffaa00;
            --error-color: #ff4444;
        }

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

        body {
            font-family: 'Poppins', sans-serif;
            background: var(--bg-primary);
            color: var(--text-primary);
            line-height: 1.6;
            overflow-x: hidden;
        }

        /* Loading Animation */
        .loading-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: var(--bg-primary);
            display: flex;
            justify-content: center;
            align-items: center;
            z-index: 9999;
            transition: opacity 0.5s ease;
        }

        .loading-spinner {
            width: 50px;
            height: 50px;
            border: 3px solid var(--border-color);
            border-top: 3px solid var(--accent-primary);
            border-radius: 50%;
            animation: spin 1s linear infinite;
        }

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

        /* Page Header */
        .page-header {
            background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 50%, var(--bg-tertiary) 100%);
            padding: 3rem 0 1.5rem;
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .page-header::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: radial-gradient(circle at 50% 50%, rgba(0, 212, 255, 0.1) 0%, transparent 70%);
            animation: pulse 4s ease-in-out infinite;
        }

        @keyframes pulse {
            0%, 100% { opacity: 0.5; }
            50% { opacity: 1; }
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 1.5rem;
            position: relative;
            z-index: 1;
        }

        .page-title {
            font-size: 2.8rem;
            font-weight: 800;
            margin-bottom: 0.8rem;
            background: var(--accent-gradient);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            animation: slideInDown 1s ease-out;
        }

        .page-subtitle {
            font-size: 1.1rem;
            color: var(--text-secondary);
            font-weight: 400;
            animation: slideInUp 1s ease-out 0.2s both;
        }

        @keyframes slideInDown {
            from {
                opacity: 0;
                transform: translateY(-30px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        @keyframes slideInUp {
            from {
                opacity: 0;
                transform: translateY(30px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        /* Search and Filter Section */
        .filter-section {
            padding: 1.5rem 0;
            background: var(--bg-secondary);
            border-bottom: 1px solid var(--border-color);
            position: sticky;
            top: 0;
            z-index: 100;
            backdrop-filter: blur(10px);
        }

        .search-container {
            max-width: 500px;
            margin: 0 auto 1.5rem;
            position: relative;
        }

        .search-input {
            width: 100%;
            padding: 0.8rem 0.8rem 0.8rem 2.5rem;
            background: var(--bg-card);
            border: 2px solid var(--border-color);
            border-radius: 25px;
            color: var(--text-primary);
            font-size: 0.9rem;
            transition: all 0.3s ease;
        }

        .search-input:focus {
            outline: none;
            border-color: var(--accent-primary);
            box-shadow: 0 0 15px rgba(0, 212, 255, 0.3);
        }

        .search-icon {
            position: absolute;
            left: 0.8rem;
            top: 50%;
            transform: translateY(-50%);
            color: var(--text-muted);
            font-size: 1rem;
        }

        .filter-buttons {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 0.8rem;
        }

        .filter-btn {
            padding: 0.6rem 1.2rem;
            font-size: 0.85rem;
            font-weight: 600;
            background: var(--bg-card);
            color: var(--text-primary);
            border: 2px solid var(--border-color);
            border-radius: 25px;
            cursor: pointer;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
        }

        .filter-btn::before {
            content: '';
            position: absolute;
            top: 0;
            left: -100%;
            width: 100%;
            height: 100%;
            background: var(--accent-gradient);
            transition: left 0.3s ease;
            z-index: -1;
        }

        .filter-btn:hover::before,
        .filter-btn.active::before {
            left: 0;
        }

        .filter-btn:hover,
        .filter-btn.active {
            color: #000;
            border-color: var(--accent-primary);
            transform: translateY(-2px);
            box-shadow: 0 5px 15px rgba(0, 212, 255, 0.3);
        }

        /* Statistics Section */
        .stats-section {
            padding: 2rem 0;
            background: var(--bg-secondary);
            margin: 1.5rem 0;
            border-radius: 15px;
            border: 1px solid var(--border-color);
        }

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

        .stat-item {
            text-align: center;
            padding: 1.5rem;
            border-radius: 12px;
            background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-tertiary) 100%);
            border: 1px solid var(--border-light);
            transition: all 0.4s ease;
            position: relative;
            overflow: hidden;
        }

