/* ============================================
   爱智导航 - 体育外围平台 样式表
   Mobile-first, Dark Editorial Sports Theme
   ============================================ */

/* --- CSS Variables --- */
:root {
  --color-bg: #0d1117;
  --color-surface: #161b22;
  --color-border: #21262d;
  --color-text: #e6edf3;
  --color-muted: #8b949e;
  --color-accent: #10b981;
  --color-accent-hover: #059669;
  --color-accent-dim: rgba(16, 185, 129, 0.12);
  --color-nav-bg: #0d1117;
  --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Inter', 'Noto Sans SC', sans-serif;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.4);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.5);
  --max-width: 1200px;
  --nav-height: 64px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
a:hover { color: var(--color-accent); }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1rem;
}

/* --- Navigation --- */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-nav-bg);
  border-bottom: 1px solid var(--color-border);
  height: var(--nav-height);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
  gap: 1.5rem;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

.nav-logo img {
  height: 36px;
  width: auto;
}

.nav-logo-text {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-text);
  white-space: nowrap;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0;
  flex: 1;
  justify-content: center;
}

.nav-links a {
  display: flex;
  align-items: center;
  padding: 0.5rem 1rem;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--color-muted);
  transition: color 0.2s;
  white-space: nowrap;
  border-bottom: 2px solid transparent;
  height: var(--nav-height);
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

.nav-cta {
  background: var(--color-accent);
  color: #fff;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  transition: background 0.2s;
}

.nav-cta:hover {
  background: var(--color-accent-hover);
  color: #fff;
}

/* Mobile menu */
.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.nav-hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}

.mobile-menu {
  display: none;
  position: fixed;
  top: var(--nav-height);
  left: 0;
  right: 0;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: 1rem;
  z-index: 99;
}

.mobile-menu.open { display: block; }

.mobile-menu a {
  display: block;
  padding: 0.75rem 0;
  color: var(--color-muted);
  font-size: 1rem;
  border-bottom: 1px solid var(--color-border);
}

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

/* --- Hero Section --- */
.hero {
  position: relative;
  min-height: 480px;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.3;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(13,17,23,0.85) 0%, rgba(13,17,23,0.5) 100%);
}

.hero-content {
  position: relative;
  z-index: 2;
  padding: 3rem 0;
}

.hero-eyebrow {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 1rem;
  border: 1px solid var(--color-accent);
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-sm);
}

.hero h1 {
  font-size: clamp(1.75rem, 4vw, 3rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
  max-width: 600px;
}

.hero h1 em {
  font-style: normal;
  color: var(--color-accent);
}

.hero-desc {
  font-size: 1.0625rem;
  color: var(--color-muted);
  max-width: 500px;
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.btn-primary {
  background: var(--color-accent);
  color: #fff;
  padding: 0.625rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9375rem;
  transition: background 0.2s;
  border: none;
  cursor: pointer;
}

.btn-primary:hover { background: var(--color-accent-hover); color: #fff; }

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  padding: 0.625rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-size: 0.9375rem;
  border: 1px solid var(--color-border);
  transition: border-color 0.2s, color 0.2s;
}

.btn-secondary:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* --- Section Layout --- */
.section {
  padding: 3rem 0;
}

.section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 1.5rem;
  gap: 1rem;
}

.section-title {
  font-size: 1.375rem;
  font-weight: 700;
  color: var(--color-text);
}

.section-title span {
  color: var(--color-accent);
}

.section-more {
  font-size: 0.875rem;
  color: var(--color-muted);
  white-space: nowrap;
  transition: color 0.2s;
}

.section-more:hover { color: var(--color-accent); }

/* --- News / Article Cards --- */
.article-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
}

.article-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s, transform 0.2s;
  display: flex;
  flex-direction: column;
}

.article-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-2px);
}

.article-card-img {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
}

.article-card-body {
  padding: 1rem;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.article-card-meta {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.article-card-category {
  font-size: 0.6875rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  background: var(--color-accent-dim);
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-sm);
}

.article-card-date {
  font-size: 0.75rem;
  color: var(--color-muted);
}

.article-card h3 {
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.4;
  margin-bottom: 0.5rem;
  color: var(--color-text);
}

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

.article-card-excerpt {
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-card-footer {
  margin-top: 0.75rem;
  padding-top: 0.75rem;
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.read-more {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-accent);
  transition: opacity 0.2s;
}

.read-more:hover { opacity: 0.8; }

/* --- List Layout (for category pages) --- */
.article-list { display: flex; flex-direction: column; gap: 1rem; }

.article-list-item {
  display: flex;
  gap: 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s;
}

.article-list-item:hover { border-color: var(--color-accent); }

.article-list-item-img {
  width: 160px;
  flex-shrink: 0;
  object-fit: cover;
}

.article-list-item-body {
  padding: 1rem;
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.article-list-item h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.375rem;
  line-height: 1.4;
}

.article-list-item h3 a:hover { color: var(--color-accent); }

.article-list-item-excerpt {
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* --- Feature / Stats Strip --- */
.stats-strip {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  padding: 1.5rem 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: 1rem;
  text-align: center;
}

.stat-item {}

.stat-number {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 0.25rem;
}

.stat-label {
  font-size: 0.8125rem;
  color: var(--color-muted);
}

/* --- Category Nav (homepage) --- */
.category-nav {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-bottom: 2rem;
}

