/* ============================================
   Chrome Browser Landing Page - Global Styles
   ============================================ */

/* CSS Variables */
:root {
  --primary: #1a73e8;
  --primary-dark: #1557b0;
  --primary-light: #e8f0fe;
  --secondary: #34a853;
  --accent: #fbbc04;
  --danger: #ea4335;
  --text-primary: #202124;
  --text-secondary: #5f6368;
  --text-muted: #80868b;
  --bg-white: #ffffff;
  --bg-light: #f8f9fa;
  --bg-gray: #f1f3f4;
  --border: #dadce0;
  --shadow-sm: 0 1px 2px 0 rgba(60, 64, 67, 0.08);
  --shadow-md: 0 2px 8px 0 rgba(60, 64, 67, 0.12);
  --shadow-lg: 0 4px 16px 0 rgba(60, 64, 67, 0.16);
  --shadow-xl: 0 8px 32px 0 rgba(60, 64, 67, 0.24);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
  --nav-height: 72px;
}

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

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text-primary);
  line-height: 1.6;
  background: var(--bg-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  text-decoration: none;
  color: inherit;
}

ul, ol {
  list-style: none;
}

/* Spin Animation for Loader */
@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* Fade In Animation */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.animate-fadeInUp {
  animation: fadeInUp 0.6s ease-out forwards;
}

.animate-fadeIn {
  animation: fadeIn 0.5s ease-out forwards;
}

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

/* ============================================
   Navigation
   ============================================ */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  transition: var(--transition);
}

.navbar-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
}

.nav-brand svg {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: var(--transition);
  position: relative;
}

.nav-link:hover {
  color: var(--primary);
  background: var(--primary-light);
}

.nav-link.active {
  color: var(--primary);
  background: var(--primary-light);
  font-weight: 600;
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 20px;
  right: 20px;
  height: 2px;
  background: var(--primary);
  border-radius: 1px;
}

.nav-cta {
  padding: 10px 22px;
  background: var(--primary);
  color: #fff;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  transition: var(--transition);
  border: none;
  cursor: pointer;
}

.nav-cta:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Mobile Menu Toggle */
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
  cursor: pointer;
  background: none;
  border: none;
}

.mobile-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 1px;
  transition: var(--transition);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: var(--radius-md);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  border: none;
  outline: none;
  position: relative;
  overflow: hidden;
}

.btn:disabled {
  opacity: 0.7;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover:not(:disabled) {
  background: var(--primary-dark);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: var(--bg-white);
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--primary-light);
  transform: translateY(-2px);
}

.btn-large {
  padding: 16px 40px;
  font-size: 1.1rem;
  border-radius: var(--radius-lg);
}

.btn-sm {
  padding: 10px 20px;
  font-size: 0.875rem;
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
  padding: calc(var(--nav-height) + 80px) 0 100px;
  background: linear-gradient(135deg, var(--bg-light) 0%, #e8f0fe 50%, var(--bg-light) 100%);
  position: relative;
  overflow: hidden;
}

.hero-bg-pattern {
  position: absolute;
  inset: 0;
  opacity: 0.4;
  background-image: radial-gradient(circle at 1px 1px, var(--primary) 1px, transparent 0);
  background-size: 40px 40px;
}

.hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-content {
  animation: fadeInUp 0.8s ease-out;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  background: rgba(26, 115, 232, 0.1);
  color: var(--primary);
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 24px;
}

.hero-title {
  font-size: 3.2rem;
  font-weight: 800;
  line-height: 1.15;
  color: var(--text-primary);
  margin-bottom: 20px;
  letter-spacing: -0.02em;
}

.hero-title span {
  color: var(--primary);
}

.hero-desc {
  font-size: 1.15rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 36px;
  max-width: 520px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-meta {
  display: flex;
  align-items: center;
  gap: 24px;
  margin-top: 32px;
  font-size: 0.875rem;
  color: var(--text-muted);
}

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

.hero-visual {
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  animation: float 6s ease-in-out infinite;
}

.hero-visual-bg {
  position: absolute;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(26, 115, 232, 0.12) 0%, transparent 70%);
  border-radius: 50%;
}

.hero-visual img,
.hero-visual svg {
  position: relative;
  z-index: 1;
}

/* ============================================
   Section Styles
   ============================================ */
.section {
  padding: 80px 0;
}

.section-alt {
  background: var(--bg-light);
}

.section-header {
  text-align: center;
  max-width: 700px;
  margin: 0 auto 60px;
}

