One question I see currently showing up on the forum is to have different header colours, but most of the times since the conditional formatting is only applied to values people tend to say it's not possible.
As refer conditional formatting cannot be applied to a column header however you there are alowed to:
Apply the same format of the column values to the header Apply conditional formatting to the values (text and/or background) Based on this two things we can make a workaround:
Instead of using a column with categories create a measure per each column we want to customize:
In my case I have 3 categories A, B, C that I want to have different colours Create the following measures:
CAT A = CALCULATE(SUM(Table1[Value]);Table1[Cat] = "A")
CAT B = CALCULATE(SUM(Table1[Value]);Table1[Cat] = "B")
CAT C = CALCULATE(SUM(Table1[Value]);Table1[Cat] = "C")
Place the measures in the columns of your matrix or table Go to the options of the table/matrix Field Formatting Choose each one of the measures and make the backgroung and letter the colour you want
In my example A = Green, B = Yellow, C = Red and letter for all of the white For each one click the option Apply to header:
Now add for each measure add conditional formatting for background and colour
In my example for all of them you have black text and white background
Be sure to choose diverging and both color the same
As you can see you have headers with different colours and the values of the tables are the same.
You can also use the other conditional formatting options as color scale or field value just be sure to add one line for the "normal" values that are to be in black colour.
For the Sub column the steps are exactly the same if you are refering to a table visual however if you refer to a Matrix visual since the SUB is on the Rows you just need to format the Column header with the blue colour
So although the Condittional formatting is not actually on the headers it looks like it is.