/* 白月光 (bygjc.xyz) - Global Styling */
:root {
  --primary-color: #6c47ff;
  --primary-hover: #5935ed;
  --primary-light: #f0ecff;
  --text-dark: #1e293b;
  --text-muted: #64748b;
  --text-light: #94a3b8;
  --bg-light: #f8fafc;
  --bg-white: #ffffff;
  --card-bg: #ffffff;
  --border-color: #e2e8f0;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 10px 25px rgba(108,71,255,0.12);
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text-dark);
  background-color: #f8fafc;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

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

/* Header Navbar */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border-color);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-dark);
  white-space: nowrap;
  flex-shrink: 0;
}

.brand-logo img {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  object-fit: cover;
  flex-shrink: 0;
}

.brand-title {
  display: flex;
  align-items: baseline;
  gap: 6px;
  white-space: nowrap;
  flex-shrink: 0;
}

.brand-title span {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-weight: 400;
  white-space: nowrap;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 20px;
  white-space: nowrap;
  flex-shrink: 0;
}

.nav-link {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: color 0.2s;
  white-space: nowrap;
  flex-shrink: 0;
}

.nav-link:hover {
  color: var(--primary-color);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
  white-space: nowrap;
  flex-shrink: 0;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: 8px;
  transition: all 0.2s ease;
  cursor: pointer;
  border: none;
  white-space: nowrap;
  flex-shrink: 0;
}

.btn-sm {
  padding: 8px 14px;
  font-size: 0.88rem;
}

.btn-outline {
  background: transparent;
  color: var(--text-dark);
  border: 1px solid var(--border-color);
}

.btn-outline:hover {
  background: var(--bg-light);
  border-color: var(--text-muted);
}

.btn-primary {
  background-color: var(--primary-color);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: var(--primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-recommend {
  background-color: #f1f5f9;
  color: #475569;
  border: 1px solid #cbd5e1;
}

.btn-recommend:hover {
  background-color: #e2e8f0;
  color: var(--primary-color);
}

/* Hero Section (Matching Image: Enterprise BGP Purple Box) */
.hero-banner-section {
  padding: 40px 0;
}

.hero-bg-card {
  background: linear-gradient(135deg, #6c47ff 0%, #5b36f5 50%, #4724d6 100%);
  border-radius: var(--radius-xl);
  padding: 80px 40px;
  text-align: center;
  color: #ffffff;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.hero-bg-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -20%;
  width: 140%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.12) 0%, rgba(255,255,255,0) 60%);
  pointer-events: none;
}

.hero-title {
  font-size: 2.75rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 16px;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: rgba(255, 255, 255, 0.88);
  margin-bottom: 36px;
  max-width: 700px;
  margin-left: auto;
  margin-right: auto;
}

.hero-buttons {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}

.btn-hero-white {
  background-color: #ffffff;
  color: var(--primary-color);
  font-weight: 700;
  padding: 12px 28px;
}

.btn-hero-white:hover {
  background-color: #f8fafc;
  color: var(--primary-hover);
  box-shadow: 0 4px 14px rgba(0,0,0,0.15);
}

.btn-hero-translucent {
  background-color: rgba(255, 255, 255, 0.2);
  color: #ffffff;
  backdrop-filter: blur(5px);
  padding: 12px 28px;
}

.btn-hero-translucent:hover {
  background-color: rgba(255, 255, 255, 0.3);
}

/* Sections General */
.section {
  padding: 60px 0;
}

.section-header {
  text-align: left;
  margin-bottom: 40px;
}

.section-tag {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 1px;
  color: var(--primary-color);
  text-transform: uppercase;
  margin-bottom: 8px;
  display: block;
}

.section-title {
  font-size: 1.85rem;
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 10px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
}

/* Core Abilities Grid (Matching Screenshot) */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  border: 1px solid var(--border-color);
  transition: all 0.3s ease;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: #cbd5e1;
}

.feature-icon-wrapper {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  margin-bottom: 24px;
}

.icon-purple {
  background-color: #eeddff;
  color: #7c3aed;
}

.icon-green {
  background-color: #dcfce7;
  color: #16a34a;
}

.icon-blue {
  background-color: #e0f2fe;
  color: #0284c7;
}

.icon-amber {
  background-color: #fef3c7;
  color: #d97706;
}

.feature-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 12px;
}

.feature-card-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* Pricing Section */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.pricing-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  border: 1px solid var(--border-color);
  position: relative;
  display: flex;
  flex-direction: column;
  transition: all 0.3s ease;
}

.pricing-card.popular {
  border: 2px solid var(--primary-color);
  box-shadow: var(--shadow-lg);
}

.popular-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--primary-color);
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: 20px;
  letter-spacing: 0.5px;
}

.plan-name {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 8px;
}

.plan-price {
  margin-bottom: 20px;
  display: flex;
  align-items: baseline;
  gap: 4px;
}

.price-currency {
  font-size: 1.2rem;
  font-weight: 700;
  color: var(--primary-color);
}

.price-num {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--text-dark);
}

.price-period {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.plan-features {
  list-style: none;
  margin-bottom: 28px;
  flex-grow: 1;
}

.plan-features li {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.plan-features li i {
  color: #10b981;
}

