/* ============================================================
   Chrome Download Site - Global Styles
   ============================================================ */

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: #1A1A1A;
  background-color: #FFFFFF;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: #4285F4;
  text-decoration: none;
  transition: opacity 0.2s ease;
}

a:hover {
  opacity: 0.8;
}

button {
  cursor: pointer;
  border: none;
  font-family: inherit;
}

/* --- Container --- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding-left: 24px;
  padding-right: 24px;
}

/* --- Typography --- */
.section-title {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.3;
  text-align: center;
  margin-bottom: 48px;
  color: #1A1A1A;
}

.section-subtitle {
  font-size: 16px;
  color: #6B7280;
  text-align: center;
  margin-top: -36px;
  margin-bottom: 48px;
}

/* --- Header / Navigation --- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: transparent;
  border-bottom: 1px solid transparent;
  transition: background-color 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.site-header.scrolled {
  background-color: #FFFFFF;
  border-bottom-color: #E5E7EB;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 32px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  font-size: 18px;
  color: #1A1A1A;
  text-decoration: none;
}

.logo:hover {
  opacity: 0.8;
}

.nav-tabs {
  display: flex;
  align-items: center;
  gap: 0;
  list-style: none;
}

.nav-tabs a {
  display: block;
  padding: 8px 16px;
  font-size: 14px;
  font-weight: 500;
  color: #6B7280;
  text-decoration: none;
  border-radius: 6px;
  transition: color 0.2s ease, background-color 0.2s ease;
}

.nav-tabs a:hover {
  color: #1A1A1A;
  background-color: #F3F4F6;
}

.nav-tabs a.active {
  color: #1A1A1A;
  font-weight: 600;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 24px;
  background-color: #4285F4;
  color: #FFFFFF;
  font-size: 14px;
  font-weight: 600;
  border-radius: 24px;
  text-decoration: none;
  transition: background-color 0.2s ease;
  border: none;
  cursor: pointer;
}

.header-cta:hover {
  background-color: #3367D6;
  opacity: 1;
}

/* Mobile menu toggle */
.mobile-toggle {
  display: none;
  background: none;
  border: none;
  padding: 8px;
  cursor: pointer;
}

/* --- Hero Section --- */
.hero-section {
  padding-top: 60px;
  padding-bottom: 80px;
  overflow: hidden;
}

.hero-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
}

.hero-content h1 {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.2;
  color: #1A1A1A;
  margin-bottom: 16px;
}

.hero-content .subtitle {
  font-size: 18px;
  color: #6B7280;
  line-height: 1.6;
  margin-bottom: 24px;
}

.hero-meta {
  list-style: none;
  margin-bottom: 32px;
}

.hero-meta li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: #6B7280;
  margin-bottom: 8px;
}

.hero-meta li svg {
  flex-shrink: 0;
  color: #34A853;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 16px 32px;
  background-color: #4285F4;
  color: #FFFFFF;
  font-size: 16px;
  font-weight: 600;
  border-radius: 24px;
  text-decoration: none;
  transition: background-color 0.2s ease;
  border: none;
  cursor: pointer;
}

.hero-cta:hover {
  background-color: #3367D6;
  opacity: 1;
}

.hero-image img {
  width: 100%;
  border-radius: 12px;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
}

/* Download message */
.download-msg {
  margin-top: 16px;
  font-size: 14px;
  color: #34A853;
  display: none;
  align-items: center;
  gap: 8px;
}

.download-msg.show {
  display: flex;
}

/* Warning banner */
.warning-banner {
  background-color: #FEF2F2;
  border: 1px solid #FECACA;
  border-radius: 8px;
  padding: 12px 20px;
  margin-bottom: 24px;
  display: none;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  color: #991B1B;
}

.warning-banner.show {
  display: flex;
}

/* --- Features Section --- */
.features-section {
  padding: 80px 0;
  background-color: #F9FAFB;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.feature-card {
  background-color: #FFFFFF;
  border-radius: 12px;
  padding: 32px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.1);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin-bottom: 20px;
  color: #4285F4;
}

.feature-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 12px;
  color: #1A1A1A;
}

.feature-card p {
  font-size: 14px;
  color: #6B7280;
  line-height: 1.6;
}

/* --- Requirements Section --- */
.requirements-section {
  padding: 80px 0;
  background-color: #FFFFFF;
}

