Color in A1 to define color used by Conditional Formatting?

Hello everybody,

Last few days I've been trying to figure out if it's at all possible to change the color defined in Conditional Formatting based on the color or value of another cell.
Learned tons.. but still not what I was trying to achieve. Hoping that someone here could shed some light on this for me.

To explain what I'm trying to achieve in a bit more detail:

I'm currently working on an adapted ideal-week-calendar in excel (based on https://michaelhyatt.com/ideal-week.html).
Looking to implement quite some features to this document, but I'm slightly stuck on the color-coding part at this moment.

On worksheet_Settings I defined a list (list_A) that contains multiple words that are used to color in matching words in the calendar on worksheet_Calendar.
Applied the following formula to the conditional formatting to get this to work =ISNUMBER(MATCH(Calendar!B2;list_A;0))

However, I'd like to be able to fill e.g. A1 with 'yellow' wich in turn fills all cells containing a word from list_A with 'yellow'.
Changing A1 to blue, pink or any color in turn changes the conditional formatting applied to the color as defined in A1.
Color picking could be through a drop-down menu limiting the color choices slightly OR Just having a blank cell where a color can be filled into

Does anyone have an idea on how to achieve something like this?
Any help is majorly appreciated.

Regards,
Tom

Probably VBA

I tend to agree that a solution as flexible as what you describe would probably require VBA. I might be able to give some guidance.

Your file does not match what you described (no sheet Calendar, but instead Planner; no name list_A, but instead LIST_1, LIST_2, LIST_3; nothing in cell A1). I get the general idea of what you want but it would help for you to manually set up an example of what you want the result to look like.

Excel does not have any built-in function that allows you to query the fill color of a cell, which is why VBA is probably required. If you predefine a fixed list of colors you would want to use, it might be possible to create conditional formatting rules to do this, but you would need at minimum a rule for each color, and maybe a rule for each combination of color and row on sheet Settings. If you ever wanted to add or change a color, it would require updates to the CF rules. A VBA solution could be fully automatic.

Let me know where you want to go from here.