How to create a grid from random generated numbers between min and max values?

I'm trying to draw a grid representing random generated integers between (-100-100) (Each cell / square corresponds to an integer). 100 corresponding to the hexadecimal value #FF0000 (red) and -100 corresponding to the hexadecimal value #00FF00 (green), then assigning a color to each cell between the two initial colors according to the value of the integer it represents. An example like this one: