/* CSS Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif; line-height: 1.6; color: #333; background: #f8f9fa; }
a { color: #0066cc; text-decoration: none; transition: color 0.3s; }
a:hover { color: #004499; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

/* Container */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header { background: #fff; box-shadow: 0 2px 8px rgba(0,0,0,0.08); position: sticky; top: 0; z-index: 1000; }
.main-nav { display: flex; align-items: center; justify-content: space-between; padding: 15px 0; }
.logo img { height: 40px; width: auto; }
.nav-links { display: flex; gap: 30px; }
.nav-links a { color: #333; font-weight: 500; padding: 5px 0; border-bottom: 2px solid transparent; }
.nav-links a:hover { color: #0066cc; border-bottom-color: #0066cc; }

/* Hero */
.hero { background: linear-gradient(135deg, #0066cc 0%, #004499 100%); color: #fff; padding: 80px 0; }
.hero .container { display: flex; align-items: center; gap: 60px; }
.hero-content { flex: 1; }
.hero h1 { font-size: 2.8rem; margin-bottom: 20px; line-height: 1.2; }
.hero-subtitle { font-size: 1.2rem; opacity: 0.9; margin-bottom: 40px; }
.hero-stats { display: flex; gap: 40px; }
.stat-item { text-align: center; }
.stat-num { display: block; font-size: 2rem; font-weight: 700; }
.stat-label { font-size: 0.9rem; opacity: 0.8; }
.hero-image { flex: 1; }
.hero-image img { border-radius: 12px; box-shadow: 0 20px 40px rgba(0,0,0,0.2); }

/* Features */
.features { padding: 80px 0; background: #fff; }
.features h2, .categories h2, .latest-articles h2, .about-section h2, .stats-section h2, .testimonials h2, .cta-section h2 { text-align: center; font-size: 2rem; margin-bottom: 50px; color: #1a1a1a; }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.feature-card { text-align: center; padding: 30px; background: #f8f9fa; border-radius: 12px; transition: transform 0.3s, box-shadow 0.3s; }
.feature-card:hover { transform: translateY(-5px); box-shadow: 0 10px 30px rgba(0,0,0,0.1); }
.feature-card img { width: 100%; height: 180px; object-fit: cover; border-radius: 8px; margin-bottom: 20px; }
.feature-card h3 { font-size: 1.3rem; margin-bottom: 15px; color: #1a1a1a; }
.feature-card p { color: #666; }

/* Categories */
.categories { padding: 80px 0; background: #f0f4f8; }
.categories-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.category-card { background: #fff; padding: 40px 30px; border-radius: 12px; text-align: center; transition: all 0.3s; border: 2px solid transparent; }
.category-card:hover { border-color: #0066cc; transform: translateY(-5px); }
.category-card h3 { font-size: 1.5rem; color: #0066cc; margin-bottom: 15px; }
.category-card p { color: #666; margin-bottom: 20px; }
.category-card .arrow { color: #0066cc; font-weight: 500; }

/* Articles */
.latest-articles { padding: 80px 0; background: #fff; }
.articles-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.article-card { background: #fff; border-radius: 12px; overflow: hidden; box-shadow: 0 4px 15px rgba(0,0,0,0.08); transition: transform 0.3s; }
.article-card:hover { transform: translateY(-5px); }
.article-card img { width: 100%; height: 200px; object-fit: cover; }
.article-content { padding: 25px; }
.article-category { display: inline-block; background: #e6f0ff; color: #0066cc; padding: 4px 12px; border-radius: 20px; font-size: 0.85rem; margin-bottom: 12px; }
.article-card h3 { font-size: 1.2rem; margin-bottom: 12px; line-height: 1.4; }
.article-card h3 a { color: #1a1a1a; }
.article-card h3 a:hover { color: #0066cc; }
.article-card p { color: #666; font-size: 0.95rem; margin-bottom: 15px; }
.read-more { display: inline-block; color: #0066cc; font-weight: 500; }
.view-all { text-align: center; margin-top: 40px; }
.btn-secondary { display: inline-block; padding: 12px 30px; background: #0066cc; color: #fff; border-radius: 8px; font-weight: 500; transition: background 0.3s; }
.btn-secondary:hover { background: #004499; color: #fff; }

