<div class="container">
  <div class="item">列 1</div>
  <div class="item">列 2</div>
  <div class="item">列 3</div>
</div>

.container {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 10px; /* 每列之間的間距 */
}

.item {
  background-color: #4CAF50;
  color: white;
  padding: 20px;
  text-align: center;
}