fix popper header (#233)

src/components/Nav/Header/Header.tsx

@@ -205,7 +205,7 @@ export const Header = (props: Props) => {
                   onMouseOver={() => toggleSubnavigation(true, setIsTopicsVisible)}
                   onMouseOut={() => hideSubnavigation}
                   routeName="topics"
-                  active={isFeedVisible()}
+                  active={isTopicsVisible()}
                   body={t('topics')}
                 />
                 <Link

src/styles/app.scss

@@ -980,6 +980,7 @@ details {
 
 iframe {
   border: none;
+  color: rgba(255, 255, 255, 0);
 }
 
 .lead {
@@ -990,4 +991,5 @@ iframe {
 
 .cursorPointer {
   cursor: pointer;
+  color: rgba(255, 255, 255, 0);
 }