.requirements-inner {
  max-width: 800px;
  margin: 0 auto;
}

.requirements-content {
  background-color: #F9FAFB;
  border-radius: 12px;
  padding: 40px;
}

.requirements-content h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 20px;
}

.requirements-list {
  list-style: none;
}

.requirements-list li {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  margin-bottom: 16px;
  font-size: 15px;
  color: #374151;
}

.requirements-list li svg {
  flex-shrink: 0;
  margin-top: 2px;
}

.requirements-note {
  margin-top: 20px;
  padding: 12px 16px;
  background-color: #FEF3C7;
  border-left: 4px solid #F59E0B;
  border-radius: 4px;
  font-size: 14px;
  color: #92400E;
}

/* --- Release Notes Section --- */
.release-section {
  padding: 80px 0;
  background-color: #F9FAFB;
}

.release-list {
  max-width: 800px;
  margin: 0 auto;
}

.release-item {
  background-color: #FFFFFF;
  border-radius: 12px;
  padding: 24px 32px;
  margin-bottom: 16px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
  border-left: 4px solid #4285F4;
}

.release-version {
  font-family: "SF Mono", "Fira Code", monospace;
  font-size: 16px;
  font-weight: 600;
  color: #4285F4;
  margin-bottom: 4px;
}

.release-date {
  font-size: 13px;
  color: #9CA3AF;
  margin-bottom: 8px;
}

.release-desc {
  font-size: 15px;
  color: #374151;
  line-height: 1.5;
}

/* --- FAQ Section --- */
.faq-section {
  padding: 80px 0;
  background-color: #FFFFFF;
}

.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid #E5E7EB;
}

.faq-question {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 0;
  background: none;
  border: none;
  font-size: 16px;
  font-weight: 500;
  color: #1A1A1A;
  cursor: pointer;
  text-align: left;
}

.faq-question:hover {
  color: #4285F4;
}

.faq-icon {
  flex-shrink: 0;
  width: 20px;
  height: 20px;
  color: #6B7280;
  transition: transform 0.2s ease;
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, opacity 0.3s ease;
  opacity: 0;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  opacity: 1;
}

.faq-answer-inner {
  padding-bottom: 20px;
  font-size: 15px;
  color: #6B7280;
  line-height: 1.6;
}

/* --- News Section (for news.html) --- */
.news-section {
  padding: 60px 0;
}

.news-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.news-card {
  background-color: #FFFFFF;
  border-radius: 12px;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.news-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.1);
}

.news-card-image {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.news-card-body {
  padding: 24px;
}

.news-card-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  font-size: 13px;
  color: #9CA3AF;
}

.news-card-title {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 10px;
  line-height: 1.4;
  color: #1A1A1A;
}

.news-card-excerpt {
  font-size: 14px;
  color: #6B7280;
  line-height: 1.6;
  margin-bottom: 16px;
}

.news-card-link {
  font-size: 14px;
  font-weight: 600;
  color: #4285F4;
}

/* --- Article Page Styles --- */
.article-section {
  padding: 40px 0 80px;
}

.article-header {
  margin-bottom: 40px;
}

.article-image {
  width: 100%;
  max-height: 400px;
  object-fit: cover;
  border-radius: 12px;
  margin-bottom: 32px;
}

.article-title {
  font-size: 36px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 16px;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 14px;
  color: #9CA3AF;
}

.article-meta span {
  display: flex;
  align-items: center;
  gap: 6px;
}

.article-body {
  max-width: 800px;
  margin: 0 auto;
}

.article-body h2 {
  font-size: 24px;
  font-weight: 600;
  margin: 40px 0 16px;
  color: #1A1A1A;
}

.article-body h3 {
  font-size: 20px;
  font-weight: 600;
  margin: 32px 0 12px;
  color: #1A1A1A;
}

.article-body p {
  font-size: 16px;
  color: #374151;
  line-height: 1.8;
  margin-bottom: 16px;
}

.article-body ul,
.article-body ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.article-body li {
  font-size: 16px;
  color: #374151;
  line-height: 1.8;
  margin-bottom: 8px;
}

.article-back {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 40px;
  font-size: 14px;
  font-weight: 500;
  color: #6B7280;
  text-decoration: none;
}

.article-back:hover {
  color: #4285F4;
}

/* --- Download Page Specific --- */
.platform-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 60px;
}

