Unless I'm missing something, why are you needlessly re-inventing the wheel?
By default, the video players in all 3 top browsers have a full screen button on the far right side of the Player Controls bar (see screenshot). You simply need to include the player control attribute in your <video> tag.
<video controls poster="YOUR_POSTER_IMAGE.jpg">
<source src="YOUR_VIDEO.mp4" type="video/mp4"></source>
<p>Your browser doesn't support HTML5 video. Please upgrade to a modern browser.</p>
Hi Nancy O
Thank you for your reply. I'm aware about the built-in video controls function but I wanted a branded interface, which is a lot harder to replicate, for users to experience, hence why I'm asking for the appropriate coding for video controls.
Many thanks and regards