Larger head image after update 3.5.3

After the 3.5.3 update, my image is much larger.

Cause of the problem:
CSS before update 3.5.3:

.site-image {width:auto;}

CSS after update 3.5.3:

.new-site-image {width:100%;}

I solved the problem with the custom CSS:
`.new-site-image {width:auto;}

Please take this into account in the next update.