hiding gridlines in selected cell areas

[Guest]

How do I hide the gridlines in the selected cell area eg. from a1 to c5?

 

[nika]

Select your desired area and colour fill whit

 

[Hank Scorpio]

How do I hide the gridlines in the selected cell area eg. from a1 to c5?

You can't. But what you CAN do is format those cells with a white cell
shading pattern (that is, a white background). That way you won't have
any gridlines showing in the area unless you add borders.