QuickInfo
The Back column in the Style Editor refers to the screen colour upon which text and images are drawn. Double-click to select color from the Windows colour dialog.
Values
Any integer value in the range of 0 (Black) to 16777215 (White)
Hints
In the Style Editor, when you double-click on the "Back" field, you will pull up the windows colour dialog.
You can select one of the predefined colours and then click Ok. DirectRT will enter the appropriate colour code in the "Back" colour column for you. If you need or desire more selection you can choose from the full range of colours available by selecting "Define Custom Color." This will pull up the custom colour dialog window:
In this window you can click anywhere on the colour spectrum to choose a color. If you first click on one of the standard colours (above) this will give you a starting point from which you can adjust. Either way, click "Ok" when you're done to enter the color code. If you think you'll use the colour again you can click, "Add to Custom Colors" so that it will be available for you as a standard "custom" color in the future.
Note that if you like a colour but it's too dark or too light it's easy to adjust this using the slider on the right hand side of the custom colour dialog.