Update sidebar popup to new width

jet/static/jet/css/_sidebar.scss

@@ -421,8 +421,10 @@
     -webkit-overflow-scrolling: touch;
 
     @include for-mobile {
-      min-width: 280px;
-      max-width: 360px;
+      width: 360px;
+    }
+
+    @include for-phone {
       width: 80%;
     }