/* CSS tối ưu cho SEO và trải nghiệm người dùng */
    :root {
        --font-primary: 'Montserrat';
        --font-secondary: 'Montserrat';
        --clr-primary: #ff0000;
        --clr-secondary: #0a66c2;
        --clr-text: #333;
        --clr-bg-light: #fafafa;
        --clr-bg-card: #fff;
        --clr-border: #eee;
        --clr-accent-light: #f8f9fa;
        --radius-sm: 4px;
        --radius-md: 8px;
        --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
        --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
        --transition-fast: 0.2s ease-in-out;
        --font-family: 'Montserrat';
    }
    
  
    *, *::before, *::after {
        box-sizing: border-box;
        margin: 0;
        padding: 0;
    }
    
    html {
        scroll-behavior: smooth;
    }
    
    body {
        font-family: 'Montserrat';
        line-height: 1.65;
        color: var(--clr-text);
        background: var(--clr-bg-light);
        font-size: 18px;
        -webkit-font-smoothing: antialiased;
    }


    html {
        -webkit-text-size-adjust: 100%;
        text-size-adjust: 100%;
        
    }

    /* Đồng bộ font cho các khối chính nhưng vẫn giữ ngoại lệ cho Icon */
    header *:not(i), footer *:not(i), .main-layout *:not(i) {
        font-family: 'Montserrat'!important;
    }
    
    /* Utility class cho screen readers */
    .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;
    }
    
    a {
        text-decoration: none;
        color: var(--clr-primary);
        transition: var(--transition-fast);
    }
    
    a:hover {
        text-decoration: underline;
    }
    
    img {
        max-width: 100%;
        display: block;
        height: auto;
    }
    
    .container-layout {
        max-width: 1350px;
        margin: 0 auto;
        padding: 0 1.5rem;
    }
    
    /* Breadcrumb styles */
    .breadcrumb {
        display: flex;
        flex-wrap: wrap;
        list-style: none;
        padding: 1rem 0;
        margin-bottom: 1.5rem;
        background: transparent;
    }
    
    .breadcrumb-item {
        display: flex;
        align-items: center;
    }
    
    .breadcrumb-item:not(:last-child)::after {
        content: "›";
        margin: 0 0.5rem;
        color: #999;
    }
    
    .breadcrumb-item a {
        color: #666;
        font-size: 14px;
    }
    
    .breadcrumb-item.active {
        color: #333;
        font-size: 14px;
    }
    
    .main-layout {
        display: flex;
        gap: 2rem;
    }
    
    .article {
        flex: 1;
        min-width: 0;
    }
    
    .sidebar {
        width: 300px;
        flex-shrink: 0;
    }
    
    .article__content {
        background: var(--clr-bg-card);
        padding: 2rem;
        border-radius: var(--radius-md);
        box-shadow: var(--shadow-md);
    }
    
    /* Typography hierarchy cho SEO */
    .article-title {
        font-size: 42px;
        font-weight: 600;
        line-height: 1.25;
        margin-bottom: 0.8rem;
        color: #111;
        letter-spacing: -0.02em;
    }
    
    /* H2 - Subheadings chính */
    .article__context h2, 
    .article__summary h2,
    .related-articles h2 {
        font-size: clamp(1.4rem, 2.8vw, 1.9rem);
        font-weight: 500;
        line-height: 1.3;
        color: #003366; /* Màu xanh đậm chuyên nghiệp */
        margin-top: 1.2rem;
        margin-bottom: 0.5rem;
    }
    
    .article__context > *:first-child,
    .article__summary > *:first-child {
        margin-top: 0 !important;
    }
    
    /* H3 - Sub-subheadings */
    .article__context h3,
    .article__summary h3,
    .rosa-contact h3 {
        font-size: clamp(1.2rem, 2vw, 1.5rem);
        font-weight: 500;
        line-height: 1.2;
        color: #333;
        margin-top: 0.6rem;
        margin-bottom: 0.3rem;
    }
    
