Get dates for seasonal CSS from iCal calendar file?

Ok, this might take a minute to make sure I’m clear about what I’m wanting to do. It is in two easy parts, but getting the two to work together is what eludes me.

I am putting together a site for my church. I want the CSS to change for the liturgical color for the day. So, seasonal CSS seems to be the only way to accomplish this.

What I would like to do is use a .ics file to get the dates to determine what CSS should be used. Anyone know of a way to do this? EDIT: I should make clear why I can’t just put them in the plugin. Some of our dates change every year, such as Easter and all of the Feasts based off it such as Ascension and Pentecost.

I am using PHP iCalendar (and GVB’s WP-iCal Plugin) to display the calendar for the church (and one of the RSS feed parsers to display the upcoming events in the sidebar). There is an ical parser in there, but I have no idea how to make use of it in the seasonal CSS plugin.

Anyone that has any suggestions about how I might take this task on please pass them along. Even if you don’t have a complete solution, just pass along your ideas.

Thanks,
Berko