While there isn't a way to change the size of the popup, it's certainly something our developers could consider in a future update.
You may want to add a feature request or vote on an existing one.
How can I submit a feature request or idea for an improvement to the RescueGroups.org services?
MichelleAdd your comment...
How can we increase the size of the video popups on the animal detail page? It currently popups to about 500px wide. We are using youtube to upload videos and embed as an URL.
Here's an example: https://www.oaklandanimalservices.org/test-page-dogs/#action_0=pet&animalID_0=18071762&petIndex_0=44