A jQuery Plugin To Enjoy The Videos More: Allofthelights.js
Allofthelights.js is a jQuery plugin that can change the opacity of the whole webpage but leave the video player.
This is for helping the user to easily focus on the video and there is built-in support for YouTube, Vimeo, DailyMotion.. and custom players can be added too.
It works with multiple players on the same page and supports responsive layouts/players with no issues.
The animation speed, background color and opacity can all be customized an callback functions exist.