Juniper Allegro CE Owner's Manual page 75

Use the Appearance tab to change the color scheme of the display
contents (the default is High Contrast White). Windows Standard and
High Contrast Black and are also recommended.
Options such as Eggplant appear as various shades of gray. As you
make an appearance selection, the change is shown on the left side of
the screen, allowing you to view it before you apply your selection.
You can customize the display by clicking on an element shown on
the left, Window Text for example, or selecting it from the pull down
list shown on the lower right. Above the pull down list the default
color for your selection is shown by tapping on the Color button above
the Item drop down box. Tap in the box and a palette with the
available shades of gray appears.
Windows CE Page 4-15