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

        :root {
            --brand-blue: #005df8;
            --black: #0a0a0a;
            --white: #ffffff;
            --gray-50: #fafafa;
            --gray-100: #f5f5f5;
            --gray-200: #e5e5e5;
            --gray-300: #d4d4d4;
            --gray-600: #525252;
            --gray-900: #171717;
        }

        body {
            font-family: 'Inter', sans-serif;
            background: var(--white);
            color: var(--black);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }

        .header {
            position: fixed;
            top: 0;
            width: 100%;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(20px);
            border-bottom: 1px solid var(--gray-200);
            z-index: 1000;
        }

        .nav-container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 20px 40px;
        }

        .logo {
            font-size: 24px;
            font-weight: 800;
            color: var(--black);
            text-decoration: none;
        }

        .nav-center { display: flex; gap: 40px; }

        .nav-link {
            color: var(--black);
            text-decoration: none;
            font-size: 15px;
            font-weight: 500;
            transition: color 0.2s;
        }

        .nav-link:hover,
        .nav-link.active { color: var(--brand-blue); }

        .btn-start {
            background: var(--brand-blue);
            color: var(--white);
            padding: 12px 28px;
            text-decoration: none;
            font-weight: 600;
            font-size: 15px;
        }

        .breadcrumb-section {
            padding: 140px 40px 40px;
            background: var(--gray-50);
        }

        .breadcrumb {
            max-width: 1400px;
            margin: 0 auto;
            display: flex;
            gap: 12px;
            font-size: 14px;
        }

        .breadcrumb a {
            color: var(--gray-600);
            text-decoration: none;
        }

        /* CATEGORY HERO */
        .category-hero {
            padding: 60px 40px 80px;
            background: var(--gray-50);
        }

        .hero-content {
            max-width: 1400px;
            margin: 0 auto;
        }

        .category-title {
            font-size: clamp(32px, 5vw, 56px);
            font-weight: 900;
            line-height: 1.15;
            letter-spacing: -1.5px;
            margin-bottom: 16px;
            color: #0a0a0a !important;
        }

        .category-desc {
            font-size: 20px;
            color: var(--gray-600);
            line-height: 1.7;
            margin-bottom: 32px;
        }

        .category-stats {
            display: flex;
            gap: 40px;
            flex-wrap: wrap;
        }

        .stat-item {
            font-size: 16px;
            color: var(--gray-600);
        }

        .stat-item strong {
            color: var(--brand-blue);
            font-weight: 700;
        }

        /* FILTERS & CONTROLS */
        .controls-section {
            padding: 32px 40px;
            background: var(--white);
            border-bottom: 2px solid var(--gray-200);
        }

        .controls-container {
            max-width: 1400px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 24px;
            flex-wrap: wrap;
        }

        .filter-group {
            display: flex;
            gap: 16px;
            align-items: center;
            flex-wrap: wrap;
        }

        .filter-label {
            font-size: 14px;
            font-weight: 600;
            color: var(--gray-600);
        }

        .filter-select {
            padding: 10px 16px;
            border: 2px solid var(--gray-200);
            background: var(--white);
            font-size: 14px;
            font-weight: 500;
            cursor: pointer;
            min-width: 140px;
        }

        .filter-select:focus {
            outline: none;
            border-color: var(--brand-blue);
        }

        .results-count {
            font-size: 15px;
            color: var(--gray-600);
        }

        .view-toggle {
            display: flex;
            gap: 8px;
        }

        .view-btn {
            width: 40px;
            height: 40px;
            border: 2px solid var(--gray-200);
            background: var(--white);
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            transition: all 0.2s;
        }

        .view-btn:hover,
        .view-btn.active {
            background: var(--brand-blue);
            border-color: var(--brand-blue);
            color: var(--white);
        }

        /* SIDEBAR + CONTENT LAYOUT */
        .content-section {
            padding: 60px 40px;
        }

        .content-layout {
            max-width: 1400px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: 280px 1fr;
            gap: 60px;
        }

        /* SIDEBAR FILTERS */
        .sidebar {
            position: sticky;
            top: 120px;
            height: fit-content;
        }