        .stat-item::before {
            content: '';
            position: absolute;
            top: -50%;
            left: -50%;
            width: 200%;
            height: 200%;
            background: radial-gradient(circle, rgba(0, 212, 255, 0.1) 0%, transparent 70%);
            animation: rotate 10s linear infinite;
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .stat-item:hover::before {
            opacity: 1;
        }

        @keyframes rotate {
            from { transform: rotate(0deg); }
            to { transform: rotate(360deg); }
        }

        .stat-item:hover {
            transform: translateY(-5px) scale(1.02);
            box-shadow: 0 15px 30px rgba(0, 212, 255, 0.2);
        }

        .stat-number {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--accent-primary);
            margin-bottom: 0.3rem;
            position: relative;
            z-index: 1;
        }

        .stat-label {
            color: var(--text-secondary);
            font-weight: 500;
            font-size: 0.9rem;
            position: relative;
            z-index: 1;
        }

        /* Certificates Section */
        .certificates-section {
            padding: 2.5rem 0;
        }

        .certificates-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
            gap: 1.5rem;
        }

        .certificate-card {
            background: var(--bg-card);
            border-radius: 15px;
            border: 1px solid var(--border-color);
            overflow: hidden;
            transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
            box-shadow: 0 5px 20px var(--shadow-light);
            position: relative;
            opacity: 0;
            transform: translateY(30px);
            animation: fadeInUp 0.6s ease-out forwards;
        }

        .certificate-card:nth-child(even) {
            animation-delay: 0.1s;
        }

        .certificate-card:nth-child(3n) {
            animation-delay: 0.2s;
        }

        @keyframes fadeInUp {
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }

        .certificate-card:hover {
            transform: translateY(-8px) scale(1.02);
            box-shadow: 0 15px 40px var(--shadow-medium);
            border-color: var(--accent-primary);
        }

        .certificate-image-container {
            width: 100%;
            height: 180px;
            overflow: hidden;
            position: relative;
            background: linear-gradient(135deg, var(--bg-tertiary), var(--bg-secondary));
        }

        .certificate-full-image {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.4s ease;
        }

        .certificate-card:hover .certificate-full-image {
            transform: scale(1.05);
        }

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

        .certificate-logo {
            width: 45px;
            height: 45px;
            background: var(--bg-tertiary);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            border: 2px solid var(--border-light);
            transition: all 0.3s ease;
        }

        .certificate-card:hover .certificate-logo {
            border-color: var(--accent-primary);
            box-shadow: 0 0 15px rgba(0, 212, 255, 0.3);
        }

        .certificate-logo-img {
            width: 30px;
            height: 30px;
            border-radius: 6px;
            object-fit: cover;
        }

        .certificate-badge {
            background: var(--success-color);
            color: #000;
            padding: 0.3rem 0.8rem;
            border-radius: 15px;
            font-size: 0.7rem;
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }

        .certificate-content {
            padding: 1.2rem;
        }

        .certificate-content h3 {
            color: var(--text-primary);
            font-size: 1.1rem;
            font-weight: 700;
            margin-bottom: 0.5rem;
            line-height: 1.3;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .certificate-issuer {
            color: var(--accent-primary);
            font-weight: 600;
            margin-bottom: 0.3rem;
            font-size: 0.9rem;
        }

        .certificate-date {
            color: var(--text-muted);
            font-size: 0.8rem;
            margin-bottom: 1rem;
        }

        .certificate-description {
            color: var(--text-secondary);
            line-height: 1.5;
            margin-bottom: 1rem;
            font-size: 0.85rem;
            display: -webkit-box;
            -webkit-line-clamp: 3;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .certificate-skills {
            display: flex;
            flex-wrap: wrap;
            gap: 0.4rem;
            margin-bottom: 1.2rem;
        }

        .skill-tag {
            background: linear-gradient(135deg, var(--bg-tertiary), var(--bg-secondary));
            color: var(--text-secondary);
            padding: 0.25rem 0.6rem;
            border-radius: 12px;
            font-size: 0.7rem;
            border: 1px solid var(--border-light);
            transition: all 0.3s ease;
            font-weight: 500;
        }

        .skill-tag:hover {
            background: var(--accent-gradient);
            color: #000;
            transform: translateY(-1px);
        }

        .certificate-actions {
            display: flex;
            gap: 0.8rem;
        }

