/* ===== Site 1: Corporate Blue Theme ===== */
/* Design: Professional corporate style with blue accent */

:root {
  --primary: #2563EB;
  --primary-dark: #1E40AF;
  --primary-light: #DBEAFE;
  --text: #1E293B;
  --text-secondary: #64748B;
  --bg: #FFFFFF;
  --bg-alt: #F1F5F9;
  --border: #E2E8F0;
  --shadow: 0 4px 6px -1px rgba(0,0,0,0.1);
  --shadow-lg: 0 20px 25px -5px rgba(0,0,0,0.1);
  --radius: 12px;
  --radius-sm: 8px;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  line-height: 1.6;
  background: var(--bg);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== Header & Nav ===== */
.header {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 4px;
  list-style: none;
}

.nav-links a {
  display: block;
  padding: 8px 18px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: all 0.2s;
}

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

.nav-links a.active {
  color: var(--primary);
  background: var(--primary-light);
}

/* ===== Hero Section ===== */
.hero {
  background: linear-gradient(180deg, #EFF6FF 0%, var(--bg) 100%);
  padding: 80px 0 100px;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--primary-light);
  color: var(--primary-dark);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 24px;
}

.hero h1 {
  font-size: 52px;
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: 20px;
  color: var(--text);
  letter-spacing: -1px;
}

.hero h1 span {
  color: var(--primary);
}

.hero-subtitle {
  font-size: 20px;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto 36px;
  line-height: 1.7;
}

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

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 16px;
  font-weight: 600;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.2s;
  font-family: inherit;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-lg {
  padding: 16px 40px;
  font-size: 18px;
}

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

.section-title {
  font-size: 36px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
}

.section-desc {
  text-align: center;
  color: var(--text-secondary);
  font-size: 18px;
  max-width: 600px;
  margin: 0 auto 56px;
}

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

/* ===== Feature Cards ===== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  transition: all 0.2s;
}

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

.feature-icon {
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--primary-light);
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
  color: var(--primary);
}

.feature-card h3 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 10px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.7;
}

/* ===== Platform Download Cards ===== */
.platforms-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  margin-top: 40px;
}

.platform-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px 24px;
  text-align: center;
  transition: all 0.2s;
}

.platform-card:hover {
  box-shadow: var(--shadow);
  border-color: var(--primary);
}

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

.platform-card h4 {
  font-size: 18px;
  margin-bottom: 8px;
}

.platform-card p {
  color: var(--text-secondary);
  font-size: 14px;
  margin-bottom: 16px;
}

.platform-card .btn {
  width: 100%;
  padding: 12px;
  font-size: 15px;
}

/* ===== Detail Blocks ===== */
.detail-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  margin-bottom: 64px;
}

.detail-block:nth-child(even) {
  direction: rtl;
}

.detail-block:nth-child(even) > * {
  direction: ltr;
}

.detail-block h3 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 16px;
}

.detail-block p {
  color: var(--text-secondary);
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 12px;
}

.detail-visual {
  background: var(--bg-alt);
  border-radius: var(--radius);
  height: 280px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
}

/* ===== Reviews ===== */
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
}

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

.review-stars {
  color: #F59E0B;
  font-size: 18px;
  margin-bottom: 12px;
}

.review-card p {
  color: var(--text);
  font-size: 15px;
  line-height: 1.7;
  margin-bottom: 16px;
}

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

.review-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--primary-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  color: var(--primary);
  font-size: 14px;
}

.review-author span {
  font-weight: 600;
  font-size: 14px;
}

/* ===== Stats ===== */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  text-align: center;
}

.stat-item h4 {
  font-size: 40px;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: 8px;
}

.stat-item p {
  color: var(--text-secondary);
  font-size: 15px;
}

/* ===== Comparison Table ===== */
.comparison-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 32px;
  font-size: 15px;
}

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

.comparison-table th {
  background: var(--bg-alt);
  font-weight: 600;
  color: var(--text);
}

.comparison-table td {
  color: var(--text-secondary);
}

.comparison-table tr:hover td {
  background: #FAFBFC;
}

.check-yes { color: #059669; font-weight: 600; }
.check-no { color: #DC2626; }

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

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

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

.faq-question:hover {
  background: var(--bg-alt);
}

.faq-icon {
  color: var(--text-secondary);
  font-size: 20px;
  transition: transform 0.2s;
}

.faq-item.active .faq-icon {
  transform: rotate(180deg);
}

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

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

.faq-answer-inner {
  padding: 0 24px 20px;
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.7;
}

