JSFiddle - React, Tailwind, and code Playground
HTML
<button id='foo'>Foo</button>
CSS
#foo {
display: none;
opacity: 0;
transition: opacity .5s ease-in-out;
-moz-transition: opacity .5s ease-in-out;
-webkit-transition: opacity .5s ease-in-out;
}
#foo.fade-in {
opacity: 1;
}
JavaScript
$('#foo').show(0, function() {
$(this).addClass('fade-in');
});