.bg {
  height: 100px;
  background-color: #aaa;
}

.container2-1 {
  display: flex;
  flex-direction: row; /* 項目在水平方向排列 */
}

.container2-2 {
  display: flex;
  justify-content: center; /* 項目在主軸上居中對齊 */
}

.container2-3 {
  display: flex;
  align-items: center; /* 項目在交叉軸上居中對齊 */
}

.container2-4 {
  display: flex;
  flex-wrap: wrap; /* 允許內容換行 */
  align-content: space-between; /* 行與行之間均勻分佈 */
}

.container2-5 {
  display: flex;
  flex-wrap: wrap; /* 項目超過容器寬度時換行 */
}

.flex-container {
  display: flex; /* 設定為彈性容器 */
  justify-content: space-between; /* 主軸上均勻分佈 */
  align-items: center; /* 交叉軸上居中對齊 */
  height: 100px;
}

.item {
  flex: 1; /* 每個項目均勻分配空間 */
  padding: 10px;
  background-color: #ddd;
  border: 1px solid #ccc;
}

.item2 {
  padding: 10px;
  background-color: #ddd;
  border: 1px solid #ccc;
}