I exactly don't know how i sometime did it but it happens sometime and sometime not

Suppose i have a paragrah and i want add the background color to that paragraph.

Google docs adds the background color 2 way

1)One way is that it selects the text only and adds the background color to text characters only 2)The other way is it makes the whole paragraph a block and adds the background color to that block. i.e the background color fill the whole box like div box with background color.

I don't know to try the second way