Given 1) a scalar containing search terms separated by spaces, 2) a scalar block of text that might contain the terms, and 3) a scalar hex color like #FF0000, this sub will return the block of text with each term highlighted (in HTML, using the bold tag with an inline style) with the color. This sub makes no attempt to escape regex control characters -- have fun. And yes, I'm fully prepared to be informed that this functionality has been available in some widespread module for years...
sub HTMLhighlight {
  my($searchterms,$instr,$color) = @_;
  my (@terms)=split(/\ /,$searchterms);
  foreach $i (0..$#terms) {
    $instr =~ s/(?!<.*)($terms[$i])(?!.*>)/<b style=\"background:$colo
+r\">$1<\/b>/gi;
  }
  return $instr;
}

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In reply to HTMLHighlight by Anonymous Monk

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