Thin grey keyline around cell

Question:
I seem to to suddenly have a very thin keyline around each cell. Can anyone suggest a fix please

Product:
Wix Studio Editor.]

What are you trying to achieve:
Remove a very thin grey keyline around the edge of each cell

What have you already tried:
remove guides

Additional information:
[Include any other pertinent details or information that might be helpful for people to know when trying to answer your question.]