To customize a background color
Open Display in Control Panel.
On the Desktop tab, click Color to display the available colors.
In the Color dialog box, click anywhere in the color matrix on the right.
Drag the pointer in the color matrix to the right or left to change hue Drag the pointer up or down to change color saturation Drag the slider at the right of the matrix to change the luminosity
Once you have defined the color you want, click Add to Custom Colors and then click OK.
To open Display, click Start, click Control Panel, click Appearance and Themes, and then click Display.
To create multiple custom colors, click a color under Basic colors before you define your custom color. Once you have defined the new color, click Add to Custom Colors to add the new color.