.platform-card {
  background-color: #FFFFFF;
  border: 1px solid #E5E7EB;
  border-radius: 12px;
  padding: 32px;
  text-align: center;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.platform-card:hover {
  border-color: #4285F4;
  box-shadow: 0 4px 20px rgba(66, 133, 244, 0.1);
}

.platform-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 16px;
  color: #4285F4;
}

.platform-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.platform-version {
  font-family: "SF Mono", "Fira Code", monospace;
  font-size: 13px;
  color: #9CA3AF;
  margin-bottom: 12px;
}

.platform-req {
  font-size: 13px;
  color: #6B7280;
  margin-bottom: 20px;
}

.platform-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background-color: #4285F4;
  color: #FFFFFF;
  font-size: 14px;
  font-weight: 600;
  border-radius: 24px;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s ease;
}

.platform-btn:hover {
  background-color: #3367D6;
}

/* --- zh-cn Page Specific --- */
.tutorial-nav {
  position: sticky;
  top: 80px;
  background-color: #F9FAFB;
  border-radius: 12px;
  padding: 24px;
}

.tutorial-nav h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 16px;
}

.tutorial-nav ul {
  list-style: none;
}

.tutorial-nav li {
  margin-bottom: 8px;
}

.tutorial-nav a {
  font-size: 14px;
  color: #6B7280;
  text-decoration: none;
  display: block;
  padding: 6px 0;
  transition: color 0.2s ease;
}

.tutorial-nav a:hover {
  color: #4285F4;
}

.tutorial-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 40px;
}

.shortcut-table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
}

.shortcut-table th,
.shortcut-table td {
  padding: 12px 16px;
  text-align: left;
  border-bottom: 1px solid #E5E7EB;
}

.shortcut-table th {
  font-weight: 600;
  font-size: 14px;
  color: #1A1A1A;
  background-color: #F9FAFB;
}

.shortcut-table td {
  font-size: 14px;
  color: #374151;
}

.shortcut-table code {
  font-family: "SF Mono", "Fira Code", monospace;
  font-size: 13px;
  background-color: #F3F4F6;
  padding: 2px 8px;
  border-radius: 4px;
  color: #4285F4;
}

.extension-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.extension-card {
  background-color: #F9FAFB;
  border-radius: 8px;
  padding: 20px;
}

.extension-card h4 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
}

.extension-card p {
  font-size: 13px;
  color: #6B7280;
  line-height: 1.5;
}

/* --- Footer --- */
.site-footer {
  background-color: #1F2937;
  color: #9CA3AF;
  padding: 60px 0 32px;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 40px;
  margin-bottom: 40px;
}

.footer-col h4 {
  font-size: 14px;
  font-weight: 600;
  color: #F3F4F6;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.footer-col ul {
  list-style: none;
}

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

.footer-col a {
  font-size: 14px;
  color: #9CA3AF;
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-col a:hover {
  color: #FFFFFF;
  opacity: 1;
}

.footer-bottom {
  border-top: 1px solid #374151;
  padding-top: 24px;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: #6B7280;
  margin-bottom: 4px;
}

/* --- Utility Classes --- */
.text-center { text-align: center; }
.mt-20 { margin-top: 20px; }
.mb-20 { margin-bottom: 20px; }

/* --- Scroll Reveal Animations --- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }
.reveal-delay-5 { transition-delay: 0.5s; }
.reveal-delay-6 { transition-delay: 0.6s; }

/* --- Spin Animation for Loading --- */
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.spinner {
  animation: spin 1s linear infinite;
}

/* --- Responsive --- */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .news-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .platform-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .tutorial-layout {
    grid-template-columns: 200px 1fr;
  }
}

@media (max-width: 768px) {
  .hero-inner {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-content h1 {
    font-size: 32px;
  }
  .hero-image {
    order: -1;
  }
  .features-grid {
    grid-template-columns: 1fr;
  }
  .news-grid {
    grid-template-columns: 1fr;
  }
  .footer-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .nav-tabs {
    display: none;
  }
  .mobile-toggle {
    display: block;
  }
  .platform-grid {
    grid-template-columns: 1fr;
  }
  .tutorial-layout {
    grid-template-columns: 1fr;
  }
  .tutorial-nav {
    position: static;
    margin-bottom: 32px;
  }
  .extension-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .hero-content h1 {
    font-size: 28px;
  }
  .section-title {
    font-size: 24px;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .requirements-content {
    padding: 24px;
  }
}