I hope someone will be able to help with this one.
When viewing my site, http://perfect.hatchmedia.ie, in Chrome and Firefox, I notice a significant difference on the top of the Portfolio page. On Chrome, the first post is in line with the filter icons to the left, however, in Firefox, there is a noticeable gap from the top of the content wrapper to the first portfolio item.
I have been looking at this for a long time now and hope a new set of eyes will be able to help!
this is not a theme issue; the new “swoosh” element you’ve introduced (the one containing the curved line below the menu) shifts the portfolio container down in Firefox. Please try giving it a -55px bottom margin.