title: how do you define the proptypes for the css classes that are passed from parent component?
body: <p>here i am trying to define the props for the className which will be later passed by other parent components..</p>
  
  <pre><code>import React from 'react';
  import PropTypes from 'prop-types';
  
  const ButtonArrow = (props) =&gt; {
    const {
      className, width, height, fill
    } = props;
    return (
      &lt;svg
        className={props.className}
        xmlns="http://www.w3.org/2000/svg"
        width={props.width}
        height={props.height}
        fill={props.fill}
        viewBox="0 0 18 18"
      &gt;
        &lt;path d="M9 3L7.94 4.06l4.19 4.19H3v1.5h9.13l-4.19 4.19L9 15l6-6z" /&gt;
      &lt;/svg&gt;
    );
  };
  </code></pre>