Updates to use dynamic/responsive styles on web (#1351)

* Move most responsive queries to the hook

* Fix invalid CSS value

* Fixes to tablet render of post thread

* Fix overflow issues on web

* Fix search header on tablet

* Fix QP margin in web composer

* Fix: only apply double gutter once to flatlist (close #1368)

* Fix styles on discover feeds header

* Fix double discover links in multifeed

src/view/com/auth/onboarding/WelcomeDesktop.tsx

@@ -16,9 +16,7 @@ type Props = {
 
 export const WelcomeDesktop = observer(({next}: Props) => {
   const pal = usePalette('default')
-  const horizontal = useMediaQuery({
-    query: '(min-width: 1230px)',
-  })
+  const horizontal = useMediaQuery({minWidth: 1300})
   const title = (
     <>
       <Text

src/view/com/auth/onboarding/WelcomeMobile.tsx

@@ -7,7 +7,6 @@ import {FontAwesomeIcon} from '@fortawesome/react-native-fontawesome'
 import {Button} from 'view/com/util/forms/Button'
 import {observer} from 'mobx-react-lite'
 import {ViewHeader} from 'view/com/util/ViewHeader'
-import {isDesktopWeb} from 'platform/detection'
 
 type Props = {
   next: () => void
@@ -95,7 +94,7 @@ export const WelcomeMobile = observer(({next, skip}: Props) => {
 const styles = StyleSheet.create({
   container: {
     flex: 1,
-    marginBottom: isDesktopWeb ? 30 : 60,
+    marginBottom: 60,
     marginHorizontal: 16,
     justifyContent: 'space-between',
   },