:root {
            --primary: rgb(55,65,81);
            --primary-dark: rgb(31,41,55);
            --bg-body: #f9fafb;
            --bg-white: #ffffff;
            --text-main: #111827;
            --text-article: #374151;
            --text-muted: #6b7280;
            --border-color: #e5e7eb;
            --radius-md: 8px;
            --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
            --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
            --transition: all 0.3s ease;
        }
        * { box-sizing: border-box; margin: 0; padding: 0; }
        body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif; background-color: var(--bg-body); color: var(--text-main); line-height: 1.6; }
        a { text-decoration: none; color: inherit; transition: var(--transition); }
        ul, ol { list-style: none; }
        img { max-width: 100%; height: auto; display: block; }
        .container { width: 100%; max-width: 1000px; margin: 0 auto; padding: 0 20px; }
        
        
        .site-header { background: var(--bg-white); box-shadow: var(--shadow-sm); position: sticky; top: 0; z-index: 50; }
        .header-inner { display: flex; align-items: center; justify-content: space-between; height: 70px; max-width:1200px; margin:0 auto; padding:0 20px;}
        .logo { display: inline-flex; align-items: center; gap: 12px; text-decoration: none; }
        .logo img { display: block; height: 36px; width: auto; max-width: 160px; object-fit: contain; flex-shrink: 0; }
        .logo span { display: inline-block; font-size: 20px; font-weight: 800; line-height: 1; color: var(--primary); white-space: nowrap; }
        .desktop-nav { display: none; }
        @media (min-width: 992px) {
            .desktop-nav { display: block; flex: 1; margin: 0 40px; }
            .desktop-nav ul { display: flex; gap: 24px; align-items: center; }
            .desktop-nav a { font-weight: 500; font-size: 15px; padding: 8px 0; position: relative; }
            .desktop-nav a:hover { color: var(--primary); }
            .desktop-nav a::after { content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px; background: var(--primary); transition: var(--transition); }
            .desktop-nav a:hover::after { width: 100%; }
        }
        .mobile-menu-btn { display: block; background: none; border: none; padding: 8px; cursor: pointer; color: var(--text-main); }
        .mobile-menu-btn svg { width: 24px; height: 24px; fill: currentColor; }
        @media (min-width: 992px) { .mobile-menu-btn { display: none; } }
        
        .mobile-drawer-overlay { position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 100; opacity: 0; visibility: hidden; transition: var(--transition); }
        .mobile-drawer-overlay.active { opacity: 1; visibility: visible; }
        .mobile-drawer { position: fixed; top: 0; left: -300px; width: 280px; height: 100%; background: var(--bg-white); z-index: 101; transition: var(--transition); display: flex; flex-direction: column; }
        .mobile-drawer.active { left: 0; }
        .drawer-header { display: flex; align-items: center; justify-content: space-between; padding: 20px; border-bottom: 1px solid var(--border-color); }
        .drawer-close-btn { background: none; border: none; font-size: 28px; color: var(--text-muted); cursor: pointer; }
        .drawer-body { flex: 1; overflow-y: auto; padding: 20px 0; }
        .drawer-body ul li a { display: block; padding: 12px 24px; font-weight: 500; border-bottom: 1px solid #f3f4f6; }

        
        .breadcrumb { display: flex; flex-wrap: wrap; gap: 8px; font-size: 14px; color: var(--text-muted); padding: 20px 0; align-items: center; border-bottom: 1px solid var(--border-color); margin-bottom: 30px; }
        .breadcrumb a { color: var(--primary); }
        .breadcrumb a:hover { text-decoration: underline; }
        .breadcrumb span.sep { color: #d1d5db; }

        .article-main { background: var(--bg-white); padding: 40px; border-radius: var(--radius-md); box-shadow: var(--shadow-sm); margin-bottom: 40px; }
        @media (max-width: 768px) { .article-main { padding: 20px; } }
        
        .article-header { margin-bottom: 30px; border-bottom: 1px solid var(--border-color); padding-bottom: 20px; }
        .article-title { font-size: 28px; font-weight: 800; color: var(--text-main); margin-bottom: 15px; line-height: 1.4; }
        @media (min-width: 768px) { .article-title { font-size: 34px; } }
        
        .article-meta { display: flex; flex-wrap: wrap; gap: 20px; font-size: 14px; color: var(--text-muted); align-items: center; }
        .meta-item { display: inline-flex; align-items: center; gap: 6px; }
        .meta-item svg { width: 16px; height: 16px; fill: currentColor; }
        .article-tags-head { margin-top: 15px; display: flex; flex-wrap: wrap; gap: 8px; }
        .article-tags-head a { display: inline-block; padding: 4px 10px; background: #f3f4f6; color: var(--primary); font-size: 13px; border-radius: 4px; transition: var(--transition); }
        .article-tags-head a:hover { background: var(--primary); color: #fff; }

