One TRUE value is treated as 1, which is why two TRUE values sum up to 2. You just need to check your cells against equating to 2. Please see a picture below; of range A1:A5 only A2 gets colored since only B2+C2 result in 2.

Set conditional formatting to use a checkbox to change row color individually throughout the sheet - Google Docs Editors Community
checkbox - Google Sheets - Change row color once multiple boxes are checked - Stack Overflow
conditional formatting - Google Sheets: Change text color of multiple cells if checkbox is checked? - Web Applications Stack Exchange
Changing a Cell's Color based on a Checkbox Condition
I am using google sheets to create a calendar with a checkbox on each day. I am doing the calendar by hand and adding a checkbox. However when I select all the cell where I want the checkbox, I click Insert > Checkbox, it makes some of them with black borders (and filled black when checked) or with a colored border and filled with the color of the cell when checked. I would like them all the have the gray border, but I can't figure out where to change that. Thanks for the help!:)
Here's the link to the spread sheet. You can see that most Sundays have the different format, starting from January.
So I've been trying to make something in Google Sheets for a while now, I have 2 checkboxes, one black and one white, as well as some text on another cell. I want to make the black one white if the white one is checked, same thing with the text on another cell. I tried searching for a solution but nothing I found worked. Any help would be greatly appreciated!

