diff --git a/static/c4.css b/static/c4.css
index a74dc49..3293b31 100644
--- a/static/c4.css
+++ b/static/c4.css
@@ -27,12 +27,12 @@ h1, h1 a  {
     font-size: smaller;
 }
 
-.btn.green {
+.btn.primary {
     color: #020;
     background-color: #6f3;
 }
 
-.btn.green:hover ,.btn.green:focus {
+.btn.primary:hover ,.btn.primary:focus {
     background-color: #3f0;
 }