Image quality in gallery section

Hi could anyone help me with image quality in gallery section ? 

Images are blurred, without sharpness as per screenshot attached below (blurred) when I zoom in to 150% and then zoom out images appear as they should, sharp and in good quality (sharp) 

Do you know CSS code that will show all images in original resolution and original quality from the beginning ? 

It is extremely annoying since I wanna showcase my pics in best possible resolution and squares pace reduces their quality automatically for no reason. 

And yes Images are uploaded in sizes recommended by square space. 

Previously I also used square space but different template and I had no issues like this so Im guessing it may have something to do with responsive design but Im no expert. 

I would really appreciate someone's help.