Update ssSearch.css

Fix missing CSS property.

Author: martindholmes

css/ssSearch.css

@@ -186,6 +186,7 @@ a.fidLink{
 div#ssPoweredBy{
     font-size: 0.75rem;
     display: flex;
+    flex-direction: column;
     align-items: center;
     justify-content: center;
     margin: 0.5rem;