如何添加psuedo元素:使用REACT之后

npm install styled-components

import styled from 'styled-components';

const StyledElement = styled.div`
  /* 元素的样式 */

  ::after {
    /* 伪元素的样式 */
  }
`;

const StyledButton = styled.button`
  background-color: blue;
  color: white;
  padding: 10px;
  border: none;
  position: relative;

  ::after {
    content: "";
    position: absolute;
    top: 50%;
    left: 0;
    width: 100%;
    height: 1px;
    background-color: red;
    transform: translateY(-50%);
  }
`;

function App() {
  return (
    <StyledButton>
      Click me
    </StyledButton>
  );
}