/* Latency Test Section */
.ping-test-box {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 30px;
  box-shadow: var(--shadow-sm);
}

.ping-table {
  width: 100%;
  border-collapse: collapse;
}

.ping-table th, .ping-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.ping-table th {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-muted);
  background: #f8fafc;
}

.ping-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 0.9rem;
}

.ping-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #10b981;
}

.ping-val {
  font-weight: 700;
  color: var(--primary-color);
  font-family: monospace;
}

/* Articles Section */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.article-card {
  background: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  transition: all 0.3s ease;
}

.article-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary-color);
}

.article-category {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.article-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-dark);
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-summary {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 20px;
  flex-grow: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.article-link {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary-color);
  display: flex;
  align-items: center;
  gap: 6px;
}

/* Reviews Section */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 28px;
}

.review-stars {
  color: #f59e0b;
  margin-bottom: 12px;
  font-size: 0.9rem;
}

.review-content {
  font-size: 0.95rem;
  color: var(--text-dark);
  margin-bottom: 20px;
  line-height: 1.6;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background: var(--primary-light);
  color: var(--primary-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1rem;
}

.author-info h4 {
  font-size: 0.95rem;
  font-weight: 700;
}

.author-info p {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* FAQ Accordion */
.faq-list {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.faq-item {
  background: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color 0.2s;
}

.faq-item.active {
  border-color: var(--primary-color);
}

.faq-header {
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 700;
  font-size: 1.05rem;
  color: var(--text-dark);
  user-select: none;
}

.faq-icon {
  transition: transform 0.3s ease;
  color: var(--text-muted);
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
  color: var(--primary-color);
}

.faq-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
  background: #fafbfc;
}

.faq-item.active .faq-body {
  max-height: 1000px;
  transition: max-height 0.3s cubic-bezier(1, 0, 1, 0);
}

.faq-content {
  padding: 0 24px 20px 24px;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* Footer Section & PBN Link Pipeline */
.site-footer {
  background-color: #0f172a;
  color: #94a3b8;
  padding-top: 60px;
  padding-bottom: 30px;
  font-size: 0.9rem;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand .brand-title {
  color: #ffffff;
}

.footer-brand p {
  margin-top: 16px;
  line-height: 1.7;
  max-width: 360px;
}

.footer-col h4 {
  color: #ffffff;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 20px;
}

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

.footer-col ul li {
  margin-bottom: 12px;
}

.footer-col ul li a {
  color: #94a3b8;
  transition: color 0.2s;
}

.footer-col ul li a:hover {
  color: #ffffff;
}

/* Task 2: PBN Friend Link Injection Area */
.footer-pbn-area {
  border-top: 1px solid #1e293b;
  padding: 20px 0;
  text-align: center;
}

.pbn-container {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  font-size: 0.85rem;
  color: #64748b;
}

.pbn-label {
  color: #94a3b8;
}

.pbn-link {
  color: #cbd5e1;
  text-decoration: none;
  font-size: 0.85rem;
  transition: color 0.2s;
}

.pbn-link:hover {
  color: #ffffff;
  text-decoration: underline;
}

.footer-bottom {
  border-top: 1px solid #1e293b;
  padding-top: 24px;
  text-align: center;
  font-size: 0.82rem;
  color: #64748b;
}

/* Article Detail Page Styles */
.article-header-section {
  background: var(--bg-white);
  padding: 50px 0 30px;
  border-bottom: 1px solid var(--border-color);
}

.breadcrumb {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.article-main-title {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--text-dark);
  margin-bottom: 16px;
  line-height: 1.3;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.article-body-layout {
  display: grid;
  grid-template-columns: 3fr 1fr;
  gap: 40px;
  padding: 50px 0;
}

.article-content-box {
  background: #ffffff;
  padding: 40px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
}

.article-content-box h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-dark);
  margin: 32px 0 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--primary-light);
}

.article-content-box h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-dark);
  margin: 24px 0 12px;
}

.article-content-box p {
  font-size: 1rem;
  color: #334155;
  line-height: 1.8;
  margin-bottom: 20px;
}

.article-content-box ul, .article-content-box ol {
  margin: 0 0 20px 24px;
  color: #334155;
  line-height: 1.8;
}

.article-content-box li {
  margin-bottom: 8px;
}

.article-content-box blockquote {
  background: var(--primary-light);
  border-left: 4px solid var(--primary-color);
  padding: 16px 20px;
  margin: 24px 0;
  border-radius: 0 8px 8px 0;
  color: var(--text-dark);
  font-weight: 500;
}

.article-sidebar {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.sidebar-widget {
  background: #ffffff;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px;
}

.widget-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 16px;
  color: var(--text-dark);
}

/* Responsive Media Queries */
@media (max-width: 1024px) {
  .features-grid, .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-grid, .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .article-body-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: 64px;
  }
  .nav-menu {
    display: none;
  }
  .hero-bg-card {
    padding: 40px 20px;
  }
  .hero-title {
    font-size: 1.85rem;
  }
  .features-grid, .pricing-grid, .articles-grid, .reviews-grid {
    grid-template-columns: 1fr;
  }
  .footer-top {
    grid-template-columns: 1fr;
  }
}