The simplest and dependency free Youtube modal player.
Download it from the repository and get the files from the dist folder. (Bower and npm will be available soon)
Add the following script after referencing the css and js files:
window.tago.playerbox.init('#play-button', 'youtubeVideoId', 'path/to/loading.gif');
And that's it. You're ready to go.
This is a work in progress, so there are limitations such as using it only once in the same page.