Foreground is an integer expression which specifies the color of the characters printed on the display and is, by definition, normally white. The value of Foreground may be zero for black, one for white with underlining or two through seven for white (no underlining). Background is an integer expression which specifies the color of the display background and is, by definition, normally black. The value of Background may be seven for white or zero through six for black.
color 0,7: print "This is reverse video" color 1,0: print "This is underlined" color 7,0: print "This is normal"demonstrates these modes.
In the description above, only values less than eight are discussed. Larger values may be specified; they are divided by eight and the remainder is used. For example, a Foreground value of 25 may be specified and is regarded as a one for underlining.
Specifying white on white or black on black is not an error, but nothing happens.
from The Basmark QuickBASIC Programmer’s Manual by Lawrence Leinweber