feat(sidebar): render as button menu for < sm viewports

Preserve as much screen real estate as possible by hiding the sidebar
behind a 25% transparent menu button for viewports smaller than `sm`

- For < sm viewports,
  - ensure page layouts are at absolute top left
  - move AppNavbar title to centre

- Use breakpoint responsive values to render either a sidebar,
  or a hidden sidebar revealed by an icon button

src/components/AppNavbar.tsx

@@ -23,12 +23,19 @@ export const AppNavbar = (): JSX.Element => {
         justify="space-between"
         align="center"
         px={{ base: '1.5rem', md: '1.8rem', xl: '2rem' }}
+        pl={{ base: `calc(1rem + ${ADMIN_NAVBAR_HEIGHT})`, sm: '1.5rem' }}
         py="0.375rem"
         bg="white"
         borderBottomWidth="1px"
         borderColor="base.divider.medium"
+        transition="padding 0.1s"
       >
-        <Link as={NextLink} href="/home">
+        <Link
+          as={NextLink}
+          href="/home"
+          mx={{ base: 'auto', sm: 0 }}
+          transition="margin 0.1s"
+        >
           <Image
             // This component can only be used if this is an application created by OGP.
             src="/assets/restricted-ogp-logo-full.svg"

src/components/DashSidebar.tsx

@@ -1,22 +1,41 @@
-import { Box, Flex } from '@chakra-ui/react'
+import {
+  Box,
+  CloseButton,
+  IconButton,
+  Flex,
+  useBreakpoint,
+} from '@chakra-ui/react'
 import {
   SidebarContainer,
   SidebarItem,
   useIsMobile,
 } from '@opengovsg/design-system-react'
 import Link from 'next/link'
 import { useRouter } from 'next/router'
-import { useMemo } from 'react'
-import { BiFace, BiHomeSmile } from 'react-icons/bi'
+import { useMemo, useState } from 'react'
+import { BiFace, BiHomeSmile, BiMenu } from 'react-icons/bi'
 import { ADMIN_DASHBAR_WIDTHS, ADMIN_NAVBAR_HEIGHT } from '~/constants/layouts'
 import { useMe } from '~/features/me/api'
 import { HOME, PROFILE, SETTINGS_PROFILE } from '~/lib/routes'
 
 export const DashSidebar = () => {
+  const [showWhenSmallMobile, setShowWhenSmallMobile] = useState(false)
   const isMobile = useIsMobile()
   const { me } = useMe()
+  const breakpointValue = useBreakpoint()
   const { pathname, query } = useRouter()
 
+  const mobileButtonProps = {
+    zIndex: 'overlay',
+    colorScheme: 'neutral',
+    border: '0px',
+    borderRight: '1px',
+    boxSize: ADMIN_NAVBAR_HEIGHT,
+    borderRadius: '0px',
+    borderColor: 'base.divider.medium',
+    display: { base: 'inline-flex', sm: 'none' },
+  }
+
   const isProfileActive = useMemo(() => {
     if (pathname === SETTINGS_PROFILE) return true
     if (
@@ -26,19 +45,53 @@ export const DashSidebar = () => {
       return true
   }, [pathname, query.username, me?.username])
 
