Fix Portal scrolling getting stuck (#4455)

* Fix Portal scrolling getting stuck

* DappCard container flex

* Container height to 100%

js/src/modals/AddDapps/addDapps.css

@@ -30,6 +30,10 @@
 .list {
   margin-bottom: 1.5em;
 
+  &:last-child {
+    margin-bottom: 0;
+  }
+
   .background {
     padding: 0.5em 0;
   }

js/src/ui/Container/container.css

@@ -23,10 +23,11 @@
 
 .compact,
 .padded {
+  background-color: transparent !important;
   border-radius: 0 !important;
+  height: 100%;
   position: relative;
   overflow: auto;
-  background-color: transparent !important;
 }
 
 .compact {

js/src/ui/Portal/portal.css

@@ -50,6 +50,7 @@ $popoverZ: 3600;
   left: 0;
   right: 0;
   opacity: 0.25;
+  z-index: -1;
 }
 
 .overlay {