proko

import { useState, useEffect } from 'react';
import client from 'braintree-web/client';
import hostedFields from 'braintree-web/hosted-fields';

const fieldsInnerStyles = {
  input: {
    'font-size': '14px',
  },
  'input.invalid': {
    color: 'red',

proko

.visually-hidden { 
    clip: rect(1px, 1px, 1px, 1px); 
    height: 1px; 
    overflow: hidden; 
    position: absolute; 
    white-space: nowrap; 
    width: 1px; 
}

//********//

proko

###Negative and Positive LookAhead

Negative lookahead is indispensable if you want to match something not followed by something else. When explaining character classes, this tutorial explained why you cannot use a negated character class to match a q not followed by a u. Negative lookahead provides the solution: q(?!u). The negative lookahead construct is the pair of parentheses, with the opening parenthesis followed by a question mark and an exclamation point. Inside the lookahead, we have the trivial regex u.

Positive lookahead works just the same. q(?=u) matches a q that is followed by a u, without making the u part of the match. The positive lookahead construct is a pair of parentheses, with the opening parenthesis followed by a question mark and an equals sign.

http://www.regular-expressions.info/lookaround.html