Use the pop-up color palette to select a color from the spectrum of hues, saturation, and brightness. You can also select a grayscale value.
Control-click a color well or click the adjacent down arrow button, then do any of the following:
Click in the top area to select a color from the spectrum of hues, saturation, and lightness.
As you drag in either area, the pointer becomes an eyedropper, the column on the right displays the RGB and HLS values for the sampled colors, and two swatches above the RGB information display the current and sampled colors. As you sample in the spectrum, the selected object in the canvas updates dynamically.
Click in the bottom gradient to select a grayscale value.