:root {
            --bg-color: #ffffff;
            --surface-color: #f4f4f5;
            --text-primary: #000;
            --text-secondary: #52525b;
            --accent-color: #304ffe;
            --accent-hover: #1e3bbd;
            --border-color: #e4e4e4;
        }
        [data-theme="dark"] {
            --bg-color: #000;
            --surface-color: #1a1a1a;
            --text-primary: #ffffff;
            --text-secondary: #a1a1aa;
            --accent-color: #304ffe;
            --accent-hover: #536dfe;
            --border-color: #212121;
        }
        * { box-sizing: border-box; margin: 0; padding: 0; outline: none; }
        html { scroll-behavior: smooth; }
        body {
            font-family: 'Roboto', sans-serif;
            background-color: var(--bg-color);
            color: var(--text-primary);
            line-height: 1.75;
            overflow-x: hidden;
            transition: background-color 0.4s ease, color 0.4s ease;
        }
        a { text-decoration: none; color: inherit; transition: color 0.2s; }
        img { max-width: 100%; height: auto; display: block; }
        .fade-in-up {
            opacity: 0;
            transform: translateY(25px);
            transition: opacity 0.8s ease-out, transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
        }
        .fade-in-up.visible { opacity: 1; transform: translateY(0); }
        .power-link {
            color: var(--accent-color);
            font-weight: 500;
            cursor: pointer;
            position: relative;
            padding-bottom: 2px;
        }
        .power-link:after {
            content: '';
            position: absolute; left: 0; bottom: 0;
            width: 0%; height: 2px;
            background: var(--accent-color);
            transition: width 0.3s cubic-bezier(0.25, 1, 0.5, 1);
        }
        .power-link:hover:after { width: 100%; }
        .article-card {
            transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.3s ease;
            cursor: pointer;
            display: flex;
            flex-direction: column;
            overflow: hidden;
            border-radius: 12px;
            border: 1px solid var(--border-color);
            height: 100%; 
        }
        .article-card:hover {
            border-color: var(--accent-hover);
        }
        .card-image-wrapper {
            aspect-ratio: 16/9;
            overflow: hidden;
            background: var(--surface-color);
        }
        .article-card.featured-large .card-image-wrapper {
            aspect-ratio: 16/8; 
        }
        .article-card.featured-secondary .card-image-wrapper {
            aspect-ratio: 16/9;
        }
        .card-image {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.8s cubic-bezier(0.19, 1, 0.22, 1);
        }
        .article-card:hover .card-image {
            transform: scale(1.08);
        }
        .category-tab {
            padding: 0.5rem 1.25rem;
            border-radius: 999px;
            font-size: 0.875rem;
            font-weight: 500;
            color: var(--text-secondary);
            border: 1px solid var(--border-color);
            cursor: pointer;
            transition: all 0.3s ease;
            white-space: nowrap;
            background-color: var(--bg-color);
        }
        .category-tab:hover:not(.active) {
            border-color: var(--accent-hover);
            color: var(--accent-color);
        }
        .category-tab.active {
            background-color: var(--accent-color);
            color: #fff;
            border-color: var(--accent-color);
            box-shadow: 0 3px 8px -1px rgba(48, 79, 254, 0.4);
        }
        .category-tag-cloud {
            display: flex;
            flex-wrap: wrap; 
            gap: 0.75rem; 
            justify-content: center;
        }
        #article-search {
            background-color: var(--bg-color);
            border: 3px solid var(--border-color);
            color: var(--text-primary);
            transition: border-color 0.2s ease;
            box-shadow: none;
        }
        #article-search:focus {
            border: 3px solid var(--accent-color);
        }
        #error-message, #no-results {
            border: 1px solid var(--border-color);
        }
        [data-theme="dark"] #error-message {
             border-color: #d50000; 
             background-color: #1a0808;
        }