/* ==========================================================================
   鲲鹏加速 (Kunpeng Acceleration) - Pure Native CSS Stylesheet
   Modern High-Tech Aesthetic | Zero Bloat | Second-Level Instant Load
   ========================================================================== */

:root {
  --bg-primary: #0a0d14;
  --bg-secondary: #111726;
  --bg-card: rgba(20, 28, 45, 0.75);
  --bg-card-hover: rgba(28, 38, 62, 0.9);
  --border-color: rgba(56, 189, 248, 0.15);
  --border-glow: rgba(56, 189, 248, 0.4);
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  
  --accent-cyan: #38bdf8;
  --accent-blue: #3b82f6;
  --accent-indigo: #6366f1;
  --accent-gradient: linear-gradient(135deg, #38bdf8 0%, #3b82f6 50%, #818cf8 100%);
  --accent-gradient-glow: radial-gradient(circle at center, rgba(56, 189, 248, 0.15) 0%, transparent 70%);
  
  --success: #10b981;
  --warning: #f59e0b;
  
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --container-max: 1200px;
  --header-height: 72px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 24px rgba(56, 189, 248, 0.2);
  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Accessibility: Prefers reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

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

html {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background-image: 
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(56, 189, 248, 0.12), transparent 70%),
    radial-gradient(ellipse 60% 40% at 80% 60%, rgba(99, 102, 241, 0.08), transparent 70%);
  background-attachment: fixed;
}

/* Keyboard accessibility: Skip link */
.skip-link {
  position: absolute;
  top: -100px;
  left: 1rem;
  background: var(--accent-cyan);
  color: #04101e;
  padding: 0.75rem 1.25rem;
  font-weight: 700;
  z-index: 10000;
  border-radius: var(--radius-sm);
  transition: top 0.2s;
  text-decoration: none;
}
.skip-link:focus {
  top: 1rem;
  outline: 3px solid #ffffff;
}

/* Fixed Header clearance for anchors */
[id] {
  scroll-margin-top: calc(var(--header-height) + 1.5rem);
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: var(--transition);
}
a:hover {
  color: #7dd3fc;
  text-decoration: underline;
}
a:focus-visible, button:focus-visible, summary:focus-visible {
  outline: 2px solid var(--accent-cyan);
  outline-offset: 3px;
}

img, svg {
  display: block;
  max-width: 100%;
}

/* Layout Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: rgba(10, 13, 20, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  height: var(--header-height);
  display: flex;
  align-items: center;
}

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

.logo-group {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-primary);
}
.logo-group:hover {
  text-decoration: none;
}
.logo-icon {
  width: 36px;
  height: 36px;
  background: var(--accent-gradient);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #04101e;
  box-shadow: 0 0 12px rgba(56, 189, 248, 0.4);
}
.logo-text {
  font-size: 1.25rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.logo-badge {
  font-size: 0.7rem;
  padding: 0.15rem 0.45rem;
  background: rgba(56, 189, 248, 0.15);
  border: 1px solid rgba(56, 189, 248, 0.3);
  color: var(--accent-cyan);
  border-radius: var(--radius-full);
  font-weight: 600;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  list-style: none;
}
.nav-link {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  padding: 0.5rem 0.25rem;
  position: relative;
}
.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
  text-decoration: none;
}
.nav-link.active::after, .nav-link:hover::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--accent-cyan);
  border-radius: 2px;
}

.header-cta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

/* Button & CTA System */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  min-height: 44px;
  min-width: 44px;
  padding: 0.65rem 1.4rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  text-decoration: none;
  border: 1px solid transparent;
  white-space: nowrap;
}
.btn:hover {
  text-decoration: none;
  transform: translateY(-2px);
}
.btn-primary {
  background: var(--accent-gradient);
  color: #04101e;
  border-color: rgba(56, 189, 248, 0.4);
  box-shadow: 0 4px 16px rgba(56, 189, 248, 0.25);
}
.btn-primary:hover {
  color: #020813;
  box-shadow: 0 6px 22px rgba(56, 189, 248, 0.4);
}
.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-primary);
  border-color: var(--border-color);
}
.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--accent-cyan);
  color: var(--text-primary);
}
.btn-lg {
  padding: 0.85rem 1.85rem;
  font-size: 1.05rem;
  min-height: 48px;
}
.btn-block {
  width: 100%;
}

