The shades of the grades below show how the shade changes as the GREEN color is increased by 8 units for each progression of the grade. Both RED and BLUE have zero units for that color for each progression. Number 30 then has the maximum (255) of GREEN and no RED or BLUE units of those colors. In hexadecimal FF (255) is the highest number used for colors in Web Hex numbers.

The first two numbers are the units in the base 16 (hexadecimal) of the color RED. The next two numbers are the units in the base 16 (hexadecimal) of the color GREEN. The last two numbers are the units in the base 16 (hexadecimal) of the color BLUE.
Beginning at number 31 we show how you lighten the GREEN color. We do that by leaving the GREEN at its maximum of FF (255) and progressively adding 23 equal amount of both RED and BLUE. As each of the RED and BLUE colors approach the maximum of FF (255) the shade gets closer to white.