For each button you can use one of 7 pre-defined styles. Also, you can specify custom background/text color and add icon from 5 pre-defined icon sets.
Buttons
Icons
There is a 5 pre-packaged icon libraries: FontAwesome, Open Iconic, Typicons, Entypo and Linecons.
Images
Video
You can use any source of video: YouTube, Vimeo, Twitch, etc.. Just paste URL of video and give us the rest.