Sorry to bring this up again, but in the process of making a pull request to Foundation for the sidebar input width bug, I noticed your foundation.css is missing a style declaration that is present in forms.css that may solve the issue:
Line 35 of forms.css
input.expand, textarea.expand { width: 100%; }
Line 41 of forms.css
textarea.locked.expand { max-width: 100%; }
I'm not sure if you left these out intentionally, but this gets rid of the bug in the Foundation framework demo (test.html, although I had to manually add the input field to the sidebar).
Sorry to bring this up again, but in the process of making a pull request to Foundation for the sidebar input width bug, I noticed your foundation.css is missing a style declaration that is present in forms.css that may solve the issue:
Line 35 of forms.css
Line 41 of forms.css
I'm not sure if you left these out intentionally, but this gets rid of the bug in the Foundation framework demo (test.html, although I had to manually add the input field to the sidebar).