How to color cell in Google spreadsheet by condition?

Question

Google Sheets

In applying "custom formula" in google spreadsheets how to make this condition check current cell value for equality/inequality?
There is a column of dates, you need to color the current cell in a certain color, if this date occurs in the next three days - what condition can you set for the RANGE of cells so that each one looks into the formula and finds a link to itself in the condition there?

Answer 1

Found the answer to the question here:
How to get a link to the current cell in Google Sheets?
In short - make a rule for one cell as usual, and then instead of expanding the range manually - just copy it over the entire row / column, incl. and through "copy frame"