create and position responsive header logo throughout site

I have both a static image logo and an animated logo that I would like to have on my site and positioned in the top left corner of the screen. Not sure if i want to use the animation or the static image but both have transparent backgrounds as i'd like to, whichever one i use, just overlay them over top of the background video currently embedded in my site. Can't figure out how to do this. Using the customizer it's making my page scroll down to see the background video, or if i use the "logo" option it is the small circular logo which is not what i'm going for. The image size is 1920x1080 though i'd like to resize it to about half that, and then have it resize responsively across other devices. Can you please advise on how to do this? Thank you