javascript - 渲染CSS样式应用了React无状态功能语句

Question

我正在尝试在 React.js 中渲染用无状态功能组件编写的组件。当我尝试渲染下面的代码时，该元素没有显示。 React 和 React-Dom 脚本文件已正确插入。

const showMe = () => {
  return (
    <div className="hi"></div>
  )
};

ReactDOM.render(showMe, document.getElementById("target"));

#target {
  position:absolute;
  left:0;
  right:0;
  margin:0 auto;
  top:50%;
  transform:translateY(-50%);
  border:1px solid red;
  width:600px;
  height:500px;
}

.hi {
  border:1px solid blue;
  position:absolute;
  width:50%;
  height:40%;
  left:0;
  right:0;
  margin:0 auto;
  top:50%;
  transform:translateY(-50%);
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
<div id="target">
</div>

Answer 1

const ShowMe = () => {
  return (
    <div className="hi"></div>
  )
};

ReactDOM.render(<ShowMe />, document.getElementById("target"));

#target {
  position:absolute;
  left:0;
  right:0;
  margin:0 auto;
  top:50%;
  transform:translateY(-50%);
  border:1px solid red;
  width:600px;
  height:500px;
}

.hi {
  border:1px solid blue;
  position:absolute;
  width:50%;
  height:40%;
  left:0;
  right:0;
  margin:0 auto;
  top:50%;
  transform:translateY(-50%);
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>
<div id="target">
</div>