I ended up finding the answer to this question. It took me several hours to figure out, so I thought I'd post it here for future Splunkers.
I added some custom visualizations in a Splunk dashboard. I print these dashboards to a PDF and want to preserve the color. I was trying to figure out why my charts did not print out in color, but other Splunk charts did. It turns out that it has to do with the Splunk CSS. It has a print configuration like the following:
@media print {
.visualization-controls {
display: none !important;
}
}
If the element doesn't contain the "!important" property, the formatting is removed when printing.
So when setting the color of my objects, I had to add "!important", like the following:
color: darkred!important
Otherwise, just doing "color: darkred" will not pass through the color when printing.