/* ============================================
   ChinaDiscern - Global Styles
   A clean, editorial design for analytical content
   ============================================ */

/* CSS Variables */
:root {
  --color-primary: #1a1a2e;
  --color-accent: #c0392b;
  --color-accent-hover: #a93226;
  --color-text: #2c3e50;
  --color-text-light: #6c757d;
  --color-bg: #ffffff;
  --color-bg-alt: #f8f9fa;
  --color-border: #e9ecef;
  --color-card-shadow: rgba(0, 0, 0, 0.08);
  --font-heading: 'Georgia', 'Times New Roman', serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --max-width: 1200px;
  --content-width: 780px;
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.7;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--color-accent-hover);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ============================================
   Header / Navigation
   ============================================ */
.site-header {
  background: var(--color-primary);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.site-logo {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: #fff;
  letter-spacing: 0.5px;
}

.site-logo span {
  color: var(--color-accent);
}

.site-logo:hover {
  color: #fff;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: #fff;
  margin: 5px 0;
  transition: all 0.3s ease;
}

.main-nav ul {
  list-style: none;
  display: flex;
  gap: 32px;
  align-items: center;
}

.main-nav a {
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.3px;
  text-transform: uppercase;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
  transition: all 0.2s ease;
}

.main-nav a:hover,
.main-nav a.active {
  color: #fff;
  border-bottom-color: var(--color-accent);
}

/* ============================================
   Hero Section (Homepage)
   ============================================ */
.hero {
  position: relative;
  height: 520px;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #fff;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  filter: brightness(0.4);
  z-index: 0;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 720px;
  padding: 0 24px;
}

.hero h1 {
  font-family: var(--font-heading);
  font-size: 3rem;
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 16px;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.hero p {
  font-size: 1.15rem;
  opacity: 0.9;
  line-height: 1.6;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.2);
}

/* ============================================
   Main Content Layout
   ============================================ */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.content-wrapper {
  padding: 60px 0;
}

.section-title {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  color: var(--color-primary);
  margin-bottom: 36px;
  padding-bottom: 12px;
  border-bottom: 3px solid var(--color-accent);
  display: inline-block;
}

/* ============================================
   Article Cards Grid (Homepage)
   ============================================ */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 32px;
}

.article-card {
  background: var(--color-bg);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 12px var(--color-card-shadow);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.article-card a {
  color: inherit;
}

.card-image {
  width: 100%;
  height: 220px;
  object-fit: cover;
}

.card-body {
  padding: 24px;
}

.card-category {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--color-accent);
  margin-bottom: 10px;
}

.card-title {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.35;
  margin-bottom: 12px;
}

.card-title a:hover {
  color: var(--color-accent);
}

.card-excerpt {
  font-size: 0.925rem;
  color: var(--color-text-light);
  line-height: 1.6;
  margin-bottom: 16px;
}

.card-meta {
  font-size: 0.8rem;
  color: var(--color-text-light);
  padding-top: 12px;
  border-top: 1px solid var(--color-border);
}

/* ============================================
   Article Page
   ============================================ */
.article-header {
  text-align: center;
  padding: 48px 24px 32px;
  max-width: var(--content-width);
  margin: 0 auto;
}

.article-header .card-category {
  font-size: 0.8rem;
  margin-bottom: 16px;
}

.article-header h1 {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.25;
  margin-bottom: 16px;
}

.article-meta {
  font-size: 0.9rem;
  color: var(--color-text-light);
}

.article-meta time {
  font-weight: 500;
}

.article-hero-image {
  max-width: 960px;
  margin: 0 auto 40px;
  border-radius: 8px;
  overflow: hidden;
}

.article-hero-image img {
  width: 100%;
  height: 480px;
  object-fit: cover;
}

.article-hero-image figcaption {
  font-size: 0.8rem;
  color: var(--color-text-light);
  text-align: center;
  padding: 8px 16px;
  background: var(--color-bg-alt);
}

.article-content {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 24px 60px;
}

.article-content h2 {
  font-family: var(--font-heading);
  font-size: 1.6rem;
  color: var(--color-primary);
  margin: 40px 0 16px;
  line-height: 1.3;
}

.article-content h3 {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  color: var(--color-primary);
  margin: 32px 0 12px;
}

.article-content p {
  margin-bottom: 20px;
  font-size: 1.05rem;
  line-height: 1.8;
}

.article-content blockquote {
  border-left: 4px solid var(--color-accent);
  margin: 28px 0;
  padding: 16px 24px;
  background: var(--color-bg-alt);
  font-style: italic;
  color: var(--color-text-light);
  border-radius: 0 4px 4px 0;
}

.article-content ul,
.article-content ol {
  margin: 16px 0 20px 24px;
}

.article-content li {
  margin-bottom: 8px;
  font-size: 1.05rem;
  line-height: 1.7;
}

.article-content strong {
  color: var(--color-primary);
}

/* Tags */
.article-tags {
  margin-top: 40px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
}

.article-tags span {
  display: inline-block;
  background: var(--color-bg-alt);
  color: var(--color-text-light);
  font-size: 0.8rem;
  padding: 4px 12px;
  border-radius: 20px;
  margin: 4px 4px 4px 0;
}