/* ===== Download Page Specific ===== */
.download-hero {
  background: linear-gradient(135deg, #EFF6FF 0%, #DBEAFE 100%);
  padding: 60px 0;
  text-align: center;
}

.download-hero h1 {
  font-size: 42px;
  font-weight: 800;
  margin-bottom: 12px;
}

.download-hero p {
  color: var(--text-secondary);
  font-size: 18px;
  margin-bottom: 32px;
}

.download-main {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 48px;
  max-width: 600px;
  margin: 0 auto;
  text-align: center;
}

.download-main .btn-lg {
  margin-top: 20px;
}

.version-meta {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin: 20px 0;
  font-size: 14px;
  color: var(--text-secondary);
}

.install-guide {
  margin-top: 48px;
}

.guide-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
  margin-top: 32px;
}

.guide-step {
  text-align: center;
  padding: 24px;
}

.step-num {
  width: 40px;
  height: 40px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  margin: 0 auto 16px;
}

.guide-step h4 {
  font-size: 16px;
  margin-bottom: 8px;
}

.guide-step p {
  font-size: 14px;
  color: var(--text-secondary);
}

.sys-req-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 24px;
  margin-top: 32px;
}

.sys-req-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}

.sys-req-card h4 {
  font-size: 18px;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.sys-req-card ul {
  list-style: none;
  font-size: 14px;
  color: var(--text-secondary);
}

.sys-req-card ul li {
  padding: 6px 0;
  border-bottom: 1px solid var(--border);
}

.changelog-list {
  max-width: 800px;
  margin: 32px auto 0;
}

.changelog-item {
  border-left: 3px solid var(--primary);
  padding-left: 24px;
  padding-bottom: 32px;
  position: relative;
}

.changelog-item::before {
  content: '';
  position: absolute;
  left: -7px;
  top: 0;
  width: 12px;
  height: 12px;
  background: var(--primary);
  border-radius: 50%;
}

.changelog-item:last-child {
  border-left-color: transparent;
}

.changelog-item h4 {
  font-size: 18px;
  margin-bottom: 4px;
}

.changelog-date {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.changelog-item ul {
  font-size: 14px;
  color: var(--text-secondary);
  padding-left: 18px;
}

.changelog-item ul li {
  margin-bottom: 4px;
}

/* ===== zh-cn Page Specific ===== */
.article-content {
  max-width: 900px;
  margin: 0 auto;
}

.article-content h2 {
  font-size: 28px;
  font-weight: 700;
  margin: 48px 0 20px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--primary-light);
}

.article-content h3 {
  font-size: 22px;
  font-weight: 600;
  margin: 32px 0 14px;
  color: var(--primary-dark);
}

.article-content p {
  font-size: 16px;
  line-height: 1.9;
  color: var(--text);
  margin-bottom: 16px;
}

.article-content ul, .article-content ol {
  padding-left: 24px;
  margin-bottom: 20px;
}

.article-content li {
  margin-bottom: 10px;
  line-height: 1.8;
}

.tips-box {
  background: #FEF3C7;
  border-left: 4px solid #F59E0B;
  padding: 20px 24px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 24px 0;
}

.tips-box strong {
  color: #92400E;
}

/* ===== Footer ===== */
.footer {
  background: #0F172A;
  color: #94A3B8;
  padding: 40px 0;
  text-align: center;
  font-size: 14px;
}

.footer p {
  margin-bottom: 8px;
}

.footer a {
  color: #CBD5E1;
  text-decoration: none;
}

.footer a:hover {
  color: var(--primary);
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .hero h1 { font-size: 32px; }
  .hero-subtitle { font-size: 16px; }
  .section-title { font-size: 28px; }
  .nav-links { display: none; }
  .features-grid { grid-template-columns: 1fr; }
  .detail-block { grid-template-columns: 1fr; gap: 32px; }
  .detail-block:nth-child(even) { direction: ltr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .comparison-table { font-size: 13px; }
  .comparison-table th, .comparison-table td { padding: 10px 12px; }
  .platforms-grid { grid-template-columns: 1fr; }
  .download-main { padding: 32px 24px; }
  .guide-steps { grid-template-columns: 1fr; }
  .sys-req-grid { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
  .hero { padding: 60px 0 80px; }
  .section { padding: 60px 0; }
  .hero h1 { font-size: 26px; }
  .stats-grid { grid-template-columns: 1fr 1fr; gap: 20px; }
  .stat-item h4 { font-size: 28px; }
}