highlight other cells when click/hoover/check certain cell

I have a big amount of data in one excell sheet. Every cell is er certain type of educational goal (8 types). Now i coloured every special goal standard, but things get complicated like this with a lot of coloring. I wonder if it was possible that in a normal situation no cells are highlighted, but if i want to choose a certain educational goal, all the cells will be highlighted in a certain color.

I have an example attached. The first column has the global educational goals, the next columns with the numbers has been highlighted in blue or with an purple line. So i want everything to be regular, if i hoover/click/... on a cell in de first column, the right cells in the other columns turn blue/yellow/...

Thanks in advance

Hans