diff --git a/css/swc.css b/css/swc.css
index 33de675..d9b58a9 100644
--- a/css/swc.css
+++ b/css/swc.css
@@ -45,6 +45,7 @@ h1 a, h2 a, h3 a, h4 a, h5 a, h6 a {
 .challenge {
     background-color: #CCFFCC;
     border: 5px solid #CCFFCC;
+}
 
 /* Comments in code. */
 .comment {