JSFiddle - React, Tailwind, and code Playground

HTML

<a rel="IcF-OsJnkjk" id="video_link" onclick="open_video(this); return false;" style="display:block" href="#">Mostrar Video 1<br /></a>
<a rel="n9AcG0glVu4" id="video_link" onclick="open_video(this); return false;" style="display:block" href="#">Mostrar Video 2<br /></a>
<a rel="Zew6hGsFNXQ" id="video_link" onclick="open_video(this); return false;"style="display:block"  href="#">Mostrar Video 3<br /></a>

JavaScript

function open_video(a){
    a.innerHTML = String(a.innerHTML).replace("Mostrar","Cerrar");
    a.innerHTML += '<iframe width="425" height="349" src="http://www.youtube.com/embed/'+a.rel+'?autoplay=1" frameborder="0" allowfullscreen></iframe>';
    a.onclick = function(){closevideo(a)};
}

function closevideo(a){
    a.innerHTML = String(a.innerHTML).replace("Cerrar","Mostrar");
    iframe = a.getElementsByTagName("iframe")[0];
    iframe.parentNode.removeChild(iframe);
    a.onclick= function(){open_video(this); return false;}
}