FOLLOW ALONG ALL ADVICE BELOW: lmk if its impossible.

Figma: Color picker shows when the user hovers over a course block: (the button should be ~3px away from the course block, aka 3px gap)

If a course block is at the right-most edge of the grid, the color picker is on the left side of the course block:

The color picker should be aligned to the top of the course name, regardless if the color picker is on the left or right side of the course block, and regardless of the size of the course block (that means the picker would always be at the left-top or right-top side):

When clicked, show the color palette: (the palette should be ~3px below the color picker button, unless the course block is at the bottom edge of the grid) Clicking on a color should not close the palette until either 1) the color picker button is clicked again or 2) the user clicks outside the palette box. This will make it easier for the user to preview the colors.

If you dont get the gist of it, lmk.