/* 基础样式 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background: #000 url("./photo-1620641788421-7a1c342ea42e.avif") no-repeat
    center center fixed;
  background-size: cover;
  color: #fff;
  line-height: 1.6;
}

.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.7);
  z-index: -1;
}

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

/* 头部导航 */
header {
  background-color: rgba(0, 0, 0, 0.8);
  position: fixed;
  width: 100%;
  z-index: 1000;
  padding: 15px 0;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}

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

.logo {
  font-size: 28px;
  font-weight: bold;
  color: #ff6600;
}

.logo span {
  color: #fff;
}

nav ul {
  display: flex;
  list-style: none;
}

nav ul li {
  margin-left: 30px;
}

nav ul li a {
  color: #fff;
  text-decoration: none;
  font-weight: 500;
  transition: color 0.3s;
}

nav ul li a:hover {
  color: #ff6600;
}

.app-link {
  background-color: #ff6600;
  padding: 8px 20px;
  border-radius: 30px;
  font-weight: bold;
  transition: background-color 0.3s;
}

.app-link:hover {
  background-color: #e55a00;
}

/* 主要内容区域 */
section {
  padding: 100px 0;
}

.hero {
  text-align: center;
  padding-top: 150px;
  padding-bottom: 100px;
}

.hero h1 {
  font-size: 48px;
  margin-bottom: 20px;
  color: #ff6600;
}

.hero p {
  font-size: 20px;
  max-width: 800px;
  margin: 0 auto 30px;
}

.section-title {
  text-align: center;
  margin-bottom: 60px;
  font-size: 36px;
  color: #ff6600;
}

/* 功能区域 */
.features {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  margin-bottom: 80px;
}

.feature {
  flex: 0 0 48%;
  margin-bottom: 40px;
  display: flex;
  align-items: flex-start;
}

.feature-img {
  width: 200px;
  height: 450px;
  background-color: #333;
  border-radius: 20px;
  margin-right: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #999;
  font-size: 14px;
  overflow: hidden;
}

.feature-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.feature-content {
  flex: 1;
}

.feature-content h3 {
  font-size: 24px;
  margin-bottom: 15px;
  color: #ff6600;
}

.feature-content p {
  margin-bottom: 15px;
}

/* 总览图区域 */
.overview {
  text-align: center;
  margin-top: 80px;
}

.overview-img {
  width: 100%;
  max-width: 800px;
  height: 450px;
  background-color: #333;
  margin: 0 auto 30px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #999;
  font-size: 16px;
  overflow: hidden;
}

.overview-img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* 页脚 */
footer {
  background-color: rgba(0, 0, 0, 0.9);
  padding: 50px 0 30px;
  text-align: center;
}

.footer-content {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.contact-email {
  font-size: 18px;
  margin-bottom: 20px;
  color: #ff6600;
}

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

/* 响应式设计 */
@media (max-width: 992px) {
  .feature {
    flex: 0 0 100%;
  }

  .feature-img {
    width: 150px;
    height: 340px;
  }

  .hero h1 {
    font-size: 36px;
  }

  .section-title {
    font-size: 30px;
  }
}

@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
  }

  .logo {
    margin-bottom: 15px;
  }

  nav ul {
    flex-wrap: wrap;
    justify-content: center;
  }

  nav ul li {
    margin: 5px 15px;
  }

  .hero {
    padding-top: 200px;
  }

  .feature {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .feature-img {
    margin-right: 0;
    margin-bottom: 20px;
  }
}

@media (max-width: 576px) {
  .hero h1 {
    font-size: 28px;
  }

  .hero p {
    font-size: 16px;
  }

  .section-title {
    font-size: 24px;
  }

  .feature-img {
    width: 120px;
    height: 270px;
  }
}