diff --git a/css/reset.css b/css/reset.css
index ec950271749e654f8332a2d11b411a9024e39e1e..6e10c45e871c9922a0c8d21218e658bce0aa9063 100644
--- a/css/reset.css
+++ b/css/reset.css
@@ -182,3 +182,18 @@ img.picture{
 footer#bottom{
     font-size:  medium;
 }
+
+/*collapse*/
+.collapse > a{
+    cursor: pointer;
+    display: block;
+}
+.collapse:focus{
+    outline: none;
+}
+.collapse > div{
+    display: none;
+}
+.collapse:focus div{
+    display: block; 
+}