diff --git a/grid.css b/grid.css
index d574955..8073f45 100644
--- a/grid.css
+++ b/grid.css
@@ -435,6 +435,7 @@ img {
   .column.one-fourth {
     margin: 2em 0 0 0;
     width: 100%;
+    float: none;
   }
 
   .column:first-child { margin-top: 0; }