Can someone please help me to remove the lines in between

Hi all,

Could someone please help me figure out how to remove these lines from my chart?

My goal is to overlay this chart on top of another one—similar to how it's done in other parts of the workbook. The base chart is fixed inside a container, and the overlay chart is floating.

What’s the best way to set this up so it doesn’t break or misalign on large monitors or different screen sizes? I tried adding device layouts. It did not work.

Thanks in advance!