I used a tool on your site, that does retrieve all colors used on your page an actually,
i can confirm that the only green color used on your site is the #78f118.
On my firefox i do not register any notable difference in colours with my eyes anyway, so
one likely reason in my opinion is: when you do a lot work with colours, do lots of web design, then
your eyes get oversensitive and the tiniest optical illusion may appear as a huge difference.
The optical illusion in effect on your web site is simply: You use the same green on different type backgrounds
and of course a green on a white/light background appears definitely darker than the same green on
a black/dark background.
Though only to repeat myself: seen first time with neutral eyes I do not notice anything outrageous, so
I would take it easy here ;-))