Changes

.dayMon{color:#c44a2f !important;}

Example 2: Set the background color for the weekday heading of Monday ('Mon')

.dayMon{background-color:#c44a2f !important;}

Example 3: Set the font color for all the dates that fall on a Saturday

.daysat {color:#c44a2f !important;}

Example 4: Add a border around all the dates that fall on a Sunday