Style Changes Not working In Wordpress

[Simon Plant]

Hi I hope someone can give me some pointers.
I’m trying to change some elements using Firebug which I have used before but having problems with at the moment.

The first webpage in question is www.plantphoto.com/images/life
I want to change the menu description titled Portfolio (top right) to Images and remove the share icons that are appearing depute the fact they should only be showing on posts not pages.

I can find the code to change the Portfolio (at least think I have) but despite adding it to the css change section of the site it remains the same.


The other page is http://www.plantphoto.com/motion/

I have a video playing in background which is quite dark.
As a result I need to make this subheading  Stills Based & Traditional Videos . . .Scroll Down To View to white.
This is located on the  nicescroll-rails overlay.
Again this is causing problems as I can’t seem to locate the code and know where to alter it.
Hope someone can help.
Cheers Simon