Darker free events in dark mode

Thank you for making great progress on Morgen. The user experience is very good. One suggestion: I think equating Free with Transparent is a poor design. Calendar items should never be transparent. It would result in a sea of symbolic characters without solid color blocks to demarcate them. The color, contrasted with the background, is an important clue to me as to which calendar an item pertains to. HALF transparent might be acceptable, but fully transparent is undesirable. So I am in the habit of making all items "Busy" on creation just to avoid transparent items.