I would like to add to my image a layer with colour and set blend mode, for example multiply to 50% of all image width. Like that:

I know how to create that to full image, by how to create on 50% of image width?
Here is example on full image
[https://codepen.io/Matteokr/pen/PyJwKB][2]
One way to achieve that is to use background-blend-mode like this: