how to adjust YouTube video width

The youtube video on the page you linked to is embedded like this:
<div class="fluid-width-video-wrapper" style="padding-top: 56.25%; max-width: 70%;"><iframe frameborder="0" allowfullscreen="" src="//www.youtube.com/embed/5-qIuk-RxT8" id="fitvid384833"></iframe></div>

so

span.embed-youtube {
max-width: 560px;
max-height: 315px;
}

does not get applied there.
You’ll have to add some css that targets your div:

div.fluid-width-video-wrapper {
...something here...
}

You’re right.

I used that one

/*YOuTube video wrapper*/
div.fluid-width-video-wrapper {
width: 80%;
height: 80%;
}

The strange to this is that the max-width & max-height do not work. Only the widt and height percentage.

If you have any explanation then i’m glad to here it.
Thank you

ok if I may add a very odd querry here:

I am trying to post a YouTube video after noit doing so for some time. When I try, the video remains the proper size when viewed, but there is a large bblack band on top and bottom which creates a perfect square.

So when I try to adjust the size in WordPress Editor, it only stays perfectly square.

So… when I embed (or simply use the WordPress way, and the dimensions are 560×315, the resulting square i see in the CMS is 560×560. When I preview it, the video is correct but there is a black part top and bottom making it perfectly square.

Thanks in advance.