Extend Support & Forum threads content max-width to 1160px to match developer & documentation

[dufresnesteven]

Support thread page content is restricted to 960px which is based on older browser specs and makes some information hard to read. The time string in the forum table for example.

The rest of our documentation and developer-related themes use 1160px as the default content width. We should do that to the support forums for an immediate upgrade to legibility and would bring a more consistent look and feel.

Changes:

• Update it for the content.
• Update it for the sub-navigation.
  • I would also like to see us apply the new styles to the sub nav similar to what we have done to the profiles page via https://meta.trac.wordpress.org/ticket/7175. I can open a new ticket for that if necessary.
• Reduce the width of the sidebar is it will be longer than necessary.

[renyot]

I think this is a good enhancement and is more visually appealing IMO.

I did a quick test with width: 1060px, here is the screenshot:

And here's reducing the width of the sidebar: (content:70%. sidebar:25%)

[adamwood]

The content width of the new theme is 1160px