/* ==========================================================================
   阿达西 (Adaxi) - 全球专线网络加速器 Style Sheet
   Minimal Pure CSS - Fast Performance, Mobile-First Responsive
   Visual Palette: Dark Navy (#090d16), Electric Blue (#2563eb), Cyan (#06b6d4)
   ========================================================================== */

:root {
  --bg-base: #090d16;
  --bg-surface: #0f172a;
  --bg-card: #131e36;
  --bg-card-hover: #192745;
  
  --border-color: rgba(255, 255, 255, 0.08);
  --border-cyan: rgba(6, 182, 212, 0.3);
  --border-blue: rgba(37, 99, 235, 0.3);

  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-cyan: #06b6d4;
  --color-cyan-bright: #22d3ee;
  --color-success: #10b981;
  --color-warning: #f59e0b;

  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-subtle: #64748b;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Consolas, monospace;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --shadow-glow: 0 0 20px rgba(6, 182, 212, 0.15);
  --shadow-blue-glow: 0 0 25px rgba(37, 99, 235, 0.25);
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  background-color: var(--bg-base);
  color: var(--text-main);
  font-family: var(--font-sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a {
  color: var(--color-cyan-bright);
  text-decoration: none;
  transition: var(--transition);
}

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

ul, ol {
  list-style: none;
}

img, svg {
  vertical-align: middle;
  max-width: 100%;
}

/* --- Container & Layout --- */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 4.5rem 0;
  position: relative;
}

.section-alt {
  background-color: var(--bg-surface);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 760px;
  margin: 0 auto 3rem auto;
}

.section-title {
  font-size: clamp(1.75rem, 3.5vw, 2.25rem);
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* --- Badges & Buttons --- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.95rem;
  background: rgba(6, 182, 212, 0.1);
  border: 1px solid var(--border-cyan);
  border-radius: 50px;
  font-size: 0.85rem;
  color: var(--color-cyan-bright);
  font-weight: 600;
  margin-bottom: 1.25rem;
}

.badge-dot, .pulse-icon, .status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--color-success);
  box-shadow: 0 0 8px var(--color-success);
  display: inline-block;
  animation: pulse-dot 2s infinite;
  flex-shrink: 0;
}

@keyframes pulse-dot {
  0% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.4; transform: scale(0.85); }
  100% { opacity: 1; transform: scale(1); }
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0.75rem 1.6rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary) 0%, #1d4ed8 100%);
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.15);
  box-shadow: var(--shadow-blue-glow);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--color-primary-light) 0%, var(--color-primary) 100%);
  transform: translateY(-2px);
  box-shadow: 0 4px 25px rgba(37, 99, 235, 0.45);
  color: #ffffff;
}

.btn-secondary, .btn-outline {
  background: rgba(19, 30, 54, 0.6);
  color: var(--text-main);
  border: 1px solid var(--border-cyan);
}

.btn-secondary:hover, .btn-outline:hover {
  background: rgba(6, 182, 212, 0.15);
  border-color: var(--color-cyan-bright);
  color: var(--color-cyan-bright);
  transform: translateY(-2px);
}

.btn-large, .btn-lg {
  padding: 0.85rem 1.8rem;
  font-size: 1rem;
}

.btn-full, .btn-block {
  width: 100%;
}

/* --- Header & Nav --- */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(9, 13, 22, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  height: 72px;
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-main);
  letter-spacing: -0.01em;
}

.brand-logo svg {
  width: 28px;
  height: 28px;
  color: var(--color-cyan-bright);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.8rem;
}

.nav-link {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-muted);
}

.nav-link:hover, .nav-link.active {
  color: var(--color-cyan-bright);
}

/* --- Hero Section & Split Screen --- */
.hero, .hero-section {
  padding: 4.5rem 0 3.5rem 0;
  position: relative;
  overflow: hidden;
  background: radial-gradient(circle at 80% 20%, rgba(37, 99, 235, 0.14) 0%, transparent 50%),
              radial-gradient(circle at 20% 80%, rgba(6, 182, 212, 0.1) 0%, transparent 40%);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 3.5rem;
  align-items: center;
}