    /* H4, H5, H6 */
    .article__context h4 { font-size: 1.25rem; }
    .article__context h5 { font-size: 1.125rem; }
    .article__context h6 { font-size: 1rem; }
    
    .article__context h4,
    .article__context h5,
    .article__context h6 {
        font-weight: 600;
        margin-top: 0.75rem;
        margin-bottom: 0.4rem;
    }
    
    /* Paragraphs - Gọn gàng nhất có thể */
    .article__context p,
    .article__summary p {
        font-size: 1.05rem;
        line-height: 1.6;
        margin-bottom: 0.5rem;
        text-align: justify;
    }
    
    /* Ép font cho tất cả các phần tử con có thể có inline style từ DB */
    .article__context *, .article__summary * {
        font-family: 'Montserrat' !important;
        line-height: inherit;
    }
    
    .article__context p:last-child,
    .article__summary p:last-child {
        margin-bottom: 0;
    }
    
    .article-image {
        max-width: 100%;
        height: auto;
        margin: 0.5rem auto;
        display: block;
        border-radius: var(--radius-md);
        box-shadow: var(--shadow-sm);
    }
    
    /* Article meta information */
    .article-info {
        border-bottom: 1px solid var(--clr-border);
        padding-bottom: 1rem;
        margin-bottom: 1.5rem;
    }
    
    .article-meta {
        display: flex;
        justify-content: space-between;
        align-items: center;
        flex-wrap: wrap;
        gap: 1rem;
    }
    
    .article-meta-left {
        font-size: 0.9375rem;
        color: #666;
    }
    
    .article-author {
        font-weight: 500;
    }
    
    /* Lists */
    .article__context ul,
    .article__context ol,
    .article__summary ul,
    .article__summary ol {
        margin-left: 2rem;
        margin-bottom: 1.5rem;
    }
    
    .article__context li,
    .article__summary li {
        margin-bottom: 0.5rem;
        line-height: 1.7;
    }
    
    /* Tables */
    .article-table {
        width: 100%;
        border-collapse: collapse;
        margin: 2rem 0;
        overflow-x: auto;
        display: block;
    }
    
    .article-table th,
    .article-table td {
        padding: 0.75rem;
        text-align: left;
        border: 1px solid var(--clr-border);
    }
    
    .article-table th {
        background: var(--clr-accent-light);
        font-weight: 600;
    }
    
    .article__context p + img,
    .article__context img + p {
        margin-top: 0.6rem;
    }
    
    /* Social icons */
    .social-icons {
        display: flex;
        align-items: center;
        gap: 1rem;
    }
    
    .social-icons a {
        transition: transform 0.2s;
    }
    
    .social-icons a:hover {
        transform: translateY(-2px);
    }

    .share-mark {
        display: inline-flex;
        min-width: 26px;
        min-height: 26px;
        align-items: center;
        justify-content: center;
        font-family: Arial, sans-serif;
        font-size: 19px;
        font-weight: 700;
        line-height: 1;
    }

    .share-facebook {
        color: #1877F2;
    }

    .share-linkedin {
        color: #0A66C2;
        font-size: 16px;
    }

    .share-copy {
        color: #333;
    }
    
    /* Tags section */
    .article__tag {
        margin-top: 2rem;
        padding-top: 1.5rem;
        border-top: 1px solid var(--clr-border);
    }
    
    .tag-title {
        font-size: 1.125rem;
        font-weight: 600;
        margin-bottom: 1rem;
        color: #555;
    }
    
    .tag-list {
        display: flex;
        flex-wrap: wrap;
        gap: 0.75rem;
    }
    
    .article_link {
        background: var(--clr-accent-light);
        color: var(--clr-primary);
        padding: 0.5rem 1rem;
        border-radius: 9999px;
        font-size: 0.875rem;
        font-weight: 500;
        transition: all 0.2s;
    }
    
    .article_link:hover {
        background: var(--clr-primary);
        color: #fff;
        transform: translateY(-2px);
        text-decoration: none;
    }
    
