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                <!-- Simply add the multiple attribute! -->
<input type="email" inputmode="text" multiple />

<p>The input above accepts multiple e-mail addresses, each separated by a comma.<br />The built-in browser validation rules will validate each entry.</p>

<p><em>⚠️ Note that the email keyboard layout on iOS does <b>not</b> include a comma. To work around this limitation, we manually override the <code>inputmode</code> to <code>text</code>. That way we still have the built-in browser validation rules, and a means to type in a comma.</em></p>


                input {
	border: 2px solid black;
	font-size: 2em;
	display: block;
	width: 100%;
	margin: 5rem auto;

input:focus {
	outline: none; /* To make sure you see the border-color change as you type */

input:invalid {
	border-color: red;

input:valid {
	border-color: green;

* {
	box-sizing: border-box;

body {
	text-align: center;
	max-width: 40em;
	width: 90%;
	margin: 0 auto;
	font-family: -apple-system, BlinkMacSystemFont, avenir next, avenir, helvetica neue, helvetica, Ubuntu, roboto, noto, segoe ui, arial, sans-serif;