JSFiddle - React, Tailwind, and code Playground

HTML

<div id="container">
    <iframe width="664" height="390" src="https://www.youtube.com/v/JfYn1og9p-U?autoplay=1&version=3&loop=1&playlist=JfYn1og9p-U&rel=0" frameborder="0" allowfullscreen></iframe>
    <button id="play">Play Now</button>
</div>

CSS

#container{
    position: relative;
}

#play {
    width: 100px;
    height: 100px;
    position: absolute;
    bottom: 10px;
    left: 50%;
    margin-left: -100px;
}