/* ============================================
   About / Static Pages
   ============================================ */
.page-header {
  background: var(--color-primary);
  color: #fff;
  text-align: center;
  padding: 60px 24px;
}

.page-header h1 {
  font-family: var(--font-heading);
  font-size: 2.25rem;
  margin-bottom: 12px;
}

.page-header p {
  font-size: 1.05rem;
  opacity: 0.85;
  max-width: 600px;
  margin: 0 auto;
}

.page-content {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 48px 24px 60px;
}

.page-content h2 {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  color: var(--color-primary);
  margin: 36px 0 16px;
}

.page-content h3 {
  font-size: 1.15rem;
  color: var(--color-primary);
  margin: 24px 0 12px;
}

.page-content p {
  margin-bottom: 18px;
  font-size: 1.02rem;
  line-height: 1.75;
}

.page-content ul, .page-content ol {
  margin: 12px 0 18px 24px;
}

.page-content li {
  margin-bottom: 6px;
  line-height: 1.7;
}

.contact-email {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-bg-alt);
  padding: 12px 20px;
  border-radius: 8px;
  font-size: 1rem;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.contact-email svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

/* ============================================
   Footer
   ============================================ */
.site-footer {
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.75);
  padding: 48px 24px 32px;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
}

.footer-about h3,
.footer-links h3 {
  color: #fff;
  font-family: var(--font-heading);
  font-size: 1.1rem;
  margin-bottom: 16px;
}

.footer-about p {
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 12px;
}

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

.footer-links a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  line-height: 2;
}

.footer-links a:hover {
  color: #fff;
}

.footer-bottom {
  max-width: var(--max-width);
  margin: 32px auto 0;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
  font-size: 0.8rem;
}

/* ============================================
   Google AdSense Placeholder
   ============================================ */
.ad-placeholder {
  background: var(--color-bg-alt);
  border: 1px dashed var(--color-border);
  text-align: center;
  padding: 20px;
  margin: 32px 0;
  color: var(--color-text-light);
  font-size: 0.85rem;
  border-radius: 4px;
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 992px) {
  .footer-inner {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: block;
  }

  .main-nav {
    display: none;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--color-primary);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  }

  .main-nav.open {
    display: block;
  }

  .main-nav ul {
    flex-direction: column;
    gap: 0;
    padding: 8px 0;
  }

  .main-nav li {
    width: 100%;
  }

  .main-nav a {
    display: block;
    padding: 12px 24px;
    border-bottom: none;
  }

  .main-nav a:hover {
    background: rgba(255, 255, 255, 0.05);
    border-bottom: none;
  }

  .hero {
    height: 400px;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .articles-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .article-header h1 {
    font-size: 1.75rem;
  }

  .article-hero-image img {
    height: 280px;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .page-header {
    padding: 40px 24px;
  }

  .page-header h1 {
    font-size: 1.75rem;
  }
}

@media (max-width: 480px) {
  .header-inner {
    padding: 0 16px;
  }

  .hero {
    height: 340px;
  }

  .hero h1 {
    font-size: 1.6rem;
  }

  .hero p {
    font-size: 0.95rem;
  }

  .content-wrapper {
    padding: 40px 0;
  }

  .container {
    padding: 0 16px;
  }

  .card-body {
    padding: 16px;
  }

  .article-content p,
  .article-content li {
    font-size: 1rem;
  }
}

/* ============================================
   Utility Classes
   ============================================ */
.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;
}

.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* ============================================
   Pagination
   ============================================ */
.pagination {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--color-border);
}

.pagination button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 12px;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  color: var(--color-text);
  font-size: 0.9rem;
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.pagination button:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background: #fff;
}

.pagination button.active {
  background: var(--color-accent);
  color: #fff;
  border-color: var(--color-accent);
  font-weight: 600;
}

.pagination button:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.pagination button:disabled:hover {
  border-color: var(--color-border);
  color: var(--color-text);
  background: var(--color-bg);
}

/* ============================================
   Related Articles (Article Detail Page)
   ============================================ */
.related-articles {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 24px 60px;
}

.related-articles h2 {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  color: var(--color-primary);
  margin-bottom: 28px;
  padding-bottom: 12px;
  border-bottom: 3px solid var(--color-accent);
  display: inline-block;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 20px;
}

.related-card {
  background: var(--color-bg);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 2px 10px var(--color-card-shadow);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.related-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.1);
}

.related-card img {
  width: 100%;
  height: 140px;
  object-fit: cover;
}

.related-card-body {
  padding: 14px;
}

.related-card-body .card-category {
  font-size: 0.7rem;
  margin-bottom: 6px;
}

.related-card-body h3 {
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--color-primary);
}

.related-card-body h3 a {
  color: inherit;
}

.related-card-body h3 a:hover {
  color: var(--color-accent);
}

@media (max-width: 768px) {
  .related-grid {
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }
}

@media (max-width: 480px) {
  .related-grid {
    grid-template-columns: 1fr;
  }
  .pagination button {
    min-width: 36px;
    height: 36px;
    font-size: 0.85rem;
  }
}