/* About Section */
.about-section { padding: 80px 0; background: #f8f9fa; }
.about-content { display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center; }
.about-text h3 { font-size: 1.5rem; margin-bottom: 20px; color: #1a1a1a; }
.about-text p { color: #666; margin-bottom: 15px; line-height: 1.8; }
.about-image img { border-radius: 12px; box-shadow: 0 10px 30px rgba(0,0,0,0.1); }

/* Stats Section */
.stats-section { padding: 60px 0; background: linear-gradient(135deg, #0066cc 0%, #004499 100%); color: #fff; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 30px; text-align: center; }
.stats-item .stats-num { display: block; font-size: 2.5rem; font-weight: 700; margin-bottom: 10px; }
.stats-item .stats-label { font-size: 1rem; opacity: 0.9; }

/* Testimonials */
.testimonials { padding: 80px 0; background: #fff; }
.testimonials-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
.testimonial-card { background: #f8f9fa; padding: 30px; border-radius: 12px; }
.testimonial-card p { color: #666; font-style: italic; margin-bottom: 20px; line-height: 1.8; }
.testimonial-author { display: flex; align-items: center; gap: 15px; }
.testimonial-author img { width: 50px; height: 50px; border-radius: 50%; object-fit: cover; }
.testimonial-author .author-info h4 { font-size: 1rem; color: #1a1a1a; margin-bottom: 5px; }
.testimonial-author .author-info span { font-size: 0.85rem; color: #999; }

/* CTA Section */
.cta-section { padding: 80px 0; background: #f0f4f8; text-align: center; }
.cta-section p { color: #666; font-size: 1.1rem; margin-bottom: 30px; max-width: 600px; margin-left: auto; margin-right: auto; }
.btn-primary { display: inline-block; padding: 15px 40px; background: #0066cc; color: #fff; border-radius: 8px; font-weight: 600; transition: background 0.3s; margin: 0 10px; }
.btn-primary:hover { background: #004499; color: #fff; }

/* Newsletter */
.newsletter { padding: 60px 0; background: linear-gradient(135deg, #0066cc 0%, #004499 100%); color: #fff; text-align: center; }
.newsletter h2 { color: #fff; margin-bottom: 15px; }
.newsletter p { opacity: 0.9; margin-bottom: 30px; }
.newsletter-form { display: flex; justify-content: center; gap: 15px; max-width: 500px; margin: 0 auto; }
.newsletter-form input { flex: 1; padding: 12px 20px; border: none; border-radius: 8px; font-size: 1rem; }
.newsletter-form button { padding: 12px 30px; background: #fff; color: #0066cc; border: none; border-radius: 8px; font-weight: 600; cursor: pointer; transition: background 0.3s; }
.newsletter-form button:hover { background: #f0f0f0; }

/* Footer */
.site-footer { background: #1a1a1a; color: #fff; padding: 60px 0 20px; }
.footer-content { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-section h4 { font-size: 1.2rem; margin-bottom: 20px; color: #fff; }
.footer-logo { height: 40px; margin-bottom: 15px; filter: brightness(0) invert(1); }
.footer-section p { color: #aaa; line-height: 1.8; }
.footer-section ul li { margin-bottom: 10px; }
.footer-section a { color: #aaa; }
.footer-section a:hover { color: #fff; }
.footer-bottom { text-align: center; padding-top: 20px; border-top: 1px solid #333; color: #666; }

