/* 
  狗狗云 (gougouvpn.mom) - Astrophysics Dark Field Theme CSS
  Theme: 宇宙暗物质与引力透镜风
*/

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=JetBrains+Mono:wght@400;500;700&display=swap');

:root {
  --bg-dark: #040406;
  --bg-card: rgba(14, 16, 24, 0.75);
  --bg-card-hover: rgba(22, 26, 38, 0.90);
  --border-color: rgba(200, 210, 224, 0.12);
  --border-glow: rgba(123, 97, 255, 0.35);
  
  --color-purple: #7B61FF;
  --color-purple-light: #A08CFF;
  --color-purple-glow: rgba(123, 97, 255, 0.25);
  --color-cyan: #00F0FF;
  --color-cyan-glow: rgba(0, 240, 255, 0.2);
  --color-silver: #C8D1E0;
  --color-muted: #8A99AD;
  --color-text: #F1F5F9;
  
  --font-main: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 24px;
  
  --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  scroll-behavior: smooth;
  font-family: var(--font-main);
  background-color: var(--bg-dark);
  color: var(--color-text);
  overflow-x: hidden;
}

body {
  background-color: var(--bg-dark);
  min-height: 100vh;
  position: relative;
  line-height: 1.6;
}

/* Background Canvas & Grid Overlay */
#canvas-lensing {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -2;
  pointer-events: none;
}

.astro-grid-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: 
    linear-gradient(rgba(123, 97, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(123, 97, 255, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
  z-index: -1;
  pointer-events: none;
}

/* Custom Cursor Trail */
.cursor-trail {
  position: fixed;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--color-cyan) 0%, var(--color-purple) 70%, transparent 100%);
  pointer-events: none;
  z-index: 9999;
  transform: translate(-50%, -50%);
  box-shadow: 0 0 12px var(--color-cyan), 0 0 25px var(--color-purple);
  transition: width 0.15s, height 0.15s;
}

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

/* Typography & Badges */
h1, h2, h3, h4 {
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #FFFFFF;
}

.gradient-text {
  background: linear-gradient(135deg, #FFFFFF 0%, var(--color-silver) 40%, var(--color-purple-light) 70%, var(--color-cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.astro-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  border-radius: 50px;
  background: rgba(123, 97, 255, 0.08);
  border: 1px solid var(--border-glow);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--color-cyan);
  margin-bottom: 20px;
  box-shadow: 0 0 20px rgba(123, 97, 255, 0.15);
}

.astro-badge .pulse-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--color-cyan);
  box-shadow: 0 0 10px var(--color-cyan);
  animation: pulse 1.8s infinite;
}

@keyframes pulse {
  0% { transform: scale(0.95); opacity: 0.8; }
  50% { transform: scale(1.3); opacity: 1; }
  100% { transform: scale(0.95); opacity: 0.8; }
}

/* Header & Navbar */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(4, 4, 6, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-color);
}

.nav-wrapper {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 80px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
}

.logo-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--color-purple) 0%, var(--color-cyan) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  box-shadow: 0 0 20px var(--color-purple-glow);
}

.logo-text {
  font-size: 1.35rem;
  font-weight: 800;
  color: #FFF;
  letter-spacing: -0.01em;
}

.logo-sub {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-cyan);
  display: block;
  margin-top: -4px;
}

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

.nav-links a {
  color: var(--color-silver);
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 500;
  transition: var(--transition);
}

.nav-links a:hover {
  color: var(--color-cyan);
  text-shadow: 0 0 10px var(--color-cyan-glow);
}

.nav-cta {
  display: flex;
  align-items: center;
  gap: 16px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 28px;
  border-radius: 50px;
  background: linear-gradient(135deg, var(--color-purple) 0%, #5B42F3 100%);
  color: #FFFFFF;
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 0 30px rgba(123, 97, 255, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
  transition: var(--transition);
  cursor: pointer;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 45px rgba(123, 97, 255, 0.6), 0 0 20px var(--color-cyan);
  color: #FFF;
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 28px;
  border-radius: 50px;
  background: rgba(255, 255, 255, 0.05);
  color: var(--color-silver);
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
  transition: var(--transition);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  color: #FFF;
  border-color: var(--color-purple);
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  color: #FFF;
  font-size: 24px;
  cursor: pointer;
}

/* Hero Section */
.hero-section {
  padding: 180px 0 100px;
  text-align: center;
  position: relative;
}

.hero-title {
  font-size: 3.8rem;
  line-height: 1.15;
  margin-bottom: 24px;
  max-width: 960px;
  margin-left: auto;
  margin-right: auto;
}

.hero-desc {
  font-size: 1.25rem;
  color: var(--color-muted);
  max-width: 720px;
  margin: 0 auto 40px;
  font-weight: 400;
}

.hero-cta-group {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 20px;
  margin-bottom: 60px;
}