.hero-content {
  min-width: 0;
}

.hero-title {
  font-size: clamp(2.1rem, 4vw, 2.9rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: 1.25rem;
  color: var(--text-main);
  word-break: break-word;
}

.text-gradient {
  background: linear-gradient(135deg, #ffffff 0%, var(--color-cyan-bright) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle, .hero-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  line-height: 1.7;
  margin-bottom: 2rem;
  max-width: 600px;
}

.hero-buttons, .hero-actions {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  margin-bottom: 2.5rem;
  flex-wrap: wrap;
}

/* Hero Control Panel / Telemetry Card */
.hero-visual {
  min-width: 0;
}

.control-panel-card, .telemetry-card {
  background: var(--bg-card);
  border: 1px solid var(--border-cyan);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-glow);
  width: 100%;
}

.panel-header, .telemetry-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.82rem;
  font-family: var(--font-mono);
}

.panel-title, .telemetry-title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  color: var(--color-cyan-bright);
}

.panel-status {
  font-weight: 600;
  color: var(--color-success);
}

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

.node-item, .node-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: var(--transition);
}

.node-item:hover, .node-row:hover {
  border-color: var(--border-cyan);
  background: var(--bg-card-hover);
}

.node-info {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.node-flag {
  font-size: 1.2rem;
}

.node-name {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-main);
}

.node-meta, .node-ping {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

.node-ping {
  color: var(--color-cyan-bright);
  font-weight: 600;
}

.node-status {
  color: var(--color-success);
  font-size: 0.78rem;
  background: rgba(16, 185, 129, 0.1);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  border: 1px solid rgba(16, 185, 129, 0.2);
}

/* --- Core Advantages (3 Cards) --- */
.advantages-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.adv-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
}

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

.adv-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: rgba(6, 182, 212, 0.12);
  color: var(--color-cyan-bright);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.adv-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.75rem;
}

.adv-desc {
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* --- Streaming & AI Support Cards --- */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.platform-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem 1.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  transition: var(--transition);
}

.platform-card:hover {
  border-color: var(--border-cyan);
  background: var(--bg-card-hover);
  transform: translateY(-3px);
  box-shadow: var(--shadow-glow);
}

.platform-icon {
  font-size: 1.8rem;
  flex-shrink: 0;
}

.platform-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.2rem;
}

.platform-desc {
  font-size: 0.82rem;
  color: var(--text-muted);
}

/* --- Package Pricing Comparison Table --- */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  align-items: stretch;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: var(--transition);
}

.pricing-card.recommended {
  border: 2px solid var(--color-cyan-bright);
  box-shadow: 0 0 30px rgba(6, 182, 212, 0.25);
  background: linear-gradient(180deg, var(--bg-card) 0%, rgba(15, 23, 42, 0.9) 100%);
  transform: scale(1.03);
}

.popular-badge, .pricing-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background: linear-gradient(90deg, var(--color-cyan) 0%, var(--color-primary) 100%);
  color: #ffffff;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 0.3rem 1rem;
  border-radius: 50px;
  white-space: nowrap;
  box-shadow: 0 4px 12px rgba(6, 182, 212, 0.3);
}

.plan-header, .pricing-header {
  margin-bottom: 1.25rem;
}

.plan-title, .pricing-name {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.plan-subtitle, .pricing-sub {
  font-size: 0.88rem;
  color: var(--text-muted);
}

.plan-price, .pricing-amount-box {
  display: flex;
  align-items: baseline;
  gap: 0.25rem;
  margin-bottom: 1.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.price-currency, .pricing-currency {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-cyan-bright);
}

.price-val, .pricing-val {
  font-size: 2.75rem;
  font-weight: 800;
  font-family: var(--font-mono);
  color: var(--text-main);
  line-height: 1;
}

.price-period, .pricing-unit {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-left: 0.25rem;
}

