/* ==========================================================================
   Seafoam Publication Design System - Taishan Net (泰山云)
   Colors: White #FFFFFF, Deep Marine #24555D, Seafoam #B9DDD2, Soft Cream #F6F4EB
   ========================================================================== */

:root {
  --color-white: #FFFFFF;
  --color-deep-marine: #24555D;
  --color-deep-marine-dark: #193A40;
  --color-seafoam: #B9DDD2;
  --color-seafoam-light: #EBF5F2;
  --color-seafoam-hover: #A5D2C5;
  --color-soft-cream: #F6F4EB;
  --color-soft-cream-alt: #EFECE1;
  --color-text-main: #1C3337;
  --color-text-muted: #4A6367;
  --color-border: #D3E0DC;
  --color-border-light: #E4ECE9;

  --font-serif: "Songti SC", "Noto Serif SC", "SimSun", "STSong", "Source Han Serif SC", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;

  --container-max: 1200px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;

  --shadow-sm: 0 2px 8px rgba(36, 85, 93, 0.05);
  --shadow-md: 0 8px 24px rgba(36, 85, 93, 0.08);
  --shadow-lg: 0 16px 36px rgba(36, 85, 93, 0.12);

  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
}

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

html {
  font-size: 17px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.75;
  color: var(--color-text-main);
  background-color: var(--color-white);
  overflow-x: hidden;
}

/* Typography */
h1, h2, h3, h4, .font-serif {
  font-family: var(--font-serif);
  color: var(--color-deep-marine);
  font-weight: 700;
  line-height: 1.25;
}

h1 {
  font-size: 36px;
  letter-spacing: -0.01em;
}

@media (min-width: 992px) {
  h1 {
    font-size: 58px;
  }
}

h2 {
  font-size: 28px;
  margin-bottom: 0.75rem;
}

@media (min-width: 992px) {
  h2 {
    font-size: 36px;
  }
}

h3 {
  font-size: 22px;
  margin-bottom: 0.5rem;
}

p {
  margin-bottom: 1.25rem;
  color: var(--color-text-main);
}

p.lead {
  font-size: 19px;
  color: var(--color-text-muted);
  line-height: 1.6;
}

a {
  color: var(--color-deep-marine);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-deep-marine-dark);
}

.tabular-nums {
  font-variant-numeric: tabular-nums;
}

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

.section {
  padding: 4.5rem 0;
}

.section-alt {
  background-color: var(--color-soft-cream);
}

.section-header {
  margin-bottom: 3rem;
  text-align: center;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.section-tag {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-deep-marine);
  background-color: var(--color-seafoam);
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 1rem;
}

/* Buttons & CTAs */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 16px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  cursor: pointer;
  border: 2px solid transparent;
  text-align: center;
}

.btn-primary {
  background-color: var(--color-deep-marine);
  color: var(--color-white);
}

.btn-primary:hover {
  background-color: var(--color-deep-marine-dark);
  color: var(--color-white);
  box-shadow: var(--shadow-md);
}

.btn-secondary {
  background-color: var(--color-seafoam);
  color: var(--color-deep-marine);
  border-color: var(--color-seafoam);
}

.btn-secondary:hover {
  background-color: var(--color-seafoam-hover);
  border-color: var(--color-seafoam-hover);
  color: var(--color-deep-marine-dark);
}

.btn-outline {
  background-color: transparent;
  border-color: var(--color-deep-marine);
  color: var(--color-deep-marine);
}

.btn-outline:hover {
  background-color: var(--color-deep-marine);
  color: var(--color-white);
}

/* Header & Mobile Nav */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border-light);
  padding: 1rem 0;
}

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

.brand-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--color-deep-marine);
}

.brand-icon {
  width: 32px;
  height: 32px;
  background: var(--color-deep-marine);
  color: var(--color-seafoam);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-link {
  font-size: 16px;
  font-weight: 500;
  color: var(--color-text-main);
  padding: 6px 0;
  position: relative;
}

.nav-link:hover, .nav-link.active {
  color: var(--color-deep-marine);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-deep-marine);
  transition: width var(--transition-fast);
}

.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.mobile-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  color: var(--color-deep-marine);
}

@media (max-width: 991px) {
  .mobile-toggle {
    display: block;
  }

  .nav-menu {
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: var(--color-white);
    flex-direction: column;
    align-items: flex-start;
    padding: 1.5rem;
    gap: 1rem;
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    display: none;
  }

  .nav-menu.active {
    display: flex;
  }

  .nav-actions {
    display: none;
  }

  .nav-menu .nav-actions-mobile {
    display: flex;
    flex-direction: column;
    width: 100%;
    margin-top: 1rem;
    gap: 0.75rem;
  }
}

/* Hero Section */
.hero {
  padding: 4rem 0 5rem 0;
  background: linear-gradient(180deg, var(--color-white) 0%, var(--color-soft-cream) 100%);
  border-bottom: 1px solid var(--color-border);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 3rem;
  align-items: center;
}

@media (min-width: 992px) {
  .hero-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.hero-content h1 {
  margin-bottom: 1.5rem;
}