+  const showText = isMobile && breakpointValue === 'sm'
+
   return (
-    <Box position="relative">
+    <Box
+      position={{ base: 'fixed', sm: 'relative' }}
+      zIndex={{ base: '20', sm: '1' }}
+    >
+      {showWhenSmallMobile ? (
+        <CloseButton
+          {...mobileButtonProps}
+          aria-label="Close sidebar"
+          onClick={() => setShowWhenSmallMobile(false)}
+          bg="slate.100"
+        />
+      ) : (
+        <IconButton
+          {...mobileButtonProps}
+          aria-label="Open sidebar"
+          onClick={() => setShowWhenSmallMobile(true)}
+          bg="white"
+          variant="clear"
+          icon={<BiMenu size="1.25rem" />}
+        />
+      )}
       <Flex
         bg="white"
+        borderTop={showWhenSmallMobile ? '1px solid' : undefined}
         borderRight="1px solid"
         borderColor="base.divider.medium"
         pos="fixed"
         width={ADMIN_DASHBAR_WIDTHS}
         h={`calc(var(--chakra-vh) - ${ADMIN_NAVBAR_HEIGHT})`}
+        opacity={{
+          base: showWhenSmallMobile ? 1 : 0,
+          sm: 1,
+        }}
         flexDir="column"
         justify="space-between"
         zIndex="2"
+        top={ADMIN_NAVBAR_HEIGHT}
+        pt={0}
         pb="0.5rem"
+        w={{ base: showWhenSmallMobile ? '100%' : 0, sm: 'fit-content' }}
+        transition={{
+          base: 'opacity 0.2s, width 0.2s',
+          sm: undefined,
+        }}
       >
         <SidebarContainer size="sm">
           <SidebarItem
@@ -47,21 +100,23 @@ export const DashSidebar = () => {
             href={HOME}
             isActive={pathname === HOME}
             title="Home"
-            px={{ base: '0.75rem', md: '1rem' }}
+            px={{ base: '1.125rem', sm: '0.75rem', md: '1rem' }}
             borderRadius={{ base: 0, md: 'md' }}
+            onClick={() => setShowWhenSmallMobile(false)}
           >
-            {isMobile ? '' : 'Home'}
+            {showText ? '' : 'Home'}
           </SidebarItem>
           <SidebarItem
             icon={BiFace}
             as={Link}
             href={`${PROFILE}/${me?.username}`}
             isActive={isProfileActive}
             title="Profile"
-            px={{ base: '0.75rem', md: '1rem' }}
+            px={{ base: '1.125rem', sm: '0.75rem', md: '1rem' }}
             borderRadius={{ base: 0, md: 'md' }}
+            onClick={() => setShowWhenSmallMobile(false)}
           >
-            {isMobile ? '' : 'Profile'}
+            {showText ? '' : 'Profile'}
           </SidebarItem>
         </SidebarContainer>
       </Flex>

src/pages/home.tsx

@@ -1,15 +1,25 @@
 import { Box, Flex } from '@chakra-ui/react'
 import { SkeletonPostList } from '~/components/SkeletonPostList'
 import Suspense from '~/components/Suspense'
-import { APP_GRID_COLUMN, APP_GRID_TEMPLATE_COLUMN } from '~/constants/layouts'
+import {
+  ADMIN_NAVBAR_HEIGHT,
+  APP_GRID_COLUMN,
+  APP_GRID_TEMPLATE_COLUMN,
+} from '~/constants/layouts'
 import { NewPostBanner, PostList } from '~/features/home/components'
 import { type NextPageWithLayout } from '~/lib/types'
 import { AppGrid } from '~/templates/AppGrid'
 import { AdminLayout } from '~/templates/layouts/AdminLayout'
 
 const Home: NextPageWithLayout = () => {
   return (
-    <Flex w="100%" flexDir="column">
+    <Flex
+      w="100%"
+      flexDir="column"
+      position={{ base: 'absolute', sm: 'inherit' }}
+      left={{ base: 0, sm: undefined }}
+      minH={`calc(100% - ${ADMIN_NAVBAR_HEIGHT})`}
+    >
       <AppGrid
         templateColumns={APP_GRID_TEMPLATE_COLUMN}
         px={{ base: '1rem', lg: 0 }}

src/templates/layouts/ProfileLayout.tsx

@@ -12,7 +12,12 @@ const _ProfileLayout: NextPageWithLayout['getLayout'] = (page) => {
   const username = String(query.username)
 
   return (
-    <Flex w="100%" flexDir="column">
+    <Flex
+      w="100%"
+      flexDir="column"
+      position={{ base: 'absolute', sm: 'inherit' }}
+      left={{ base: 0, sm: undefined }}
+    >
       <AppGrid
         templateColumns={APP_GRID_TEMPLATE_COLUMN}
         bg="base.canvas.brand-subtle"
@@ -33,7 +38,9 @@ const _ProfileLayout: NextPageWithLayout['getLayout'] = (page) => {
           <ProfileTabs username={username} />
         </Box>
         <Divider gridColumn={{ base: '1/5', md: '1/12' }} h="1px" />
-        <Box gridColumn={APP_GRID_COLUMN}>{page}</Box>
+        <Box gridColumn={APP_GRID_COLUMN} minH="100%">
+          {page}
+        </Box>
       </AppGrid>
     </Flex>
   )