/* ==========================================================================
   FatCatCloud 肥猫机场 (fatcatcloud1.sbs) - 官方主样式表
   高性价比 4K/8K IPLC 专线科学上网落地页
   全端响应式 / 高级黑白极简极客美学 (Monochrome Edition)
   ========================================================================== */

:root {
  --bg-dark: #000000;
  --bg-card: #0d0d0d;
  --bg-card-hover: #171717;
  --bg-glass: rgba(13, 13, 13, 0.85);
  --border-color: rgba(255, 255, 255, 0.12);
  --border-focus: rgba(255, 255, 255, 0.45);

  --primary: #ffffff;
  --primary-hover: #e5e5e5;
  --cyan: #ffffff;
  --accent: #d4d4d4;
  --purple: #a3a3a3;
  --amber: #ffffff;
  --emerald: #ffffff;

  --text-main: #ffffff;
  --text-sub: #a3a3a3;
  --text-muted: #737373;

  --gradient-brand: linear-gradient(135deg, #ffffff 0%, #d4d4d4 50%, #888888 100%);
  --gradient-glow: radial-gradient(circle at 50% -20%, rgba(255, 255, 255, 0.12), transparent 70%);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.9);
  --shadow-glow: 0 0 25px rgba(255, 255, 255, 0.12);
}

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

html {
  scroll-behavior: smooth;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-main);
  line-height: 1.6;
}

body {
  overflow-x: hidden;
  background: var(--bg-dark);
  background-image: 
    radial-gradient(circle at 20% 10%, rgba(255, 255, 255, 0.04) 0%, transparent 40%),
    radial-gradient(circle at 80% 60%, rgba(255, 255, 255, 0.03) 0%, transparent 50%),
    radial-gradient(circle at 50% 90%, rgba(255, 255, 255, 0.02) 0%, transparent 50%);
  background-attachment: fixed;
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: all 0.25s ease;
}

a:hover {
  color: #a3a3a3;
}

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   Header & Navigation
   ========================================================================== */
.header-nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.88);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
  transition: all 0.3s ease;
}

.nav-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
}

.logo-link {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-img {
  width: 42px;
  height: 42px;
  filter: drop-shadow(0 0 8px rgba(255, 255, 255, 0.25));
}

.logo-text {
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-badge {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.08);
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.25);
  text-transform: uppercase;
}

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

.nav-links a {
  color: var(--text-sub);
  font-weight: 500;
  font-size: 0.95rem;
}

.nav-links a:hover {
  color: var(--text-main);
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: #ffffff;
  color: #000000 !important;
  font-weight: 700;
  font-size: 0.95rem;
  padding: 10px 24px;
  border-radius: var(--radius-md);
  border: 1px solid #ffffff;
  box-shadow: 0 4px 18px rgba(255, 255, 255, 0.2);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn-primary:hover {
  background: #e5e5e5;
  color: #000000 !important;
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(255, 255, 255, 0.35);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main) !important;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 10px 24px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  cursor: pointer;
  transition: all 0.3s ease;
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: #ffffff;
  transform: translateY(-2px);
}

.mobile-menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 1.25rem;
  cursor: pointer;
}

.mobile-nav-drawer {
  display: none;
  position: fixed;
  top: 76px;
  left: 0;
  width: 100%;
  background: rgba(10, 10, 10, 0.98);
  border-bottom: 1px solid var(--border-color);
  padding: 24px;
  z-index: 999;
}

.mobile-nav-drawer.active {
  display: block;
}

.mobile-nav-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.mobile-nav-links a {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-main);
  display: block;
  padding: 8px 0;
}

/* ==========================================================================
   Hero Banner Section
   ========================================================================== */
.hero-section {
  padding-top: 170px;
  padding-bottom: 100px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 18px;
  border-radius: 30px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #ffffff;
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 28px;
  animation: pulse 2.5s infinite;
}

@keyframes pulse {
  0%, 100% {
    box-shadow: 0 0 0 0 rgba(255, 255, 255, 0.25);
  }
  50% {
    box-shadow: 0 0 0 10px rgba(255, 255, 255, 0);
  }
}

.hero-title {
  font-size: 3.6rem;
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -1.5px;
  margin-bottom: 24px;
}

.text-gradient {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.2rem;
  color: var(--text-sub);
  max-width: 820px;
  margin: 0 auto 40px auto;
  line-height: 1.8;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 18px;
  flex-wrap: wrap;
  margin-bottom: 70px;
}

.metrics-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  max-width: 1060px;
  margin: 0 auto;
  padding: 30px;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow-card);
}

.metric-box {
  text-align: center;
  position: relative;
}

.metric-box:not(:last-child)::after {
  content: "";
  position: absolute;
  right: -12px;
  top: 15%;
  height: 70%;
  width: 1px;
  background: rgba(255, 255, 255, 0.08);
}

