How to Format Cell Borders and Background Colors in Google Sheets
You can spice up your spreadsheets a bit by adding borders and background colors to cells.
A menu of border options appears. Here, you can select where the borders appear around the outside of the selection, or cell borders within the selection.
A border appears around the selected cell(s).
You can also change the border style, including the color and thickness.
The Borders menu is still displayed, and we can see the options to customize the border color and style.
The border is updated, based on the changes you made to it.
You can also change the background color of a cell.
The cells are now filled with a background color.