See demo
npm install happy-inputs<!DOCTYPE html>
<html>
<head>
<title>Happy</title>
<link rel="stylesheet" type="text/css" href="./node_modules/happy-inputs/src/happy.css">
<script type="module">
import happy from './node_modules/happy-inputs/src/index.js';
Happy.init();
</script>
</head>
<body>
<!-- Default (black) radio -->
<label>
<input class="happy" type="radio" name="animal" value="dog"> A dog
</label>
<!-- Default (black) checkbox -->
<label>
<input class="happy" type="checkbox" name="hungry"> Hungry
</label>
<!-- Colored (as you are used to from Bootstrap) radio -->
<label>
<input class="happy success" type="radio" name="animal" value="dog"> A dog
</label>
<!-- Colored (as you are used to from Bootstrap) checkbox -->
<label>
<input class="happy primary" type="checkbox" name="hungry"> Hungry
</label>
</body>
</html><!DOCTYPE html>
<html>
<head>
<title>Happy</title>
<link rel="stylesheet" type="text/css" href="./node_modules/happy-inputs/src/happy.css">
<script src="https://cdn.jsdelivr.net/npm/happy-inputs@2.1.0/src/nomodule-es5-fallback.js"></script>
<script>
var happy = new Happy;
happy.init();
</script>
<!-- ... -->
</head>
<body>