Why is my logo moving?

EDIT: I think I’ve found a solution, but any input will be appreciated.

So my website (vastava.github.io) is in its beginning stages, but whenever I change the size of the window, my logo seems to move (see photos, or experiment for yourself on the website).

does anyone have any idea why it would do this? the code is publicly available on my github. Thanks!

The CSS position for that element is fixed. In the absence of top, bottom, left or right values, the defaults are used. These values are relative to the size of the viewport. So when the size of the viewport changes, the position of a fixed element may change relative to other elements in the document. This is what you’re seeing.