.hero-content p.lead {
  margin-bottom: 2rem;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2rem;
}

.hero-badges {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px dashed var(--color-border);
  font-size: 14px;
  color: var(--color-text-muted);
}

.hero-badge-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.hero-badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--color-deep-marine);
}

/* Hero SVG Dashboard */
.hero-dashboard {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-md);
  position: relative;
  overflow: hidden;
}

.dashboard-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-border-light);
  font-size: 14px;
  font-weight: 600;
  color: var(--color-deep-marine);
}

.dashboard-dots {
  display: flex;
  gap: 6px;
}

.dashboard-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.dashboard-dot.red { background-color: #E57373; }
.dashboard-dot.yellow { background-color: #FFB74D; }
.dashboard-dot.green { background-color: #81C784; }

.svg-chart-container {
  width: 100%;
  height: auto;
}

/* Navigation route animated stroke */
.route-animated {
  stroke-dasharray: 10 15;
  animation: routeDash 20s linear infinite;
}

@keyframes routeDash {
  from {
    stroke-dashoffset: 500;
  }
  to {
    stroke-dashoffset: 0;
  }
}

@media (prefers-reduced-motion: reduce) {
  .route-animated {
    animation: none !important;
  }
}

/* Three Benefits Section - Editorial Spreads */
.benefits-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 992px) {
  .benefits-grid {
    grid-template-columns: 1.2fr 0.8fr;
  }

  .benefit-card-featured {
    grid-row: span 2;
  }
}

.benefit-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2.5rem;
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  box-shadow: var(--shadow-sm);
}

.benefit-card-featured {
  background: linear-gradient(135deg, var(--color-soft-cream) 0%, var(--color-white) 100%);
  border-left: 6px solid var(--color-deep-marine);
}

.benefit-number {
  font-family: var(--font-serif);
  font-size: 3rem;
  font-weight: 700;
  color: var(--color-seafoam);
  line-height: 1;
  margin-bottom: 1rem;
}

.benefit-card-featured .benefit-number {
  color: var(--color-deep-marine);
  opacity: 0.25;
  font-size: 4.5rem;
}

.benefit-title {
  font-size: 24px;
  margin-bottom: 1rem;
}

.benefit-text {
  color: var(--color-text-muted);
  font-size: 16px;
  line-height: 1.7;
}

.editorial-tag {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-deep-marine);
  margin-bottom: 0.75rem;
}

/* Regional Nodes Section */
.nodes-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 576px) {
  .nodes-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 992px) {
  .nodes-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.node-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

.node-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.node-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-border-light);
}

.node-flag {
  font-size: 24px;
}

.node-region {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-deep-marine);
}

.node-meta-list {
  list-style: none;
  font-size: 14px;
  color: var(--color-text-muted);
}

.node-meta-list li {
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.node-meta-list li::before {
  content: "•";
  color: var(--color-deep-marine);
  font-weight: bold;
}

/* AI & Streaming Full Width Feature Areas */
.feature-banner {
  background-color: var(--color-deep-marine);
  color: var(--color-white);
  border-radius: var(--radius-lg);
  padding: 3.5rem 2.5rem;
  margin-bottom: 3rem;
  position: relative;
  overflow: hidden;
}

.feature-banner.streaming-banner {
  background-color: var(--color-soft-cream);
  color: var(--color-text-main);
  border: 1px solid var(--color-border);
}

.feature-banner h2 {
  color: var(--color-seafoam);
  margin-bottom: 1rem;
}

.feature-banner.streaming-banner h2 {
  color: var(--color-deep-marine);
}

.feature-banner p {
  color: var(--color-soft-cream);
  max-width: 800px;
  margin-bottom: 2rem;
  font-size: 18px;
}

.feature-banner.streaming-banner p {
  color: var(--color-text-muted);
}

.tech-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 1rem;
}

.tech-chip {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(185, 221, 210, 0.3);
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  text-align: center;
  font-weight: 600;
  font-size: 15px;
  color: var(--color-white);
  backdrop-filter: blur(4px);
}

.feature-banner.streaming-banner .tech-chip {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  color: var(--color-deep-marine);
}

/* Pricing Section */
.pricing-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  align-items: stretch;
}

@media (min-width: 768px) {
  .pricing-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1200px) {
  .pricing-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.pricing-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2.25rem 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  transition: transform var(--transition-normal);
}

.pricing-card:hover {
  transform: translateY(-4px);
}

.pricing-card.recommended {
  border: 2px solid var(--color-deep-marine);
  background-color: var(--color-soft-cream);
  box-shadow: var(--shadow-lg);
}

.recommended-badge {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--color-deep-marine);
  color: var(--color-seafoam);
  padding: 4px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.pricing-header {
  margin-bottom: 1.5rem;
  text-align: center;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border-light);
}

.pricing-title {
  font-size: 22px;
  margin-bottom: 0.5rem;
}

.pricing-price {
  font-family: var(--font-serif);
  font-size: 38px;
  font-weight: 700;
  color: var(--color-deep-marine);
  margin-bottom: 0.25rem;
}