        .filter-section {
            margin-bottom: 32px;
            padding-bottom: 32px;
            border-bottom: 2px solid var(--gray-200);
        }

        .filter-section:last-child {
            border-bottom: none;
        }

        .filter-title {
            font-size: 16px;
            font-weight: 700;
            margin-bottom: 16px;
        }

        .filter-options {
            list-style: none;
        }

        .filter-option {
            padding: 10px 0;
            display: flex;
            align-items: center;
            gap: 12px;
            cursor: pointer;
            transition: all 0.2s;
        }

        .filter-option:hover {
            color: var(--brand-blue);
        }

        .filter-checkbox {
            width: 20px;
            height: 20px;
            border: 2px solid var(--gray-300);
            display: flex;
            align-items: center;
            justify-content: center;
            transition: all 0.2s;
        }

        .filter-option.active .filter-checkbox {
            background: var(--brand-blue);
            border-color: var(--brand-blue);
        }

        .filter-option.active .filter-checkbox::after {
            content: '✓';
            color: var(--white);
            font-size: 12px;
            font-weight: 700;
        }

        .filter-count {
            margin-left: auto;
            font-size: 14px;
            color: var(--gray-600);
        }

        /* PRICE RANGE */
        .price-inputs {
            display: grid;
            grid-template-columns: 1fr auto 1fr;
            gap: 12px;
            align-items: center;
            margin-top: 16px;
        }

        .price-input {
            padding: 10px;
            border: 2px solid var(--gray-200);
            font-size: 14px;
        }

        /* COURSES GRID */
        .courses-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
            gap: 28px;
            width: 100%;
        }

        .course-card {
            background: var(--white);
            border: 2px solid var(--gray-200);
            overflow: hidden;
            transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
            cursor: pointer;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            height: 100%;
            width: 100%;
            box-sizing: border-box;
            border-radius: 8px;
        }

        .course-card:hover {
            border-color: var(--brand-blue);
            transform: translateY(-6px);
            box-shadow: 0 20px 45px rgba(0, 0, 0, 0.1);
        }

        .course-thumbnail {
            width: 100%;
            aspect-ratio: 16 / 9;
            min-height: 190px;
            background: var(--gray-900);
            position: relative;
            overflow: hidden;
            flex-shrink: 0;
            display: block;
        }

        .course-thumbnail img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            display: block;
            transition: transform 0.4s ease;
        }

        .course-card:hover .course-thumbnail img {
            transform: scale(1.05);
        }

        .course-badge {
            position: absolute;
            top: 12px;
            left: 12px;
            background: var(--brand-blue);
            color: var(--white);
            padding: 5px 12px;
            font-size: 11px;
            font-weight: 800;
            text-transform: uppercase;
            letter-spacing: 0.5px;
            z-index: 3;
            border-radius: 4px;
            box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
            max-width: calc(100% - 24px);
            white-space: normal;
            line-height: 1.3;
        }

        .course-level {
            position: absolute;
            bottom: 12px;
            right: 12px;
            background: rgba(10, 10, 10, 0.85);
            backdrop-filter: blur(4px);
            color: var(--white);
            padding: 5px 12px;
            font-size: 11px;
            font-weight: 700;
            z-index: 3;
            border-radius: 4px;
        }

        .course-content {
            padding: 24px;
            display: flex;
            flex-direction: column;
            flex: 1;
            justify-content: space-between;
        }

        .course-category {
            font-size: 12px;
            font-weight: 800;
            text-transform: uppercase;
            letter-spacing: 0.5px;
            color: var(--brand-blue);
            margin-bottom: 8px;
        }

        .course-title {
            font-size: 20px;
            font-weight: 800;
            margin-bottom: 10px;
            line-height: 1.35;
            color: #0a0a0a !important;
        }

        .course-title a {
            color: #0a0a0a !important;
            text-decoration: none;
            transition: color 0.2s;
        }

        .course-card:hover .course-title a {
            color: var(--brand-blue) !important;
        }