.section-label {
  display: inline-block;
  padding: 6px 16px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: 100px;
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.section-title {
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 16px;
  line-height: 1.2;
}

.section-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ============================================
   Feature Cards
   ============================================ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.feature-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px;
  transition: var(--transition);
  border: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  opacity: 0;
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: transparent;
}

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

.feature-icon {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: var(--primary-light);
  color: var(--primary);
  margin-bottom: 20px;
}

.feature-icon svg {
  width: 28px;
  height: 28px;
}

.feature-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.feature-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

/* ============================================
   Platform Cards
   ============================================ */
.platforms-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.platform-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 28px;
  text-align: center;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.platform-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}

.platform-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: var(--bg-gray);
}

.platform-icon svg {
  width: 36px;
  height: 36px;
}

.platform-name {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.platform-version {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.platform-desc {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 16px;
}

.platform-btn {
  width: 100%;
}

/* ============================================
   Detail Sections
   ============================================ */
.detail-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 80px;
}

.detail-block:last-child {
  margin-bottom: 0;
}

.detail-block.reverse {
  direction: rtl;
}

.detail-block.reverse > * {
  direction: ltr;
}

.detail-visual {
  background: var(--bg-gray);
  border-radius: var(--radius-lg);
  padding: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 300px;
}

.detail-content h3 {
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.detail-content p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.detail-list {
  margin-top: 20px;
}

.detail-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 8px 0;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.detail-list li svg {
  width: 20px;
  height: 20px;
  color: var(--secondary);
  flex-shrink: 0;
  margin-top: 2px;
}

/* ============================================
   Reviews
   ============================================ */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.review-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 28px;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.review-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.review-stars {
  display: flex;
  gap: 4px;
  margin-bottom: 16px;
}

.review-stars svg {
  width: 18px;
  height: 18px;
  color: var(--accent);
}

.review-text {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.review-author {
  display: flex;
  align-items: center;
  gap: 12px;
}

.review-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 700;
  font-size: 0.9rem;
}

.review-name {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-primary);
}

.review-role {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ============================================
   Stats
   ============================================ */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.stat-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px 24px;
  text-align: center;
  border: 1px solid var(--border);
  transition: var(--transition);
}

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

.stat-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: var(--primary-light);
  color: var(--primary);
}

.stat-icon svg {
  width: 24px;
  height: 24px;
}

.stat-number {
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 4px;
  line-height: 1;
}

.stat-label {
  font-size: 0.9rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* ============================================
   Comparison Table
   ============================================ */
.comparison-table-wrap {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-white);
  font-size: 0.95rem;
}

.comparison-table th,
.comparison-table td {
  padding: 16px 20px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.comparison-table th {
  background: var(--bg-gray);
  font-weight: 700;
  color: var(--text-primary);
  font-size: 0.9rem;
}

.comparison-table th:first-child {
  border-top-left-radius: var(--radius-lg);
}

.comparison-table th:last-child {
  border-top-right-radius: var(--radius-lg);
}

.comparison-table tr:last-child td:first-child {
  border-bottom-left-radius: var(--radius-lg);
}

.comparison-table tr:last-child td:last-child {
  border-bottom-right-radius: var(--radius-lg);
}

.comparison-table tr:hover td {
  background: var(--bg-light);
}

.comparison-table td:first-child {
  font-weight: 600;
  color: var(--text-primary);
}

.comparison-check {
  color: var(--secondary);
}

.comparison-cross {
  color: var(--danger);
}

.comparison-check svg,
.comparison-cross svg {
  width: 20px;
  height: 20px;
}

/* Highlight Chrome column */
.comparison-table th.chrome-col,
.comparison-table td.chrome-col {
  background: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.comparison-table tr:hover td.chrome-col {
  background: #d2e3fc;
}

/* ============================================
   FAQ
   ============================================ */
.faq-list {
  max-width: 800px;
  margin: 0 auto;
}

.faq-item {
  background: var(--bg-white);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  margin-bottom: 12px;
  overflow: hidden;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--primary);
}

.faq-question {
  width: 100%;
  padding: 20px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  text-align: left;
  transition: var(--transition);
}

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

.faq-question svg {
  width: 20px;
  height: 20px;
  color: var(--text-muted);
  transition: var(--transition);
  flex-shrink: 0;
}

.faq-item.open .faq-question svg {
  transform: rotate(180deg);
  color: var(--primary);
}

