"See you this evening!"
That would mean "Do you see this evening?".
The English phrase "see you" (short for "I will see you") is translated to the Dutch farewell "tot ziens" or, if it refers to a specific time, "tot <time>". Literally, this just means "until this evening".
If you look back at what we've previously been taught - or look at the drop downs, See you = Tot Ziens. So why don't I need to say 'Tot ZIENS vanavond'? Is the ziens just assumed, in a form of shorthand?