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

:root {
  --primary: #2aabee;
  --primary-dark: #229ed9;
  --text: #222;
  --text-light: #666;
  --bg: #fff;
  --bg-light: #f4f8fb;
  --border: #e8eef3;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  line-height: 1.7;
  background: var(--bg);
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color 0.2s;
}

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

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 1px 4px rgba(0,0,0,0.04);
}

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

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: 700;
  color: var(--primary);
}

.logo img {
  width: 36px;
  height: 36px;
}

.nav {
  display: flex;
  gap: 28px;
  list-style: none;
}

.nav a {
  color: var(--text);
  font-size: 15px;
  font-weight: 500;
}

.nav a:hover,
.nav a.active {
  color: var(--primary);
}

.btn-download {
  display: inline-block;
  background: var(--primary);
  color: #fff !important;
  padding: 10px 24px;
  border-radius: 24px;
  font-weight: 600;
  font-size: 15px;
  transition: background 0.2s;
}

.btn-download:hover {
  background: var(--primary-dark);
  color: #fff !important;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #e8f4fd 0%, #f0f8ff 50%, #fff 100%);
  padding: 80px 0 60px;
  text-align: center;
}

.hero h1 {
  font-size: 42px;
  font-weight: 800;
  margin-bottom: 16px;
  color: var(--text);
}

.hero p {
  font-size: 18px;
  color: var(--text-light);
  max-width: 640px;
  margin: 0 auto 32px;
}

.hero .btn-download {
  font-size: 17px;
  padding: 14px 36px;
}

/* Features */
.features {
  padding: 70px 0;
}

.section-title {
  text-align: center;
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 48px;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.feature-card {
  background: var(--bg-light);
  border-radius: 12px;
  padding: 28px 24px;
  text-align: center;
  border: 1px solid var(--border);
  transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(42,171,238,0.12);
}

.feature-icon {
  width: 56px;
  height: 56px;
  background: var(--primary);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  font-size: 24px;
  color: #fff;
}

.feature-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.feature-card p {
  font-size: 14px;
  color: var(--text-light);
}

/* Blog section */
.blog-section {
  padding: 60px 0 80px;
  background: var(--bg-light);
}

.blog-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.blog-card {
  background: var(--bg);
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border);
  transition: box-shadow 0.2s;
}

.blog-card:hover {
  box-shadow: 0 6px 20px rgba(0,0,0,0.08);
}

.blog-card-body {
  padding: 22px;
}

.blog-card h3 {
  font-size: 16px;
  line-height: 1.5;
  margin-bottom: 10px;
}

.blog-card h3 a {
  color: var(--text);
}

.blog-card h3 a:hover {
  color: var(--primary);
}

.blog-card p {
  font-size: 13px;
  color: var(--text-light);
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.blog-date {
  font-size: 12px;
  color: #999;
  margin-top: 12px;
}

/* Download page */
.download-hero {
  padding: 60px 0 40px;
  text-align: center;
  background: var(--bg-light);
}

.download-hero h1 {
  font-size: 36px;
  margin-bottom: 12px;
}

.download-hero p {
  color: var(--text-light);
  font-size: 16px;
  max-width: 560px;
  margin: 0 auto;
}

.download-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  padding: 50px 0 80px;
}

.download-card {
  text-align: center;
  padding: 36px 24px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--bg);
}

.download-card .platform-icon {
  font-size: 48px;
  margin-bottom: 16px;
}

.download-card h3 {
  font-size: 18px;
  margin-bottom: 8px;
}

.download-card p {
  font-size: 14px;
  color: var(--text-light);
  margin-bottom: 20px;
}

.download-info {
  padding: 40px 0 60px;
}

.download-info h2 {
  font-size: 22px;
  margin-bottom: 16px;
}

.download-info p {
  color: var(--text-light);
  margin-bottom: 12px;
}

/* Article page */
.article-header {
  padding: 50px 0 30px;
  border-bottom: 1px solid var(--border);
}

.article-header h1 {
  font-size: 32px;
  line-height: 1.4;
  margin-bottom: 12px;
}

.article-meta {
  font-size: 14px;
  color: #999;
}

.article-content {
  padding: 40px 0 60px;
  max-width: 760px;
}

.article-content h2 {
  font-size: 22px;
  margin: 32px 0 14px;
}

.article-content p {
  margin-bottom: 16px;
  color: #444;
}

.article-content ul {
  margin: 12px 0 16px 24px;
  color: #444;
}

.article-content li {
  margin-bottom: 8px;
}

.breadcrumb {
  padding: 16px 0;
  font-size: 14px;
  color: var(--text-light);
}

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

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

/* Footer */
.site-footer {
  background: #1a1a2e;
  color: #ccc;
  padding: 40px 0 24px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 24px;
  margin-bottom: 24px;
}

.footer-col h4 {
  color: #fff;
  font-size: 15px;
  margin-bottom: 12px;
}

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

.footer-col li {
  margin-bottom: 8px;
}

.footer-col a {
  color: #aaa;
  font-size: 14px;
}

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

.footer-bottom {
  border-top: 1px solid #333;
  padding-top: 20px;
  text-align: center;
  font-size: 13px;
  color: #777;
}

/* Responsive */
@media (max-width: 768px) {
  .features-grid,
  .blog-grid,
  .download-cards {
    grid-template-columns: 1fr;
  }

  .hero h1 {
    font-size: 28px;
  }

  .nav {
    gap: 16px;
    font-size: 14px;
  }

  .header-inner {
    flex-wrap: wrap;
    height: auto;
    padding: 12px 0;
    gap: 12px;
  }
}