In the Revit.ini file, settings in the [Colors] section define the colors used in various areas of the software.
This setting corresponds to the Alert color that you can specify on the Graphics tab of the Options dialog. This color is used to highlight elements related to a warning or an error.
This setting corresponds to the Selection color that you can specify on the Graphics tab of the Options dialog. This color is used to display selected elements in the drawing area.
This setting corresponds to the Pre-selection color that you can specify on the Graphics tab of the Options dialog. This color is used to display an element when you move the cursor over it in the drawing area, before you click to select it.
[Colors] BackgroundColor=16777215 HiliteColor=12401408 PreHiliteColor=12401408 ErrorColor=33023 CustomColor1=000000 CustomColor2=0000ff CustomColor3=00ffff CustomColor4=00ff00 CustomColor5=ffff00 CustomColor6=ff0000 CustomColor7=ff00ff CustomColor8=13f9e1 CustomColor9=d3adc0 CustomColor10=3abfe0 CustomColor11=8afdcf CustomColor12=7c8d98 CustomColor13=155bc6 CustomColor14=858585 CustomColor15=121eaf CustomColor16=7e4774