Make the blip graph more usable by people with red/green colour blindness

The blip graph at https://control.aa.net.uk/blip.cgi tells me that "Green is login" and "Red is logout".

Like ~10% of the male population I'm red/green colour blind. If I stare at the graph closely, I can just about detect that the grass above the axis is a very slightly different colour from the grass below the axis - but I can't work out which is red and which is green.

I don't know if it's important which are logins and which are logouts - I guess it is important, otherwise you wouldn't have made the decision to show them in different colours. But it would be more helpful if there was a way to distinguish between logins and logouts if one doesn't have full colour vision.

Some suggestions: use a different pair of colours; change the text to state "above the axis is logon, below the axis is logout" (or the other way round, as I can't tell...); label the graph with "Logins" and "Logout"