.pricing-period {
  font-size: 14px;
  color: var(--color-text-muted);
}

.pricing-features {
  list-style: none;
  margin-bottom: 2rem;
  font-size: 15px;
}

.pricing-features li {
  margin-bottom: 0.75rem;
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--color-text-main);
}

.pricing-features li::before {
  content: "✓";
  color: var(--color-deep-marine);
  font-weight: bold;
}

.pricing-disclaimer {
  margin-top: 2.5rem;
  font-size: 13px;
  color: var(--color-text-muted);
  text-align: center;
  background-color: var(--color-soft-cream);
  padding: 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

/* Nine Article Cards Grid (3 Desktop / 2 Tablet / 1 Mobile) */
.articles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 768px) {
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .articles-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.article-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal);
}

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

.article-category {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-deep-marine);
  margin-bottom: 0.75rem;
}

.article-card h3 {
  font-size: 20px;
  line-height: 1.4;
  margin-bottom: 0.75rem;
}

.article-card h3 a {
  color: var(--color-deep-marine);
}

.article-card h3 a:hover {
  color: var(--color-deep-marine-dark);
}

.article-excerpt {
  font-size: 15px;
  color: var(--color-text-muted);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.article-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 13px;
  color: var(--color-text-muted);
  padding-top: 1rem;
  border-top: 1px solid var(--color-border-light);
}

.read-more-link {
  font-weight: 600;
  color: var(--color-deep-marine);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.read-more-link:hover {
  text-decoration: underline;
}

/* Testimonials Section */
.testimonials-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .testimonials-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.testimonial-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 1.75rem;
  position: relative;
}

.quote-icon {
  font-family: var(--font-serif);
  font-size: 3rem;
  color: var(--color-seafoam);
  line-height: 1;
  margin-bottom: -1rem;
}

.testimonial-text {
  font-size: 15px;
  font-style: italic;
  color: var(--color-text-main);
  margin-bottom: 1.25rem;
}

.testimonial-user {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-deep-marine);
}

.testimonial-label {
  font-size: 12px;
  color: var(--color-text-muted);
}

/* FAQ Accordion Section */
.faq-list {
  max-width: 840px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

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

.faq-item summary {
  padding: 1.25rem 1.5rem;
  font-family: var(--font-serif);
  font-size: 19px;
  font-weight: 700;
  color: var(--color-deep-marine);
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  user-select: none;
}

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

.faq-item summary::after {
  content: "+";
  font-size: 24px;
  font-family: var(--font-sans);
  color: var(--color-deep-marine);
  transition: transform var(--transition-fast);
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-answer {
  padding: 0 1.5rem 1.25rem 1.5rem;
  font-size: 16px;
  color: var(--color-text-main);
  line-height: 1.7;
  border-top: 1px solid var(--color-border-light);
}

/* Footer Section */
.footer {
  background-color: var(--color-deep-marine);
  color: var(--color-soft-cream);
  padding: 4rem 0 2rem 0;
  border-top: 1px solid var(--color-border);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  margin-bottom: 3rem;
}

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: 1.5fr repeat(3, 1fr);
  }
}

.footer-col h4 {
  color: var(--color-seafoam);
  font-size: 18px;
  margin-bottom: 1.25rem;
}

.footer-col p {
  color: #B2C9C5;
  font-size: 15px;
  line-height: 1.6;
}

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

.footer-links li {
  margin-bottom: 0.6rem;
}

.footer-links a {
  color: #DDEBE7;
  font-size: 15px;

}

.footer-links a:hover {
  color: var(--color-seafoam);
  text-decoration: underline;
}

.footer-bottom {
  padding-top: 2rem;
  border-top: 1px solid rgba(185, 221, 210, 0.2);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
  color: #A2BCB7;
}

@media (min-width: 768px) {
  .footer-bottom {
    flex-direction: row;
  }
}

/* Article Page Layout Styles */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-muted);
  margin-bottom: 2rem;
}

.breadcrumb a {
  color: var(--color-text-muted);
}

.breadcrumb a:hover {
  color: var(--color-deep-marine);
}

.breadcrumb-separator {
  color: var(--color-border);
}

.article-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

.article-header {
  margin-bottom: 2.5rem;
  border-bottom: 1px solid var(--color-border);
  padding-bottom: 2rem;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 14px;
  color: var(--color-text-muted);
  margin-top: 1rem;
}

.article-body {
  font-size: 17px;
  line-height: 1.85;
}

.article-body h2 {
  font-size: 28px;
  margin-top: 2.5rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--color-seafoam);
}

.article-body h3 {
  font-size: 22px;
  margin-top: 2rem;
  margin-bottom: 1rem;
}

.article-body ul, .article-body ol {
  margin-bottom: 1.5rem;
  padding-left: 1.5rem;
}

.article-body li {
  margin-bottom: 0.5rem;
}

.article-callout {
  background-color: var(--color-soft-cream);
  border-left: 4px solid var(--color-deep-marine);
  padding: 1.5rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 2rem 0;
  font-size: 16px;
}

.related-articles {
  margin-top: 4rem;
  padding-top: 3rem;
  border-top: 1px solid var(--color-border);
}