* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
}

body {
  background-color: #f5f5f5;
  color: #333;
  line-height: 1.6;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}

header {
  background: linear-gradient(135deg, #1e5799 0%, #207cca 100%);
  color: white;
  padding: 40px 20px;
  text-align: center;
  border-radius: 10px;
  margin-bottom: 30px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  position: relative;
}

.android-only {
  position: absolute;
  top: 10px;
  right: 10px;
  background-color: #3ddc84;
  color: white;
  padding: 5px 10px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: bold;
}

/* 优化5：使用语义化HTML标签 */
h1 {
  font-size: 2.5rem;
  margin-bottom: 15px;
}

h2 {
  font-size: 1.8rem;
  margin-bottom: 15px;
  color: #1e5799;
}

h3 {
  font-size: 1.3rem;
  margin-bottom: 10px;
}

.subtitle {
  font-size: 1.2rem;
  opacity: 0.9;
  margin-bottom: 20px;
}

.app-icon {
  width: 120px;
  height: 120px;
  border-radius: 20px;
  margin: 0 auto 25px;
  display: block;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
  border: 4px solid white;
}

.features {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  margin-bottom: 40px;
  gap: 20px;
}

.feature-card {
  flex: 1 1 300px;
  background: white;
  padding: 25px;
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease;
}

.feature-card:hover {
  transform: translateY(-5px);
}

.feature-icon {
  font-size: 2.5rem;
  color: #1e5799;
  margin-bottom: 15px;
}

.feature-title {
  font-size: 1.3rem;
  margin-bottom: 10px;
  color: #1e5799;
}

.download-section {
  text-align: center;
  margin: 40px 0;
}

.download-btn {
  display: inline-block;
  background-color: #1e5799;
  color: white;
  padding: 15px 30px;
  border-radius: 50px;
  text-decoration: none;
  font-size: 1.2rem;
  font-weight: bold;
  margin: 10px;
  transition: all 0.3s ease;
  box-shadow: 0 4px 12px rgba(30, 87, 153, 0.3);
  position: relative;
  cursor: pointer;
  overflow: hidden;
}
.loading-mask {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.8);
  align-items: center;
  justify-content: center;
  display: none;
}
.loading-icon {
  display: inline-block;
  border: 2px solid #fff;
  border-style: solid;
  border-top-color: transparent;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(360deg);
  }
}

.download-btn:hover {
  background-color: #15467a;
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(30, 87, 153, 0.4);
}

/* 优化6：图片SEO优化 */
.screenshots {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
  margin: 40px 0;
}

.screenshot {
  width: 200px;
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease;
}

.screenshot:hover {
  transform: scale(1.05);
}

.testimonials {
  background-color: white;
  padding: 40px;
  border-radius: 10px;
  margin: 40px 0;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.testimonial {
  margin-bottom: 25px;
}

.testimonial-text {
  font-style: italic;
  margin-bottom: 10px;
}

.testimonial-author {
  font-weight: bold;
  color: #1e5799;
}

footer {
  text-align: center;
  padding: 20px;
  color: #666;
  font-size: 0.9rem;
}

.wechat-tip {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.8);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  color: white;
  padding: 20px;
  text-align: center;
}

.wechat-tip-content {
  background-color: white;
  color: #333;
  padding: 30px;
  border-radius: 10px;
  max-width: 500px;
}

.wechat-tip h2 {
  color: #1e5799;
  margin-bottom: 20px;
}

.wechat-tip-btn {
  display: inline-block;
  background-color: #1e5799;
  color: white;
  padding: 10px 20px;
  border-radius: 5px;
  text-decoration: none;
  margin-top: 20px;
}

@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.5rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .feature-card {
    flex: 1 1 100%;
  }

  .screenshot {
    width: 150px;
  }
}