HIGHLIGHT colour_data
NOHIGHLIGHT

See COLO(U)R for details of what colour_data should be. See also the BANNER command. The NOHIGHLIGHT command (which does not require a parameter) is a shortcut for HIGHLIGHT WHITE or its equivalents - it resets the background colour back to white, which is the default (since paper is normally white!).

Examples:

HIGHLIGHT LIGHT_RED
HIGHLIGHT #FF0000
HIGHLIGHT 100%, 0%, 0%