/* 全局样式设置 */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  font-family: 'Roboto', Arial, sans-serif;
  line-height: 1.6;
  color: #f0f4f8;
  background: linear-gradient(135deg, #1a1a40, #2c2c7f, #4c4cff);
  background-size: 300% 300%;
  animation: gradientShift 15s infinite alternate;
  overflow-x: hidden;
}
@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  100% { background-position: 100% 50%; }
}
h1, h2, h3 {
  font-weight: bold;
  color: #ffffff;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}
.header {
  text-align: center;
  padding: 50px 20px;
  position: relative;
}
.header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.1);
  z-index: -1;
}
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}
.card {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  padding: 20px;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
  overflow: hidden;
}
.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
}
.card img {
  width: 100%;
  height: auto;
  border-radius: 8px;
  margin-bottom: 15px;
}
.button {
  display: inline-block;
  background: #4c4cff;
  color: white;
  padding: 10px 20px;
  border-radius: 25px;
  transition: background-color 0.3s ease;
  text-decoration: none;
}
.button:hover {
  background: #2c2c7f;
}
pre {
  background: #1a1a40;
  color: #d4d4d4;
  padding: 15px;
  border-radius: 8px;
  overflow-x: auto;
}
table {
  width: 100%;
  border-collapse: collapse;
  margin: 20px 0;
}
th, td {
  padding: 10px;
  text-align: left;
  border: 1px solid #ccc;
}
@media (max-width: 768px) {
  .grid {
    grid-template-columns: 1fr;
  }
}