Can I create a formatting rule that ONLY applies during the Evening? (e.g. after 6PM)

[John . Smith]

Hello 

I want to mark up tasks that I intend to execute during in the evenings as follows:

A) During the day (i.e. before 6PM)
==> they are visible in the To-Do list, but are visually 'knocked back' (i.e. made to be grey text)

B) During then evenings (i.e. after 6PM) 
==> they are marked up with a stronger colour (e.g. made to be bold black text)

Is this possible in MLO?

PROGRESS SO FAR:

I have marked up the relevant tasks with a context of "@Evenings"

If I go Tools ==> Options ==> Automatic Formatting  ==> Automatic Formatting Rules 

then I can add a new rule whose condition is "Context contains @Evenings" and I can change the formatting accordingly to grey.

This greys out the text during the day.

However I can't work out how to create a formatting rule that only works after 6PM

Cheers

J