Well hi there! Sure, there are two ways to do this.
1. If you want each entries' color to be different, you can put HTML tags right into the description itself. You could put something like this:
< font style='color:#ff0000' > this is the description < /font >
2. If you want EVERY entries' color to be different, you can change the code rather than adding this style to each entry...
document.getElementById("Journal").outerHTML = '< div id=journal >< br >' + ActiveArray[current].DatVal + '< p style="text-align:justify; text-indent:25px" >' + ActiveArray[current].TxtVal + '< /div >';
(where it says < div id-journal > add in that font tag afterwards.