/* Category & Article Pages */
.page-header { background: linear-gradient(135deg, #0066cc 0%, #004499 100%); color: #fff; padding: 60px 0; text-align: center; }
.page-header h1 { font-size: 2.2rem; margin-bottom: 15px; }
.page-header p { opacity: 0.9; }
.page-content { padding: 60px 0; }
.doc-layout { display: grid; grid-template-columns: 250px 1fr 280px; gap: 40px; }
.doc-sidebar { position: sticky; top: 100px; height: fit-content; }
.doc-toc { background: #fff; padding: 25px; border-radius: 12px; box-shadow: 0 4px 15px rgba(0,0,0,0.08); }
.doc-toc h4 { font-size: 1rem; margin-bottom: 15px; color: #1a1a1a; padding-bottom: 10px; border-bottom: 2px solid #0066cc; }
.doc-toc ul li { margin-bottom: 10px; }
.doc-toc a { color: #666; font-size: 0.95rem; display: block; padding: 5px 0; transition: color 0.2s; }
.doc-toc a:hover { color: #0066cc; }
.doc-article { background: #fff; padding: 40px; border-radius: 12px; box-shadow: 0 4px 15px rgba(0,0,0,0.08); }
.doc-article h2 { font-size: 1.8rem; margin: 30px 0 20px; color: #1a1a1a; border-bottom: 2px solid #f0f0f0; padding-bottom: 10px; }
.doc-article h2:first-child { margin-top: 0; }
.doc-article p { margin-bottom: 20px; line-height: 1.8; color: #444; }
.doc-article ul, .doc-article ol { margin: 20px 0; padding-left: 30px; }
.doc-article li { margin-bottom: 10px; color: #444; }
.doc-article img { max-width: 100%; border-radius: 8px; margin: 20px 0; }
.related-sidebar { position: sticky; top: 100px; height: fit-content; }
.related-box { background: #fff; padding: 25px; border-radius: 12px; box-shadow: 0 4px 15px rgba(0,0,0,0.08); }
.related-box h4 { font-size: 1rem; margin-bottom: 15px; color: #1a1a1a; padding-bottom: 10px; border-bottom: 2px solid #0066cc; }
.related-box ul li { margin-bottom: 12px; }
.related-box a { color: #666; font-size: 0.95rem; display: block; padding: 8px 0; border-left: 3px solid transparent; padding-left: 10px; transition: all 0.2s; }
.related-box a:hover { color: #0066cc; border-left-color: #0066cc; }
.category-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 25px; }
.category-list-item { background: #fff; border-radius: 12px; overflow: hidden; box-shadow: 0 4px 15px rgba(0,0,0,0.08); transition: transform 0.3s; }
.category-list-item:hover { transform: translateY(-5px); }
.category-list-item img { width: 100%; height: 180px; object-fit: cover; }
.category-list-item .item-content { padding: 20px; }
.category-list-item h3 { font-size: 1.1rem; margin-bottom: 10px; }
.category-list-item h3 a { color: #1a1a1a; }
.category-list-item p { color: #666; font-size: 0.9rem; }

/* Utilities */
.visually-hidden { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

.related-sidebar a.related-link { display: block; color: #666; font-size: 0.95rem; padding: 8px 0; border-left: 3px solid transparent; padding-left: 10px; transition: all 0.2s; margin-bottom: 12px; }
.related-sidebar a.related-link:hover { color: #0066cc; border-left-color: #0066cc; }
.related-sidebar h4 { font-size: 1rem; margin-bottom: 15px; color: #1a1a1a; padding-bottom: 10px; border-bottom: 2px solid #0066cc; }
.related-sidebar a:not(.related-link) { display: block; color: #666; font-size: 0.95rem; padding: 8px 0; border-left: 3px solid transparent; padding-left: 10px; transition: all 0.2s; margin-bottom: 12px; }
.related-sidebar a:not(.related-link):hover { color: #0066cc; border-left-color: #0066cc; }
.related-sidebar ul { list-style: none; }
.related-sidebar ul li a { display: block; color: #666; font-size: 0.95rem; padding: 8px 0; border-left: 3px solid transparent; padding-left: 10px; transition: all 0.2s; }
.related-sidebar ul li a:hover { color: #0066cc; border-left-color: #0066cc; }
.breadcrumb-nav { font-size: 0.9rem; color: #666; margin-bottom: 20px; }
.breadcrumb-nav a { color: #0066cc; }
.breadcrumb-nav a:hover { text-decoration: underline; }
.breadcrumb-nav span { color: #999; }

/* Responsive */
@media (max-width: 1024px) {
  .hero .container { flex-direction: column; text-align: center; }
  .hero-stats { justify-content: center; }
  .features-grid, .categories-grid, .articles-grid { grid-template-columns: repeat(2, 1fr); }
  .doc-layout { grid-template-columns: 1fr; }
  .doc-sidebar, .related-sidebar { position: static; }
  .footer-content { grid-template-columns: 1fr 1fr; }
  .about-content { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .testimonials-grid { grid-template-columns: 1fr; }
}
@media (max-width: 768px) {
  .main-nav { flex-direction: column; gap: 15px; }
  .nav-links { flex-wrap: wrap; justify-content: center; }
  .hero h1 { font-size: 2rem; }
  .features-grid, .categories-grid, .articles-grid { grid-template-columns: 1fr; }
  .category-list { grid-template-columns: 1fr; }
  .footer-content { grid-template-columns: 1fr; }
  .newsletter-form { flex-direction: column; }
  .stats-grid { grid-template-columns: 1fr 1fr; }
}