/* 基础样式 */
body {
  font-family: 'Roboto', sans-serif;
  margin: 0;
  padding: 0;
  background: linear-gradient(to bottom, #d4f0d5, #fff);
  color: #333;
  line-height: 1.6;
}
h1, h2, h3 {
  font-weight: bold;
  color: #2a5b2c;
}
p {
  font-weight: lighter;
  color: #444;
}
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  z-index: 1000;
}
.nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 20px;
}
.nav a {
  text-decoration: none;
  color: #2a5b2c;
  font-size: 16px;
  transition: color 0.3s ease;
}
.nav a:hover {
  color: #0078ff;
}
.hero {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: url('https://images.gptkong.com/demo/sample1.png') no-repeat center/cover, linear-gradient(to right, #d4f0d5, #f0f8ff);
  position: relative;
  overflow: hidden;
}
.particle {
  position: absolute;
  width: 10px;
  height: 10px;
  background: rgba(0, 128, 255, 0.5);
  border-radius: 50%;
  animation: move 5s infinite;
}
@keyframes move {
  0% { transform: translateX(0) translateY(0); }
  50% { transform: translateX(100px) translateY(-100px); }
  100% { transform: translateX(0) translateY(0); }
}
.hero-content {
  text-align: center;
  z-index: 1;
}
.hero-content h1 {
  font-size: 48px;
  color: #fff;
  text-shadow: 2px 2px 5px rgba(0, 0, 0, 0.3);
}
.hero-content p {
  font-size: 18px;
  color: #fff;
  margin-top: 20px;
}
.section {
  padding: 60px 20px;
  background: #fff;
  margin-top: 60px;
}
.section:nth-child(even) {
  background: #f9f9f9;
}
.section-title {
  font-size: 32px;
  margin-bottom: 30px;
  text-align: center;
}
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}
.card {
  background: #fff;
  border: 1px solid #ddd;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}
.card img {
  width: 100%;
  height: auto;
  border-radius: 8px;
  margin-bottom: 10px;
}
.code-block {
  background: #f4f4f4;
  padding: 15px;
  border-radius: 5px;
  overflow-x: auto;
  font-family: 'Courier New', monospace;
  font-size: 14px;
  color: #333;
}
@media (max-width: 768px) {
  .hero-content h1 {
    font-size: 36px;
  }
  .section-title {
    font-size: 28px;
  }
}
@media (max-width: 480px) {
  .nav {
    flex-direction: column;
    align-items: flex-start;
  }
  .hero-content h1 {
    font-size: 28px;
  }
}