/* Astrophysics Telemetry Dashboard Bar */
.astro-telemetry-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 24px 32px;
  backdrop-filter: blur(16px);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
  margin-top: 40px;
}

.telemetry-item {
  text-align: left;
  position: relative;
}

.telemetry-item:not(:last-child)::after {
  content: '';
  position: absolute;
  right: -10px;
  top: 15%;
  height: 70%;
  width: 1px;
  background: var(--border-color);
}

.telemetry-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.telemetry-val {
  font-family: var(--font-mono);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--color-cyan);
  text-shadow: 0 0 10px var(--color-cyan-glow);
}

.telemetry-sub {
  font-size: 0.8rem;
  color: var(--color-silver);
  margin-top: 2px;
}

/* Feature Cards Section */
.section-padding {
  padding: 100px 0;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-title {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.section-subtitle {
  color: var(--color-muted);
  font-size: 1.1rem;
  max-width: 640px;
  margin: 0 auto;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 36px 28px;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(12px);
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-purple), transparent);
  opacity: 0;
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-6px);
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  box-shadow: 0 20px 40px rgba(123, 97, 255, 0.15);
}

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

.feature-icon {
  width: 56px;
  height: 56px;
  border-radius: 12px;
  background: rgba(123, 97, 255, 0.1);
  border: 1px solid var(--border-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
  margin-bottom: 24px;
  color: var(--color-cyan);
}

.feature-card h3 {
  font-size: 1.3rem;
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--color-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

.coord-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: rgba(200, 210, 224, 0.4);
  margin-top: 20px;
  display: block;
}

/* Real-time Nodes Table */
.nodes-table-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 24px;
  backdrop-filter: blur(14px);
  overflow-x: auto;
}

.nodes-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
}

.nodes-table th {
  padding: 16px 20px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  text-transform: uppercase;
  color: var(--color-muted);
  border-bottom: 1px solid var(--border-color);
}

.nodes-table td {
  padding: 18px 20px;
  font-size: 0.95rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.nodes-table tr:hover td {
  background: rgba(123, 97, 255, 0.05);
}

.status-online {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: #10B981;
  font-weight: 600;
  font-size: 0.85rem;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #10B981;
  box-shadow: 0 0 8px #10B981;
}

/* Pricing Section */
.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-md);
  padding: 36px 24px;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
  backdrop-filter: blur(14px);
}

.pricing-card.featured {
  background: rgba(22, 24, 40, 0.85);
  border: 1px solid var(--color-purple);
  box-shadow: 0 0 40px rgba(123, 97, 255, 0.25);
  transform: translateY(-8px);
}

.featured-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(135deg, var(--color-purple), var(--color-cyan));
  color: #FFF;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 4px 16px;
  border-radius: 50px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  box-shadow: 0 0 15px var(--color-purple-glow);
}

.plan-name {
  font-size: 1.35rem;
  margin-bottom: 8px;
}

.plan-desc {
  font-size: 0.85rem;
  color: var(--color-muted);
  margin-bottom: 24px;
  min-height: 40px;
}

.plan-price {
  font-family: var(--font-mono);
  font-size: 2.5rem;
  font-weight: 800;
  color: #FFF;
  margin-bottom: 24px;
}

.plan-price span {
  font-size: 1rem;
  color: var(--color-muted);
  font-weight: 400;
}

.plan-features {
  list-style: none;
  margin-bottom: 32px;
  flex-grow: 1;
}

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

.plan-features li i {
  color: var(--color-cyan);
}

/* Articles Section Grid */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition);
  backdrop-filter: blur(12px);
}

.article-card:hover {
  transform: translateY(-5px);
  border-color: var(--color-purple);
  box-shadow: 0 15px 30px rgba(123, 97, 255, 0.15);
}

.article-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-cyan);
  background: rgba(0, 240, 255, 0.08);
  padding: 4px 12px;
  border-radius: 4px;
  margin-bottom: 14px;
}

.article-title {
  font-size: 1.15rem;
  line-height: 1.4;
  margin-bottom: 12px;
}

.article-title a {
  color: #FFF;
  text-decoration: none;
  transition: var(--transition);
}

.article-title a:hover {
  color: var(--color-purple-light);
}

.article-excerpt {
  color: var(--color-muted);
  font-size: 0.88rem;
  margin-bottom: 20px;
  line-height: 1.6;
}

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

.article-meta a {
  color: var(--color-cyan);
  text-decoration: none;
  font-weight: 600;
}

/* User Reviews (Testimonials) */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 28px;
  backdrop-filter: blur(12px);
}

.review-stars {
  color: #F59E0B;
  font-size: 1rem;
  margin-bottom: 14px;
}

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

.user-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-purple), var(--color-cyan));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #FFF;
}

