Well, I tried there first but it didn’t override the plug-in css.
.ics-calendar-month-grid td,.ics-calendar-month-grid th
{
font-size: "100%"
}
I edited the style.min.cs and changed the font-size from 70% to 100% which was much more readable.
.ics-calendar-month-grid td,.ics-calendar-month-grid th
