Redefinition cssVars

If the application theme is set via cssVars and these variables need to be redefined when launching the application 1 time.

import React from 'react';
import ReactDOM from 'react-dom';
import { appendStyles } from 'react-append-styles';

// From webpack or backend
const VARS_CONFIG = { '--my-app-headerHeight': '30px' };

if (VARS_CONFIG) {
  appendStyles({ 'div[data-theme]': VARS_CONFIG });
}

ReactDOM.render(<div data-theme>My App</div>, document.querySelector('#root'));

info

See appendStyles API