.cat-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  padding: 1.25rem 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  text-align: center;
  transition: border-color 0.2s, background 0.2s;
}

.cat-btn:hover {
  border-color: var(--color-accent);
  background: var(--color-accent-dim);
  color: var(--color-accent);
}

.cat-icon {
  font-size: 1.75rem;
  line-height: 1;
}

.cat-name {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
}

.cat-count {
  font-size: 0.75rem;
  color: var(--color-muted);
}

/* --- Article Page Layout --- */
.page-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 2rem;
  align-items: start;
  padding: 2rem 0;
}

.article-main {}

.article-header {
  margin-bottom: 1.5rem;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
  color: var(--color-muted);
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.breadcrumb a { color: var(--color-muted); }
.breadcrumb a:hover { color: var(--color-accent); }
.breadcrumb-sep { color: var(--color-border); }

.article-header h1 {
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 1rem;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.8125rem;
  color: var(--color-muted);
  flex-wrap: wrap;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 1.5rem;
}

.article-body {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--color-text);
}

.article-body p { margin-bottom: 1.25rem; }

.article-body h2 {
  font-size: 1.375rem;
  font-weight: 700;
  margin: 2rem 0 1rem;
  color: var(--color-text);
  border-left: 3px solid var(--color-accent);
  padding-left: 0.75rem;
}

.article-body h3 {
  font-size: 1.125rem;
  font-weight: 700;
  margin: 1.5rem 0 0.75rem;
}

.article-body ul, .article-body ol {
  margin: 1rem 0 1.25rem 1.5rem;
  list-style: disc;
}

.article-body li { margin-bottom: 0.5rem; }

.article-body strong { color: var(--color-accent); font-weight: 600; }

.article-figure {
  margin: 1.5rem 0;
}

.article-figure img {
  width: 100%;
  border-radius: var(--radius-md);
}

.article-figure figcaption {
  font-size: 0.8125rem;
  color: var(--color-muted);
  text-align: center;
  margin-top: 0.5rem;
}

.article-split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  margin: 1.5rem 0;
  align-items: center;
}

.article-split.reverse { direction: rtl; }
.article-split.reverse > * { direction: ltr; }

/* --- Sidebar / Related Articles --- */
.sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 1rem);
}

.sidebar-widget {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  margin-bottom: 1.25rem;
}

.sidebar-title {
  font-size: 0.9375rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--color-text);
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-border);
}

.related-list { display: flex; flex-direction: column; gap: 0.75rem; }

.related-item {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.related-item-img {
  width: 60px;
  height: 45px;
  object-fit: cover;
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.related-item h4 {
  font-size: 0.8125rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--color-text);
}

.related-item h4 a:hover { color: var(--color-accent); }

.related-item-date {
  font-size: 0.6875rem;
  color: var(--color-muted);
  margin-top: 0.25rem;
}

/* --- About / CTA Section --- */
.cta-section {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  text-align: center;
  margin: 2rem 0;
}

.cta-section h2 {
  font-size: 1.5rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
}

.cta-section p {
  color: var(--color-muted);
  margin-bottom: 1.5rem;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

/* --- Footer --- */
.site-footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: 2.5rem 0 1.5rem;
  margin-top: 3rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr repeat(3, 1fr);
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-brand {}

.footer-brand img {
  height: 32px;
  margin-bottom: 0.75rem;
}

.footer-brand p {
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
  max-width: 260px;
}

.footer-col-title {
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text);
  margin-bottom: 0.75rem;
}

.footer-col ul { display: flex; flex-direction: column; gap: 0.4rem; }

.footer-col li a {
  font-size: 0.875rem;
  color: var(--color-muted);
  transition: color 0.2s;
}

.footer-col li a:hover { color: var(--color-accent); }

.footer-bottom {
  border-top: 1px solid var(--color-border);
  padding-top: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.footer-copy {
  font-size: 0.8125rem;
  color: var(--color-muted);
}

/* --- FAQ --- */
.faq-item {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  background: var(--color-surface);
  border: none;
  padding: 1rem 1.25rem;
  text-align: left;
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  transition: background 0.2s;
}

.faq-question:hover { background: var(--color-accent-dim); }

.faq-icon { transition: transform 0.3s; flex-shrink: 0; }
.faq-item.open .faq-icon { transform: rotate(45deg); }

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s;
}

.faq-item.open .faq-answer { max-height: 400px; }

.faq-answer-inner {
  padding: 0 1.25rem 1rem;
  font-size: 0.9375rem;
  color: var(--color-muted);
  line-height: 1.7;
}

/* --- Responsive --- */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-hamburger { display: flex; }
  .hero { min-height: 360px; }
  .article-grid { grid-template-columns: 1fr; }
  .article-list-item { flex-direction: column; }
  .article-list-item-img { width: 100%; height: 180px; }
  .page-layout { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .category-nav { grid-template-columns: repeat(3, 1fr); gap: 0.5rem; }
  .article-split { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn-primary,
  .hero-actions .btn-secondary { width: 100%; text-align: center; }
}

@media (max-width: 480px) {
  .footer-grid { grid-template-columns: 1fr; }
  .category-nav { grid-template-columns: 1fr 1fr; }
}

/* --- Utility --- */
.text-accent { color: var(--color-accent); }
.text-muted { color: var(--color-muted); }
.font-bold { font-weight: 700; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mb-2 { margin-bottom: 1rem; }