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	<input />
	<button type="submit">submit</button>

	<p>Demo for <a href="" target="_top"></a></p>


                form button[type="submit"] {
	position: relative;
	overflow: hidden;
	background-color: rgba(0,128,0,1);
	color: white;
	border: 0;
	padding: 0.5em 0.7em;
} button[type="submit"] {
	background-color: rgba(0,128,0,0.7);
	outline: 0;
} button[type="submit"]::before {
	position: absolute;
	content: '';
	height: 0.2em;
	left: 0;
	right: 0;
	top: 0;
	background: green;
	animation: move 1s linear infinite; 

@keyframes move {
	0% {
		transform: translateX(-100%);
	100% {
		transform: translateX(100%);

body {
	height: 100vh;
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;

footer {
	margin-top: 5em;
	font-style: italic;
	font-size: 0.8em;


                // Prevent Double Submits
document.querySelectorAll('form').forEach(form => {
	form.addEventListener('submit', (e) => {
		// Prevent if already submitting
		if (form.classList.contains('is-submitting')) {
			e.preventDefault();'Successive submit suppressed');
		// Add a visual indicator to show the user it is submitting

// Extra snippet here to also prevent form submissions the first submit
// as a viewer of this demo would otherwise be guided to outside of CodePen …
document.querySelectorAll('form').forEach(form => {
	form.addEventListener('submit', e => {