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Click on edit
Step 4: Click edit
The The box can be edited with CSS code, a basic function to change the background color is by writing in the case of style a code. See the Image image below.
It is likely that you don't have CSS knowledge, in that case here are some links that are helpfyl for copying the code.
Div box - https://www.w3schools.com/css/css_boxmodel.asp
Colors - https://www.w3schools.com/css/css_colors.asp
Backgrounds - https://www.w3schools.com/css/css_background.asp
Step 5: Click save or preview
With the given style the dic div box will look something like this.