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

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

.faq-answer-inner {
  padding: 0 24px 20px;
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  background: var(--text-primary);
  color: #fff;
  padding: 60px 0 30px;
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

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

.footer-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.footer-brand svg {
  width: 24px;
  height: 24px;
}

.footer-desc {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.7);
  line-height: 1.7;
}

.footer-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: #fff;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

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

.footer-links a {
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.7);
  transition: var(--transition);
}

.footer-links a:hover {
  color: #fff;
}

.footer-divider {
  border: none;
  height: 1px;
  background: rgba(255, 255, 255, 0.1);
  margin-bottom: 24px;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-copyright {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.6);
  line-height: 1.6;
}

.footer-verify {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--secondary);
}

.footer-verify svg {
  width: 18px;
  height: 18px;
}

/* ============================================
   Download Page Specific Styles
   ============================================ */
.download-hero {
  padding: calc(var(--nav-height) + 60px) 0 60px;
  background: linear-gradient(135deg, var(--bg-light) 0%, #e8f0fe 100%);
  text-align: center;
}

.download-hero-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

.download-hero-title {
  font-size: 2.6rem;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.download-hero-desc {
  font-size: 1.1rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.download-main-card {
  background: var(--bg-white);
  border-radius: var(--radius-xl);
  padding: 48px;
  max-width: 600px;
  margin: 0 auto;
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--border);
}

.download-main-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-light);
  border-radius: var(--radius-lg);
}

.download-main-icon svg {
  width: 44px;
  height: 44px;
  color: var(--primary);
}

.download-main-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.download-main-version {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.download-main-btn {
  width: 100%;
  margin-bottom: 16px;
}

.download-main-meta {
  display: flex;
  justify-content: center;
  gap: 24px;
  font-size: 0.85rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}

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

/* Platform Download Cards (Download Page) */
.dl-platform-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.dl-platform-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 32px;
  border: 1px solid var(--border);
  transition: var(--transition);
}

.dl-platform-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
}

.dl-platform-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 20px;
}

.dl-platform-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  background: var(--bg-gray);
}

.dl-platform-icon svg {
  width: 28px;
  height: 28px;
}

.dl-platform-name {
  font-size: 1.2rem;
  font-weight: 700;
}

.dl-platform-version {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.dl-platform-info {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.6;
}

.dl-platform-steps {
  background: var(--bg-light);
  border-radius: var(--radius-md);
  padding: 16px;
  margin-bottom: 20px;
}

.dl-platform-steps-title {
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 10px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.dl-platform-steps ol {
  padding-left: 18px;
}

.dl-platform-steps ol li {
  list-style: decimal;
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 4px;
}

.dl-platform-btn {
  width: 100%;
}

/* Installation Guide */
.guide-section {
  max-width: 800px;
  margin: 0 auto;
}

.guide-step {
  display: flex;
  gap: 24px;
  margin-bottom: 40px;
  position: relative;
}

.guide-step:not(:last-child)::after {
  content: '';
  position: absolute;
  left: 24px;
  top: 56px;
  width: 2px;
  height: calc(100% - 16px);
  background: var(--border);
}

.guide-step-num {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.1rem;
  flex-shrink: 0;
  position: relative;
  z-index: 1;
}

.guide-step-content {
  flex: 1;
  padding-top: 4px;
}

.guide-step-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.guide-step-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.guide-step-img {
  margin-top: 16px;
  background: var(--bg-gray);
  border-radius: var(--radius-md);
  padding: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 160px;
  border: 1px dashed var(--border);
}

.guide-step-img svg {
  width: 80px;
  height: 80px;
  color: var(--text-muted);
}

/* System Requirements */
.sysreq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.sysreq-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: 28px;
  border: 1px solid var(--border);
}

.sysreq-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.sysreq-header svg {
  width: 28px;
  height: 28px;
  color: var(--primary);
}

.sysreq-title {
  font-size: 1.1rem;
  font-weight: 700;
}

.sysreq-list li {
  display: flex;
  justify-content: space-between;
  padding: 10px 0;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--bg-gray);
}

.sysreq-list li:last-child {
  border-bottom: none;
}

.sysreq-label {
  color: var(--text-secondary);
}

.sysreq-value {
  color: var(--text-primary);
  font-weight: 600;
}

/* Changelog */
.changelog-list {
  max-width: 800px;
  margin: 0 auto;
}

.changelog-item {
  display: flex;
  gap: 24px;
  padding: 24px;
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  margin-bottom: 16px;
  transition: var(--transition);
}

