| | | | |
| | | |red| |
|blue| | |green| |

##</code><code>##

use strict;

while (<DATA>) {
   s/\|\|/\| \|/g;
   print;
}

__DATA__
|||||
||||red||
|blue|||green||

##</code><code>##

| || ||
| || |red| |
|blue| ||green| |