        .course-desc {
            font-size: 14px;
            color: var(--gray-600);
            line-height: 1.6;
            margin-bottom: 20px;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .course-meta {
            display: flex;
            gap: 16px;
            margin-bottom: 20px;
            flex-wrap: wrap;
            font-size: 13px;
            color: var(--gray-600);
        }

        .meta-item {
            display: flex;
            align-items: center;
            gap: 6px;
            white-space: nowrap;
        }

        .meta-item i {
            color: var(--brand-blue);
        }

        .course-footer {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding-top: 18px;
            border-top: 2px solid var(--gray-200);
            gap: 12px;
            flex-wrap: wrap;
        }

        .course-instructor {
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .instructor-avatar {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--gray-200);
            overflow: hidden;
            flex-shrink: 0;
        }

        .instructor-avatar img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .instructor-name {
            font-size: 13px;
            font-weight: 700;
            color: var(--black);
        }

        .course-price {
            text-align: right;
            margin-left: auto;
        }

        .price-amount {
            font-size: 22px;
            font-weight: 900;
            color: var(--brand-blue);
            line-height: 1;
        }

        .price-label {
            font-size: 11px;
            color: var(--gray-600);
            margin-top: 2px;
        }

        /* PAGINATION */
        .pagination {
            display: flex;
            justify-content: center;
            align-items: center;
            gap: 12px;
            margin-top: 60px;
        }

        .page-btn {
            width: 44px;
            height: 44px;
            border: 2px solid var(--gray-200);
            background: var(--white);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
        }

        .page-btn:hover,
        .page-btn.active {
            background: var(--brand-blue);
            border-color: var(--brand-blue);
            color: var(--white);
        }

        /* FOOTER */
        .footer {
            background: var(--gray-900);
            color: var(--white);
            padding: 80px 40px 40px;
        }

        .footer-content {
            max-width: 1400px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
            gap: 60px;
            margin-bottom: 60px;
        }

        .footer-logo {
            font-size: 28px;
            font-weight: 800;
            margin-bottom: 20px;
        }

        .footer-tagline {
            font-size: 15px;
            color: var(--gray-300);
            line-height: 1.7;
        }

        .footer-column h4 {
            font-size: 14px;
            font-weight: 700;
            text-transform: uppercase;
            margin-bottom: 24px;
        }

        .footer-links {
            list-style: none;
        }

        .footer-links li {
            margin-bottom: 16px;
        }

        .footer-links a {
            color: var(--gray-300);
            text-decoration: none;
            font-size: 15px;
            transition: color 0.2s;
        }

        .footer-links a:hover {
            color: var(--white);
        }

        .footer-bottom {
            max-width: 1400px;
            margin: 0 auto;
            padding-top: 40px;
            border-top: 1px solid var(--gray-600);
            text-align: center;
            color: var(--gray-300);
            font-size: 14px;
        }

        @media (max-width: 1200px) {
            .content-layout {
                grid-template-columns: 1fr;
                gap: 40px;
            }

            .sidebar {
                position: static;
                width: 100%;
            }

            .courses-grid {
                grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
                gap: 24px;
            }

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

        @media (max-width: 768px) {
            .breadcrumb-section {
                padding: 110px 20px 20px;
            }

            .category-hero {
                padding: 40px 20px 50px;
            }

            .category-title {
                font-size: 32px;
            }

            .category-desc {
                font-size: 16px;
            }

            .controls-section {
                padding: 20px;
            }

            .content-section {
                padding: 30px 20px;
            }

            .courses-grid {
                grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
                gap: 20px;
            }

            .course-content {
                padding: 18px;
            }

            .course-title {
                font-size: 18px;
            }

            .nav-center {
                display: none;
            }

            .controls-container {
                flex-direction: column;
                align-items: stretch;
            }

            .footer-content {
                grid-template-columns: 1fr;
            }
        }

        @media (max-width: 480px) {
            .breadcrumb-section {
                padding: 100px 16px 20px !important;
            }

            .category-hero,
            .controls-section,
            .content-section {
                padding-left: 16px !important;
                padding-right: 16px !important;
            }

            .courses-grid {
                grid-template-columns: 1fr !important;
            }
        }

        html {
            scroll-behavior: smooth;
        }