Ensure #main always uses 100% width

and not just in in absolute layout mode.

Signed-off-by: Alex Coles <alex@alexbcoles.com>

app/assets/stylesheets/layout/_base.sass

@@ -73,7 +73,8 @@ h4, .wiki h3
   border-bottom: 1px dotted #bbbbbb
 
 #main
-  z-index: 20
+  width:    100%
+  z-index:  20
   overflow: auto
   padding-bottom: $footer-height
 
@@ -81,7 +82,6 @@ h4, .wiki h3
     position: absolute
     top:      55px
     bottom:   0
-    width:    100%
     overflow: hidden
     border:
       bottom: 5px solid $footer-bg-color