.user-details h4 {
  font-size: 0.95rem;
}

.user-details span {
  font-size: 0.78rem;
  color: var(--color-muted);
}

/* FAQ Accordion */
.faq-list {
  max-width: 840px;
  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;
  backdrop-filter: blur(12px);
}

.faq-question {
  padding: 22px 28px;
  font-size: 1.1rem;
  font-weight: 600;
  color: #FFF;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
  transition: var(--transition);
}

.faq-question:hover {
  color: var(--color-cyan);
}

.faq-icon {
  font-size: 1.2rem;
  transition: transform 0.3s ease;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
  color: var(--color-cyan);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
  padding: 0 28px;
  color: var(--color-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.faq-item.active .faq-answer {
  max-height: 300px;
  padding: 0 28px 24px;
}

/* PBN & Footer Section (核心任务 2) */
.site-footer {
  background: #020204;
  border-top: 1px solid var(--border-color);
  padding: 60px 0 40px;
  margin-top: 80px;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 40px;
  margin-bottom: 40px;
}

.footer-brand p {
  color: var(--color-muted);
  font-size: 0.9rem;
  margin-top: 14px;
  max-width: 320px;
}

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

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

.footer-links li {
  margin-bottom: 10px;
}

.footer-links a {
  color: var(--color-silver);
  text-decoration: none;
  font-size: 0.88rem;
  transition: var(--transition);
}

.footer-links a:hover {
  color: var(--color-cyan);
}

/* PBN Friends Links Pipe Area (核心任务 2) */
.pbn-links-area {
  border-top: 1px dashed rgba(200, 210, 224, 0.15);
  padding-top: 24px;
  margin-top: 40px;
  text-align: center;
}

.pbn-title {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

.pbn-links-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px 24px;
  list-style: none;
  margin-bottom: 24px;
}

.pbn-links-list a {
  font-size: 0.82rem;
  color: rgba(200, 210, 224, 0.6);
  text-decoration: none;
  transition: var(--transition);
}

.pbn-links-list a:hover {
  color: var(--color-cyan);
  text-shadow: 0 0 8px var(--color-cyan-glow);
}

.copyright-text {
  font-size: 0.78rem;
  color: rgba(138, 153, 173, 0.5);
  font-family: var(--font-mono);
}

/* Article Template Styles */
.article-container {
  max-width: 860px;
  margin: 140px auto 80px;
  padding: 0 24px;
}

.article-header {
  margin-bottom: 40px;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 30px;
}

.article-body-content {
  color: #D1D5DB;
  font-size: 1.05rem;
  line-height: 1.85;
}

.article-body-content h2 {
  font-size: 1.65rem;
  margin: 40px 0 20px;
  color: #FFF;
  border-left: 4px solid var(--color-purple);
  padding-left: 14px;
}

.article-body-content h3 {
  font-size: 1.3rem;
  margin: 30px 0 16px;
  color: var(--color-silver);
}

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

.article-body-content ul, .article-body-content ol {
  margin-bottom: 24px;
  padding-left: 24px;
}

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

.article-cta-box {
  background: linear-gradient(135deg, rgba(123, 97, 255, 0.15) 0%, rgba(0, 240, 255, 0.08) 100%);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-md);
  padding: 32px;
  text-align: center;
  margin: 50px 0;
}

.article-cta-box h3 {
  font-size: 1.4rem;
  margin-bottom: 12px;
  color: #FFF;
}

.article-cta-box p {
  color: var(--color-silver);
  margin-bottom: 24px;
  font-size: 0.95rem;
}

/* Responsive Layout */
@media (max-width: 1024px) {
  .hero-title { font-size: 3rem; }
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .pricing-grid { grid-template-columns: repeat(2, 1fr); gap: 20px; }
  .articles-grid { grid-template-columns: repeat(2, 1fr); }
  .reviews-grid { grid-template-columns: repeat(1, 1fr); }
  .footer-top { grid-template-columns: 1fr 1fr; gap: 30px; }
  .astro-telemetry-bar { grid-template-columns: repeat(2, 1fr); gap: 16px; }
  .telemetry-item:not(:last-child)::after { display: none; }
}

@media (max-width: 768px) {
  .hero-title { font-size: 2.2rem; }
  .hero-desc { font-size: 1rem; }
  .features-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: 1fr; }
  .pricing-card.featured { transform: none; }
  .articles-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .mobile-toggle { display: block; }
  .nav-links.active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 80px;
    left: 0;
    width: 100%;
    background: #040406;
    border-bottom: 1px solid var(--border-color);
    padding: 24px;
    gap: 20px;
  }
  .footer-top { grid-template-columns: 1fr; }
  .astro-telemetry-bar { grid-template-columns: 1fr; }
  .hero-cta-group { flex-direction: column; width: 100%; }
  .hero-cta-group .btn-primary, .hero-cta-group .btn-secondary { width: 100%; }
}