.changelog-item:hover {
  box-shadow: var(--shadow-md);
}

.changelog-badge {
  flex-shrink: 0;
  padding: 8px 14px;
  background: var(--primary-light);
  color: var(--primary);
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 700;
  height: fit-content;
}

.changelog-content h4 {
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.changelog-date {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.changelog-points {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.7;
}

.changelog-points li {
  list-style: disc inside;
  margin-bottom: 4px;
}

/* Security Banner */
.security-banner {
  background: linear-gradient(135deg, #e8f5e9 0%, #c8e6c9 100%);
  border-radius: var(--radius-lg);
  padding: 32px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.security-icon {
  width: 64px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--secondary);
  border-radius: 50%;
  flex-shrink: 0;
}

.security-icon svg {
  width: 32px;
  height: 32px;
  color: #fff;
}

.security-content h3 {
  font-size: 1.2rem;
  font-weight: 700;
  color: #1b5e20;
  margin-bottom: 6px;
}

.security-content p {
  font-size: 0.95rem;
  color: #2e7d32;
  line-height: 1.6;
}

/* ============================================
   SEO / zh-cn Page Styles
   ============================================ */
.seo-article {
  max-width: 800px;
  margin: 0 auto;
}

.seo-article h2 {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 48px 0 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--primary-light);
}

.seo-article h3 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 32px 0 14px;
}

.seo-article p {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

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

.seo-article ul li,
.seo-article ol li {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: 8px;
  list-style: disc;
}

.seo-article ol li {
  list-style: decimal;
}

.seo-cta-box {
  background: linear-gradient(135deg, var(--primary-light) 0%, #e8f0fe 100%);
  border-radius: var(--radius-lg);
  padding: 40px;
  text-align: center;
  margin: 40px 0;
  border: 2px solid var(--primary);
}

.seo-cta-box h3 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 12px;
}

.seo-cta-box p {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

/* ============================================
   Utility Classes
   ============================================ */
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 32px; }
.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mb-4 { margin-bottom: 32px; }

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .dl-platform-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-main {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  :root {
    --nav-height: 64px;
  }
  
  .hero-inner {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-title {
    font-size: 2.2rem;
  }
  
  .hero-desc {
    margin-left: auto;
    margin-right: auto;
  }
  
  .hero-actions {
    justify-content: center;
  }
  
  .hero-meta {
    justify-content: center;
  }
  
  .hero-visual {
    order: -1;
  }
  
  .hero-visual-bg {
    width: 280px;
    height: 280px;
  }
  
  .section-title {
    font-size: 1.8rem;
  }
  
  .features-grid,
  .platforms-grid,
  .reviews-grid,
  .stats-grid,
  .dl-platform-grid,
  .sysreq-grid {
    grid-template-columns: 1fr;
  }
  
  .detail-block,
  .detail-block.reverse {
    grid-template-columns: 1fr;
    direction: ltr;
  }
  
  .detail-block.reverse > * {
    direction: ltr;
  }
  
  .footer-main {
    grid-template-columns: 1fr;
    gap: 32px;
  }
  
  .footer-bottom {
    flex-direction: column;
    text-align: center;
  }
  
  .mobile-toggle {
    display: flex;
  }
  
  .nav-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    flex-direction: column;
    padding: 20px;
    gap: 8px;
    border-bottom: 1px solid var(--border);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
  }
  
  .nav-menu.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }
  
  .nav-link {
    width: 100%;
    text-align: center;
  }
  
  .nav-cta {
    width: 100%;
    text-align: center;
  }
  
  .comparison-table-wrap {
    font-size: 0.85rem;
  }
  
  .comparison-table th,
  .comparison-table td {
    padding: 12px 14px;
  }
  
  .download-main-card {
    padding: 32px 24px;
  }
  
  .download-hero-title {
    font-size: 2rem;
  }
  
  .security-banner {
    flex-direction: column;
    text-align: center;
  }
  
  .guide-step {
    gap: 16px;
  }
  
  .guide-step-num {
    width: 40px;
    height: 40px;
    font-size: 1rem;
  }
  
  .changelog-item {
    flex-direction: column;
    gap: 12px;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.8rem;
  }
  
  .section-title {
    font-size: 1.5rem;
  }
  
  .btn-large {
    padding: 14px 28px;
    font-size: 1rem;
  }
  
  .feature-card,
  .platform-card,
  .review-card,
  .stat-card {
    padding: 24px 20px;
  }
}