.metric-num {
  font-size: 2.3rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 4px;
  letter-spacing: -0.5px;
}

.metric-label {
  font-size: 0.85rem;
  color: var(--text-sub);
  font-weight: 500;
}

/* ==========================================================================
   Section Base & Header
   ========================================================================== */
.section-padding {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 60px auto;
}

.section-tag {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 2px;
  color: #a3a3a3;
  margin-bottom: 12px;
}

.section-title {
  font-size: 2.4rem;
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 1.05rem;
  color: var(--text-sub);
  line-height: 1.7;
}

/* ==========================================================================
   Node Ping Monitor
   ========================================================================== */
.ping-monitor-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 40px;
  box-shadow: var(--shadow-card);
}

.ping-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 30px;
}

.ping-item {
  background: #0d0d0d;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  padding: 18px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: all 0.25s ease;
}

.ping-item:hover {
  border-color: rgba(255, 255, 255, 0.4);
  transform: translateY(-2px);
  background: #171717;
}

.ping-info {
  display: flex;
  align-items: center;
  gap: 14px;
}

.ping-flag {
  font-size: 1.8rem;
}

.ping-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 2px;
}

.ping-detail {
  font-size: 0.78rem;
  color: var(--text-muted);
}

.ping-badge {
  text-align: right;
}

.ping-val {
  display: inline-block;
  font-family: monospace;
  font-size: 0.95rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 4px;
}

.ping-bar-bg {
  width: 65px;
  height: 4px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 2px;
  overflow: hidden;
}

.ping-bar-fill {
  height: 100%;
  background: #ffffff;
  border-radius: 2px;
}

/* ==========================================================================
   Bento Grid (Core Advantages)
   ========================================================================== */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.bento-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 36px;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  box-shadow: var(--shadow-card);
  position: relative;
  overflow: hidden;
}

.bento-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, #ffffff, transparent);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.bento-card:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 255, 255, 0.35);
  box-shadow: var(--shadow-glow);
}

.bento-card:hover::before {
  opacity: 1;
}

.bento-card.span-2 {
  grid-column: span 2;
}

.bento-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  color: #ffffff;
  margin-bottom: 22px;
}

.bento-card h3 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-main);
}

.bento-card p {
  font-size: 0.95rem;
  color: var(--text-sub);
  line-height: 1.7;
}

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

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 36px 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  position: relative;
  box-shadow: var(--shadow-card);
}

.pricing-card:hover {
  transform: translateY(-6px);
  border-color: #ffffff;
  box-shadow: 0 15px 35px -10px rgba(255, 255, 255, 0.15);
}

.pricing-card.popular {
  border-color: #ffffff;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.08) 0%, #121212 100%);
  transform: scale(1.03);
}

.popular-tag {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: #ffffff;
  color: #000000;
  font-size: 0.76rem;
  font-weight: 700;
  padding: 4px 14px;
  border-radius: 20px;
  box-shadow: 0 4px 12px rgba(255, 255, 255, 0.25);
  white-space: nowrap;
}

.plan-title {
  font-size: 1.4rem;
  font-weight: 800;
  margin-bottom: 6px;
}

.plan-subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 24px;
  min-height: 38px;
}

.plan-price-box {
  margin-bottom: 26px;
  padding-bottom: 20px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.plan-price {
  font-size: 2.4rem;
  font-weight: 800;
  color: #ffffff;
}

.plan-price span {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-sub);
}

.plan-features {
  list-style: none;
  margin-bottom: 32px;
}

.plan-features li {
  font-size: 0.88rem;
  color: var(--text-sub);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.plan-features li svg {
  width: 16px;
  height: 16px;
  color: #ffffff;
  flex-shrink: 0;
}

/* ==========================================================================
   Testimonials (用户评价)
   ========================================================================== */
.testimonials-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.testimonial-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 32px;
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.testimonial-stars {
  color: #ffffff;
  font-size: 1.1rem;
  margin-bottom: 16px;
}

.testimonial-text {
  font-size: 0.95rem;
  color: var(--text-sub);
  line-height: 1.75;
  margin-bottom: 24px;
}

.testimonial-user {
  display: flex;
  align-items: center;
  gap: 14px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: #222222;
  border: 1px solid rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
  color: #ffffff;
}

.user-name {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-main);
}

.user-role {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ==========================================================================
   FAQ Section (常见问题)
   ========================================================================== */
.faq-wrapper {
  max-width: 860px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  overflow: hidden;
  transition: all 0.25s ease;
}

.faq-item.active {
  border-color: #ffffff;
  box-shadow: 0 4px 20px rgba(255, 255, 255, 0.08);
}

