JSFiddle - React, Tailwind, and code Playground
by nobuts
HTML
<script>
function checkValue() {
var linkemail=document.forms["theForm"]["linkemail"].checked
if (linkemail) {
document.getElementById('xtraInfo').style.display='';
} else {
document.getElementById('xtraInfo').style.display='none';
}
}
</script>
<form id="theForm" name="theForm" method="post" action="">
<input type="checkbox" name="linkemail" value="y" onclick="return checkValue(this)" /> Check here to link your email.
<div id="xtraInfo" style="display:none;">
Email <input name="name" type="text" id="name" />
</div>
</form>