/* Hero Section */
.hero-section {
  padding: 5rem 0 3.5rem;
  position: relative;
  text-align: center;
}
.hero-badge-wrap {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.85rem;
  background: rgba(56, 189, 248, 0.08);
  border: 1px solid rgba(56, 189, 248, 0.25);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  color: var(--accent-cyan);
  margin-bottom: 1.5rem;
  font-weight: 500;
}
.hero-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1.25rem;
  letter-spacing: -0.03em;
}
.text-gradient {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-desc {
  max-width: 760px;
  margin: 0 auto 2rem;
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}
.hero-trust {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  color: var(--text-muted);
  font-size: 0.9rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}
.trust-item {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
}
.trust-item svg {
  color: var(--success);
}

/* Section Common Styling */
.section-block {
  padding: 4.5rem 0;
  position: relative;
}
.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 3rem;
}
.section-tag {
  color: var(--accent-cyan);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
}
.section-title {
  font-size: clamp(1.65rem, 3.5vw, 2.35rem);
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 0.75rem;
}
.section-subtitle {
  color: var(--text-secondary);
  font-size: 1rem;
}

/* Cards & Grid Systems */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.75rem;
}
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.75rem;
}
.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.75rem;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}
.feature-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent-gradient);
  opacity: 0;
  transition: var(--transition);
}
.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  transform: translateY(-4px);
  box-shadow: var(--shadow-glow);
}
.feature-card:hover::before {
  opacity: 1;
}

.card-icon {
  width: 52px;
  height: 52px;
  border-radius: var(--radius-md);
  background: rgba(56, 189, 248, 0.12);
  border: 1px solid rgba(56, 189, 248, 0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-cyan);
  margin-bottom: 1.5rem;
}
.feature-title {
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}
.feature-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.65;
}

/* Streaming & AI Cards */
.media-ai-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  transition: var(--transition);
}
.media-ai-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-3px);
}
.media-ai-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.badge-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 1rem;
}
.pill-badge {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.1);
  padding: 0.3rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* Pricing Table Section */
.pricing-wrapper {
  overflow-x: auto;
  margin-top: 1.5rem;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  background: var(--bg-card);
}
.pricing-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 680px;
  text-align: left;
}
.pricing-table caption {
  padding: 1rem;
  text-align: left;
  font-size: 0.9rem;
  color: var(--text-muted);
  border-bottom: 1px solid var(--border-color);
}
.pricing-table th, .pricing-table td {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.pricing-table th {
  background: rgba(17, 23, 38, 0.8);
  font-weight: 700;
  color: var(--text-primary);
  font-size: 0.95rem;
}
.pricing-table tr:hover td {
  background: rgba(56, 189, 248, 0.03);
}
.pricing-table .plan-name {
  font-weight: 700;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.pricing-table .plan-price {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--accent-cyan);
}
.pricing-table .plan-price small {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
}
.badge-hot {
  font-size: 0.7rem;
  padding: 0.15rem 0.5rem;
  background: rgba(245, 158, 11, 0.15);
  border: 1px solid rgba(245, 158, 11, 0.3);
  color: var(--warning);
  border-radius: var(--radius-full);
  font-weight: 700;
}

/* Reviews Section */
.review-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.review-stars {
  color: #fbbf24;
  margin-bottom: 0.85rem;
  display: flex;
  gap: 0.2rem;
}
.review-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.25rem;
}
.review-author {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}
.author-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: var(--accent-cyan);
  font-size: 0.9rem;
}
.author-name {
  font-weight: 700;
  font-size: 0.95rem;
}
.author-meta {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* FAQ Accordion (Always Open / Details & Summary Native) */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-width: 860px;
  margin: 0 auto;
}
.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: var(--transition);
}
.faq-item:hover {
  border-color: var(--border-glow);
}
.faq-item summary {
  padding: 1.25rem 1.5rem;
  font-size: 1.05rem;
  font-weight: 700;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
  color: var(--text-primary);
}
.faq-item summary::-webkit-details-marker {
  display: none;
}
.faq-item summary::after {
  content: "▾";
  font-size: 1.25rem;
  color: var(--accent-cyan);
  transition: transform 0.2s ease;
}
.faq-item[open] summary::after {
  transform: rotate(180deg);
}
.faq-content {
  padding: 0 1.5rem 1.25rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
  padding-top: 1rem;
}
.faq-content a {
  text-decoration: underline;
}

/* Breadcrumb Navigation */
.breadcrumb-nav {
  padding: 1rem 0;
  font-size: 0.85rem;
  color: var(--text-muted);
}
.breadcrumb-nav ol {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  list-style: none;
  flex-wrap: wrap;
}
.breadcrumb-nav li:not(:last-child)::after {
  content: "/";
  margin-left: 0.5rem;
  color: var(--text-muted);
}
.breadcrumb-nav a {
  color: var(--text-secondary);
}
.breadcrumb-nav a:hover {
  color: var(--accent-cyan);
}

