config-overrides.js

const { override, fixBabelImports, addLessLoader } = require('customize-cra');

module.exports = override(
  fixBabelImports('import', {
    libraryName: 'antd',
    libraryDirectory: 'es',
    style: true
  }),
  addLessLoader({
    javascriptEnabled: true,
    modifyVars: {
      "@primary-color": "#f2a94a",
      "@font-family": "'Open Sans', sans-serif",
    }
  })
);