Restore Cambridge logo to footer on Firefox

On other browsers this was using the max width on screen sizes >~290px anyway.

Author: axlewin

src/scss/phy/footer.scss

@@ -38,6 +38,5 @@ footer {
 }
 
 .footer-org-logo {
-  width: 100%;
-  max-width: 12rem;
+  width: 12rem;
 }