Sign Color Positioning?

[GrayTheMudkip]

So i was making signs for houses the way i usually do, but when i put the signs facing East and west it shows the proper coloring it shows on http://ess.khhq.net/mc/ but when facing north and south it darkens the color a bit. This is supposed to be White and Lime Green
How it turned out
But even prism shows what color its supposed to be:

[Pri]

*shrug* this is a Mojang client rendering issue.

[GrayTheMudkip]

Okay thanks for the info pri

[blackeyeddog]

Wait how do u edit a sign without breaking it o.O

[GrayTheMudkip]

Wait how do u edit a sign without breaking it o.O

you can't ._.