        
        .article-content { font-size: 16px; color: var(--text-article); line-height: 1.8; overflow-wrap: break-word; }
        .article-content p { margin-bottom: 20px; }
        .article-content h2 { font-size: 22px; color: var(--text-main); margin: 40px 0 20px; padding-bottom: 10px; border-bottom: 1px solid var(--border-color); }
        .article-content h3 { font-size: 18px; margin: 30px 0 15px; color: var(--text-main); }
        .article-content img { max-width: 100%; height: auto; border-radius: 6px; margin: 20px auto; display: block; box-shadow: var(--shadow-sm); }
        .article-content ul, .article-content ol { margin: 0 0 20px 20px; padding-left: 20px; }
        .article-content li { margin-bottom: 10px; }
        .article-content blockquote { border-left: 4px solid var(--primary); background: #f9fafb; padding: 15px 20px; margin: 20px 0; color: #4b5563; font-style: italic; }
        .article-content a { color: var(--primary); text-decoration: underline; }

        
        .article-nav { display: grid; grid-template-columns: 1fr; gap: 20px; margin: 40px 0; border-top: 1px solid var(--border-color); padding-top: 20px; }
        @media (min-width: 640px) { .article-nav { grid-template-columns: 1fr 1fr; } }
        .nav-item { padding: 15px; background: #f9fafb; border-radius: var(--radius-md); transition: var(--transition); display: block; border: 1px solid transparent; }
        .nav-item:hover { background: var(--bg-white); border-color: var(--primary); box-shadow: var(--shadow-sm); }
        .nav-label { font-size: 12px; color: var(--text-muted); margin-bottom: 5px; display: block; }
        .nav-title { font-size: 15px; font-weight: 600; color: var(--text-main); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

        
        .related-sec { margin-bottom: 60px; }
        .related-sec h3 { font-size: 20px; border-left: 4px solid var(--primary); padding-left: 12px; margin-bottom: 24px; color: var(--text-main); }
        .related-grid { display: grid; grid-template-columns: 1fr; gap: 20px; }
        @media (min-width: 640px) { .related-grid { grid-template-columns: repeat(2, 1fr); } }
        @media (min-width: 992px) { .related-grid { grid-template-columns: repeat(3, 1fr); } }
        
        .rel-card { background: var(--bg-white); border: 1px solid var(--border-color); border-radius: var(--radius-md); overflow: hidden; display: flex; flex-direction: column; transition: var(--transition); }
        .rel-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-sm); border-color: var(--primary); }
        .rel-thumb { aspect-ratio: 16/9; overflow: hidden; background: #e5e7eb; }
        .rel-thumb img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.3s; }
        .rel-card:hover .rel-thumb img { transform: scale(1.05); }
        .rel-info { padding: 15px; flex: 1; display: flex; flex-direction: column; }
        .rel-title { font-size: 14px; font-weight: 700; line-height: 1.5; margin-bottom: 10px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
        .rel-meta { margin-top: auto; font-size: 12px; color: var(--text-muted); display: flex; justify-content: space-between; }

        
        .site-footer { background: #1f2937; color: #9ca3af; padding: 60px 0 20px; font-size: 14px; }
        .footer-grid { display: grid; grid-template-columns: 1fr; gap: 40px; margin-bottom: 40px; max-width:1200px; margin-left:auto; margin-right:auto; padding:0 20px;}
        @media (min-width: 768px) { .footer-grid { grid-template-columns: 2fr 1fr 1fr; } }
        .footer-brand .logo span { color: #fff; }
        .footer-desc { margin-top: 16px; line-height: 1.8; }
        .footer-nav h3, .footer-links h3 { color: #fff; font-size: 16px; font-weight: 600; margin-bottom: 20px; }
        .footer-nav ul, .footer-links ul { display: flex; flex-direction: column; gap: 12px; }
        .footer-nav a:hover, .footer-links a:hover { color: #fff; }
        .footer-bottom { border-top: 1px solid #374151; padding-top: 20px; text-align: center; display: flex; flex-direction: column; gap: 10px; align-items: center; max-width:1200px; margin:0 auto;}
        @media (min-width: 768px) { .footer-bottom { flex-direction: row; justify-content: space-between; } }
        .footer-bottom-links { display: flex; gap: 16px; }