I was happy to see that embedding YouTube videos work great by using the following tags in a forum post

Minus the *

[*youtube]KF0gsbQKhD8[/youtube]

But on my forum and on this forum also, the video overflows the page and won't resize properly when viewing the post both on the blog or from a forum post when viewing it from a mobile device. It looks fine from a desktop PC though.

Not sure where to look to fix this, is the file that controls this part of the bootstrap template CSS or a PHP file?

Here's an example:

file location:

lib/BBcode.lib.php

search:

iframe width="560" height="315"

replace with:

iframe style="width: 100%;height: 500px;"

example::

<iframe style="width: 100%;height: 500px;" src="//www.youtube.com/embed/' .$match[1]. '" frameborder="0" allowfullscreen></iframe>

Perfect, thank you that's exactly what I was looking for.

  You're welcome