.faq-question {
  padding: 22px 26px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-weight: 700;
  font-size: 1.05rem;
  user-select: none;
}

.faq-question:hover {
  color: #ffffff;
}

.faq-icon {
  font-size: 0.85rem;
  color: var(--text-muted);
  transition: transform 0.3s ease;
}

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

.faq-answer {
  display: none;
  padding: 0 26px 22px 26px;
  font-size: 0.95rem;
  color: var(--text-sub);
  line-height: 1.8;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}

.faq-item.active .faq-answer {
  display: block;
}

/* ==========================================================================
   Articles Grid (机场推荐与测评专栏)
   ========================================================================== */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 30px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-card);
}

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

.article-badge {
  font-size: 0.72rem;
  font-weight: 600;
  padding: 3px 10px;
  background: rgba(255, 255, 255, 0.08);
  color: #ffffff;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 6px;
  display: inline-block;
  margin-bottom: 14px;
}

.article-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 12px;
  line-height: 1.4;
}

.article-card h3 a {
  color: var(--text-main);
}

.article-card h3 a:hover {
  color: #a3a3a3;
}

.article-desc {
  font-size: 0.9rem;
  color: var(--text-sub);
  margin-bottom: 20px;
  line-height: 1.6;
}

.article-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-muted);
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding-top: 14px;
}

/* ==========================================================================
   Article Page Specific Layout
   ========================================================================== */
.article-page-header {
  padding-top: 140px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--border-color);
}

.article-body-content {
  max-width: 900px;
  margin: 50px auto;
  font-size: 1.08rem;
  line-height: 1.9;
  color: #d4d4d4;
}

.article-body-content h2 {
  font-size: 1.8rem;
  color: #ffffff;
  margin: 40px 0 20px 0;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border-color);
}

.article-body-content h3 {
  font-size: 1.35rem;
  color: #ffffff;
  margin: 30px 0 15px 0;
}

.article-body-content p {
  margin-bottom: 20px;
}

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

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

.article-cta-box {
  background: #0d0d0d;
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: var(--radius-lg);
  padding: 36px;
  text-align: center;
  margin: 50px 0;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.8);
}

.article-cta-box h3 {
  font-size: 1.5rem;
  color: #ffffff;
  margin-bottom: 12px;
}

.article-nav-links {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  margin-top: 50px;
  padding-top: 30px;
  border-top: 1px solid var(--border-color);
}

.article-nav-links a {
  background: #0d0d0d;
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #ffffff;
  padding: 10px 20px;
  border-radius: var(--radius-md);
  transition: all 0.25s ease;
}

.article-nav-links a:hover {
  background: #1c1c1c;
  border-color: #ffffff;
  color: #ffffff;
}

/* ==========================================================================
   Footer & PBN Precise Weight Transfer Pipeline (核心任务 2)
   ========================================================================== */
.site-footer {
  background: #050505;
  border-top: 1px solid var(--border-color);
  padding: 60px 0 30px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer-logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 16px;
}

.footer-desc {
  max-width: 600px;
  margin: 0 auto 24px auto;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.footer-copyright {
  margin-bottom: 20px;
  font-size: 0.84rem;
  color: var(--text-muted);
}

/* PBN Friendly Links Area (友情链接区) - 低调、美观、小字号、居中排版、纯 dofollow */
.pbn-links-area {
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px dashed rgba(255, 255, 255, 0.12);
  font-size: 0.82rem;
  color: #737373;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.pbn-links-title {
  color: #888888;
  font-weight: 500;
}

.pbn-link-item {
  color: #a3a3a3 !important;
  text-decoration: none;
  font-size: 0.82rem;
  transition: color 0.2s ease;
}

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

/* ==========================================================================
   Mobile Responsive Adjustments
   ========================================================================== */
@media (max-width: 1024px) {
  .hero-title {
    font-size: 2.8rem;
  }
  .metrics-row {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }
  .metric-box:not(:last-child)::after {
    display: none;
  }
  .ping-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .bento-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .testimonials-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-cta-btn {
    display: none;
  }
  .mobile-menu-toggle {
    display: block;
  }
  .hero-title {
    font-size: 2.2rem;
  }
  .hero-subtitle {
    font-size: 1.05rem;
  }
  .metrics-row {
    grid-template-columns: 1fr;
    padding: 20px;
  }
  .ping-grid {
    grid-template-columns: 1fr;
  }
  .bento-grid {
    grid-template-columns: 1fr;
  }
  .bento-card.span-2 {
    grid-column: span 1;
  }
  .pricing-grid {
    grid-template-columns: 1fr;
  }
  .testimonials-grid {
    grid-template-columns: 1fr;
  }
  .articles-grid {
    grid-template-columns: 1fr;
  }
  .article-nav-links {
    flex-direction: column;
  }
}