If not, which versions of Safari and IE are you using?
Where is the font-weight value applied? And how is it written, exactly? Is it cross-browser compatible? What have you tried (ruled out as possible causes)?
Or was it some other text that I was supposed to be looking at?
It may indeed be your own system setup that is different in some way.
Post some screenshots of the problem and list which browsers and versions you are having trouble with. Fonts always look different between the PC and mac anyway.
For me the difference was there, but only subtle, not enough to cause concern, remember, “normal” visitors will only be looking at it in just one browser and would be none the wiser (nor even care) that another browser displays a subtle difference.
The text I viewed used “Roboto” font and had fallbacks, weight set to 400.
I saw something similar in IE because I had a bit of zoom on in that browser.
I have sorted most of the css issues with the body text now.
I still have some kinks to iron out with the responsiveness of the site in between desktop and tablet view…
You probably need to switch to “hamburger” sooner, before the menu clashes with the logo and the logo gets bigger. Or allow the menu to wrap first if that’s preferred.