如何在div中间显示不同背景颜色的文本？

<div id="myDiv">这是一个示例文本</div>

#myDiv {
  width: 300px;
  height: 200px;
  text-align: center;
  display: flex;
  align-items: center;
  justify-content: center;
}

#myDiv::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 50%;
  height: 100%;
  background-color: red;
}

#myDiv::after {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 50%;
  height: 100%;
  background-color: blue;
}

#myDiv {
  color: white;
  font-size: 24px;
  z-index: 1;
}