        .btn {
            flex: 1;
            text-align: center;
            padding: 0.6rem 1rem;
            font-size: 0.8rem;
            font-weight: 600;
            border-radius: 8px;
            text-decoration: none;
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
            border: none;
            cursor: pointer;
        }

        .btn-outline {
            background: transparent;
            color: var(--accent-primary);
            border: 2px solid var(--accent-primary);
        }

        .btn-outline:hover {
            background: var(--accent-primary);
            color: #000;
            transform: translateY(-2px);
            box-shadow: 0 5px 15px rgba(0, 212, 255, 0.3);
        }

        .btn-secondary {
            background: var(--bg-tertiary);
            color: var(--text-primary);
            border: 2px solid var(--border-light);
        }

        .btn-secondary:hover {
            background: var(--text-primary);
            color: #000;
            transform: translateY(-2px);
        }

        /* Modal Styles */
        .modal {
            display: none;
            position: fixed;
            z-index: 1000;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            background-color: rgba(0, 0, 0, 0.8);
            backdrop-filter: blur(5px);
        }

        .modal-content {
            background-color: var(--bg-card);
            margin: 3% auto;
            padding: 0;
            border: 1px solid var(--border-color);
            border-radius: 15px;
            width: 90%;
            max-width: 700px;
            max-height: 90vh;
            overflow-y: auto;
            animation: modalSlideIn 0.3s ease-out;
        }

        @keyframes modalSlideIn {
            from {
                opacity: 0;
                transform: translateY(-30px) scale(0.9);
            }
            to {
                opacity: 1;
                transform: translateY(0) scale(1);
            }
        }

        .modal-header {
            padding: 1.2rem;
            border-bottom: 1px solid var(--border-color);
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .modal-title {
            font-size: 1.3rem;
            font-weight: 700;
            color: var(--text-primary);
        }

        .close {
            color: var(--text-muted);
            font-size: 1.8rem;
            font-weight: bold;
            cursor: pointer;
            transition: color 0.3s ease;
        }

        .close:hover {
            color: var(--accent-primary);
        }

        .modal-body {
            padding: 1.5rem;
        }

        .modal-certificate-image {
            width: 100%;
            border-radius: 10px;
            margin-bottom: 1rem;
        }

        /* No Results Message */
        .no-results {
            text-align: center;
            padding: 3rem 2rem;
            color: var(--text-muted);
            font-size: 1.1rem;
            display: none;
        }

        .no-results-icon {
            font-size: 3rem;
            margin-bottom: 1rem;
            opacity: 0.5;
        }

        /* Scroll to Top Button */
        .scroll-top {
            position: fixed;
            bottom: 1.5rem;
            right: 1.5rem;
            width: 45px;
            height: 45px;
            background: var(--accent-gradient);
            color: #000;
            border: none;
            border-radius: 50%;
            cursor: pointer;
            font-size: 1.1rem;
            transition: all 0.3s ease;
            opacity: 0;
            visibility: hidden;
            z-index: 999;
        }

        .scroll-top.visible {
            opacity: 1;
            visibility: visible;
        }

        .scroll-top:hover {
            transform: translateY(-3px);
            box-shadow: 0 8px 25px rgba(0, 212, 255, 0.4);
        }

        /* Responsive Design */
        @media (max-width: 768px) {
            .page-title {
                font-size: 2.2rem;
            }

            .page-subtitle {
                font-size: 1rem;
            }

            .certificates-grid {
                grid-template-columns: 1fr;
                gap: 1.2rem;
            }

            .certificate-actions {
                flex-direction: column;
            }

            .filter-buttons {
                flex-direction: column;
                align-items: center;
            }

            .stats-grid {
                grid-template-columns: repeat(2, 1fr);
            }

            .container {
                padding: 0 1rem;
            }

            .certificate-image-container {
                height: 160px;
            }
        }

        @media (max-width: 480px) {
            .stats-grid {
                grid-template-columns: 1fr;
            }

            .stat-number {
                font-size: 2rem;
            }

            .certificate-content {
                padding: 1rem;
            }

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

        /* Print Styles */
        @media print {
            .filter-section,
            .scroll-top,
            .certificate-actions {
                display: none;
            }

            .certificate-card {
                break-inside: avoid;
                box-shadow: none;
                border: 1px solid #000;
            }
        }

        /* Hidden class for filtering */
        .hidden {
            display: none !important;
        }