如何根据React中css自定义属性的值检查条件

import React, { useState } from 'react';
import './styles.css';

const App = () => {
  const [value, setValue] = useState('');

  const handleChange = (e) => {
    setValue(e.target.value);
  };

  return (
    <div>
      <input
        type="text"
        value={value}
        onChange={handleChange}
        style={{ '--custom-color': value }}
      />
      <div
        className={`box ${value ? 'highlight' : ''}`}
        style={{ '--custom-color': value }}
      >
        {value && `You entered: ${value}`}
      </div>
    </div>
  );
};

export default App;

.box {
  width: 200px;
  height: 200px;
  background-color: var(--custom-color);
  transition: background-color 0.3s ease;
}

.highlight {
  background-color: yellow;
}