remove unnecessary usage of headerHeight

commafeed-client/src/pages/app/FeedEntriesPage.tsx

@@ -72,7 +72,7 @@ export function FeedEntriesPage(props: FeedEntriesPageProps) {
     if (noSubscriptions) return <NoSubscriptionHelp />
     return (
         // add some room at the bottom of the page in order to be able to scroll the current entry at the top of the page when expanding
-        <Box mb={viewport.height - Constants.layout.headerHeight - 210}>
+        <Box mb={viewport.height * 0.75}>
             <Group gap="xl">
                 {sourceWebsiteUrl && (
                     <a href={sourceWebsiteUrl} target="_blank" rel="noreferrer" className={classes.sourceWebsiteLink}>

commafeed-client/src/pages/app/Layout.tsx

@@ -173,7 +173,7 @@ export default function Layout(props: LayoutProps) {
                         axis="x"
                         defaultPosition={{
                             x: sidebarWidth,
-                            y: Constants.layout.headerHeight,
+                            y: 0,
                         }}
                         bounds={{
                             left: 120,