    /* Contact section - ROSA Style */
    .rosa-contact {
        margin-top: 2.5rem;
        padding: 1.5rem 2rem;
        background: #fff;
        border-radius: var(--radius-md);
        border: 1px solid #ff000033;
        border-left: 5px solid #ff0000;
        box-shadow: 0 5px 15px rgba(255,0,0,0.05);
    }
    
    .rosa-contact p:first-child {
        color: #ff0000;
        font-weight: 500;
        font-size: 1.2rem;
        text-transform: uppercase;
        margin-bottom: 1rem;
        letter-spacing: 0.05em;
    }
    
    .rosa-contact address {
        font-style: normal;
        font-size: 15px;
    }
    
    .rosa-contact address p {
        margin-bottom: 0.5rem;
    }
    
    .rosa-contact a {
        color: #ff0000;
        font-weight: 600;
    }
    
    /* Related articles - Premium List */
    .related-articles {
        margin-top: 2.5rem;
        padding: 1.5rem 2rem;
        background: #fff;
        border-radius: var(--radius-md);
        border: 1px solid var(--clr-border);
    }
    
    .related-articles p:first-child {
        font-weight: 700;
        font-size: 1.1rem;
        margin-bottom: 1rem;
        color: #333;
        display: flex;
        align-items: center;
        gap: 0.5rem;
    }
    
    .related-articles p:first-child::before {
        content: '';
        width: 4px;
        height: 18px;
        background: var(--clr-primary);
        display: inline-block;
    }
    
    .related-list {
        list-style: none;
        padding: 0;
    }
    
    .related-list li {
        padding: 0.6rem 0;
        border-bottom: 1px dashed #eee;
        display: flex;
        align-items: center;
        gap: 10px;
    }
    
    .related-list li::before {
        content: '›';
        color: #ff0000;
        font-family: Arial, sans-serif;
        font-size: 18px;
    }
    
    .related-list li a {
        color: #444;
        font-size: 15px;
        font-weight: 500;
    }
    
    .related-list li a:hover {
        color: #ff0000;
        text-decoration: none;
        transform: translateX(5px);
    }
    
    .related-list li:last-child {
        border-bottom: none;
    }
    
    .related-list time {
        font-size: 0.875rem;
        color: #999;
        margin-left: 0.5rem;
    }
    
    /* Copy notification */
    .copy-notification {
        position: fixed;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        background: rgba(0, 0, 0, 0.8);
        color: white;
        padding: 1rem 2rem;
        border-radius: var(--radius-md);
        z-index: 1000;
        animation: fadeIn 0.3s;
    }
    
    @keyframes fadeIn {
        from { opacity: 0; }
        to { opacity: 1; }
    }
    
    /* Responsive Design */
    @media (max-width: 1024px) {
        .sidebar {
            display: none;
        }
    }
    
    @media (max-width: 768px) {
        .article__content {
            padding: 1.5rem;
        }
        
        .article-title {
            font-size: 1.75rem;
        }
        
        .article__context h2,
        .article__summary h2 {
            font-size: 1.5rem;
        }
        
        .article__context h3,
        .article__summary h3 {
            font-size: 1.25rem;
        }
        
        .article-meta {
            flex-direction: column;
            align-items: flex-start;
        }
        
        .rosa-contact {
            padding: 1.5rem;
        }
    }
    
    @media (max-width: 480px) {
        .container-layout {
            padding: 0 1rem;
        }
        
        .article__content {
            padding: 1rem;
        }
        
        .article-title {
            font-size: 1.5rem;
        }
        
        .breadcrumb {
            font-size: 12px;
        }
    }
    
    /* Print styles */
    @media print {
        .social-icons,
        .sidebar,
        .related-articles,
        .breadcrumb {
            display: none;
        }
        
        .article__content {
            box-shadow: none;
            padding: 0;
        }
        
        body {
            background: white;
        }
    }