/* Article & Content Body */
.article-container {
  max-width: 840px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}
.article-header {
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 1.5rem;
}
.article-title {
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 800;
  line-height: 1.3;
  margin-bottom: 1rem;
}
.article-meta {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  color: var(--text-muted);
  font-size: 0.88rem;
  flex-wrap: wrap;
}
.article-body {
  font-size: 1.05rem;
  line-height: 1.8;
  color: #cbd5e1;
}
.article-body h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 2.25rem 0 1rem;
  color: var(--text-primary);
  border-left: 4px solid var(--accent-cyan);
  padding-left: 0.75rem;
}
.article-body h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 1.75rem 0 0.75rem;
  color: var(--text-primary);
}
.article-body p {
  margin-bottom: 1.25rem;
}
.article-body ul, .article-body ol {
  margin: 1rem 0 1.5rem 1.5rem;
}
.article-body li {
  margin-bottom: 0.5rem;
}
.article-body blockquote {
  border-left: 4px solid var(--accent-blue);
  background: rgba(59, 130, 246, 0.08);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--text-secondary);
}
.article-cta-box {
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.1), rgba(59, 130, 246, 0.15));
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 2rem;
  margin: 3rem 0;
  text-align: center;
}
.article-cta-box h3 {
  font-size: 1.4rem;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}
.article-cta-box p {
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 1.5rem;
}

/* Article List / Knowledge Directory */
.article-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.75rem;
  margin: 2.5rem 0;
}
.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition);
}
.article-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  transform: translateY(-3px);
}
.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}
.article-card-title a {
  color: var(--text-primary);
}
.article-card-title a:hover {
  color: var(--accent-cyan);
}
.article-card-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex-grow: 1;
}
.article-card-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, 0.05);
  padding-top: 0.85rem;
}

/* Static Content Pages (About, Terms, Privacy, Sitemap) */
.legal-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  margin: 2rem 0 4rem;
}
.legal-card h2 {
  font-size: 1.4rem;
  font-weight: 700;
  margin: 2rem 0 1rem;
  color: var(--text-primary);
  border-left: 3px solid var(--accent-cyan);
  padding-left: 0.75rem;
}
.legal-card h2:first-of-type {
  margin-top: 0;
}
.legal-card p {
  color: var(--text-secondary);
  margin-bottom: 1.25rem;
  line-height: 1.75;
}
.legal-card ul {
  margin: 1rem 0 1.5rem 1.5rem;
  color: var(--text-secondary);
}
.legal-card li {
  margin-bottom: 0.5rem;
}

.sitemap-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
  margin-top: 1.5rem;
}
.sitemap-group {
  background: rgba(17, 23, 38, 0.6);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.5rem;
}
.sitemap-group h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: var(--accent-cyan);
}
.sitemap-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.sitemap-links a {
  color: var(--text-secondary);
  font-size: 0.95rem;
}
.sitemap-links a:hover {
  color: var(--accent-cyan);
  padding-left: 4px;
}

/* Footer Section - STRICT REQUIREMENT: Only 4 Titles in footer */
.site-footer {
  margin-top: auto;
  background: #06090e;
  border-top: 1px solid var(--border-color);
  padding: 3rem 0 2rem;
  font-size: 0.9rem;
}
.footer-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 2.5rem;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  list-style: none;
}
.footer-link {
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 1rem;
  padding: 0.5rem;
  transition: var(--transition);
}
.footer-link:hover {
  color: var(--accent-cyan);
  text-decoration: none;
}
.footer-bottom {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  padding-top: 1.5rem;
}

/* Responsive Media Queries */
@media (max-width: 1024px) {
  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }
  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  :root {
    --header-height: 64px;
  }
  .grid-3, .grid-2, .grid-4, .article-list, .sitemap-grid {
    grid-template-columns: 1fr;
  }
  .nav-menu {
    display: none; /* Mobile simplified header to avoid complex JS menu */
  }
  .hero-section {
    padding: 3rem 0 2rem;
  }
  .hero-actions {
    flex-direction: column;
    width: 100%;
  }
  .hero-actions .btn {
    width: 100%;
  }
  .footer-nav {
    flex-direction: column;
    gap: 1rem;
  }
  .pricing-table th, .pricing-table td {
    padding: 1rem 0.75rem;
  }
  .article-title {
    font-size: 1.65rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding-left: 1rem;
    padding-right: 1rem;
  }
  .hero-trust {
    flex-direction: column;
    gap: 0.75rem;
  }
}