.plan-features, .pricing-features {
  margin-bottom: 2rem;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.plan-features li, .pricing-features li {
  font-size: 0.9rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.plan-features li::before, .pricing-features li::before {
  content: "✓";
  color: var(--color-cyan-bright);
  font-weight: 700;
}

/* --- Articles Grid & Cards (图卡板块) --- */
.articles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition);
}

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

.article-tag {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-cyan-bright);
  background: rgba(6, 182, 212, 0.1);
  border: 1px solid var(--border-cyan);
  padding: 0.25rem 0.6rem;
  border-radius: 20px;
  margin-bottom: 0.75rem;
}

.article-card-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-main);
  line-height: 1.4;
  margin-bottom: 0.5rem;
}

.article-card-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.6;
  margin-bottom: 1.25rem;
}

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

.article-link {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-cyan-bright);
}

.article-link:hover {
  color: var(--text-main);
  text-decoration: underline;
}

/* --- Customer Reviews --- */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}

.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: var(--transition);
}

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

.review-header {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.user-avatar {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-cyan) 100%);
  color: #ffffff;
  font-weight: 700;
  font-size: 0.95rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.user-name {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-main);
}

.user-role {
  font-size: 0.82rem;
  color: var(--color-cyan-bright);
}

.review-text {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.7;
}

/* --- FAQ Accordion --- */
.faq-list {
  max-width: 840px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

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

.faq-item[open] {
  border-color: var(--border-cyan);
  box-shadow: var(--shadow-glow);
}

.faq-question {
  padding: 1.25rem 1.5rem;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-main);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  list-style: none;
}

.faq-question::-webkit-details-marker {
  display: none;
}

.faq-content {
  padding: 0 1.5rem 1.25rem 1.5rem;
  font-size: 0.95rem;
  color: var(--text-muted);
  line-height: 1.7;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  margin-top: 0.5rem;
  padding-top: 1rem;
}

/* --- Subpages Layout --- */
.subpage-header {
  padding: 4rem 0 2.5rem 0;
  background: radial-gradient(circle at 50% 0%, rgba(37, 99, 235, 0.15) 0%, transparent 60%);
  border-bottom: 1px solid var(--border-color);
  text-align: center;
}

.subpage-title {
  font-size: 2.25rem;
  font-weight: 800;
  margin-bottom: 0.75rem;
}

.subpage-desc {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto;
}

.subpage-content {
  padding: 4rem 0;
}

.content-box {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem;
  line-height: 1.8;
  color: var(--text-muted);
}

.content-box h2 {
  font-size: 1.4rem;
  color: var(--text-main);
  margin: 2rem 0 1rem 0;
}

.content-box h2:first-child {
  margin-top: 0;
}

.content-box p {
  margin-bottom: 1.25rem;
}

.content-box ul, .content-box ol {
  margin-bottom: 1.5rem;
  padding-left: 1.25rem;
}

.content-box li {
  margin-bottom: 0.5rem;
}

/* --- Footer (4 Links + Dofollow PBN Links) --- */
.footer {
  background: #05080e;
  border-top: 1px solid var(--border-color);
  padding: 3rem 0;
  text-align: center;
}

.footer-nav-four {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2.5rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.footer-nav-four a {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-main);
  transition: var(--transition);
}

.footer-nav-four a:hover {
  color: var(--color-cyan-bright);
}

.footer-copyright {
  font-size: 0.85rem;
  color: var(--text-subtle);
  border-top: 1px solid var(--border-color);
  padding-top: 1.5rem;
  max-width: 600px;
  margin: 0 auto;
}

/* --- Mobile Responsive Breakpoints --- */
@media (max-width: 1024px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  
  .advantages-grid, .articles-grid, .reviews-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .platform-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .pricing-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .pricing-card.recommended {
    transform: none;
  }
}

@media (max-width: 768px) {
  .hero-title {
    font-size: 2.1rem;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .nav-links {
    display: none;
  }

  .advantages-grid, .articles-grid, .reviews-grid, .platform-grid {
    grid-template-columns: 1fr;
  }

  .footer-nav-four {
    flex-direction: column;
    gap: 1.25rem;
  }
}