Create 404 not found page for SITE (#211)

* feat: create branded not found page

* fix: wrap link over button and change color to primary

src/app/not-found.tsx

@@ -0,0 +1,98 @@
+'use client'
+
+import palette from '@/styles/palette'
+import { lightTheme } from '@/styles/lightTheme'
+import { Box, Button, ButtonGroup, Container, ThemeProvider, Typography, Fade } from '@mui/material'
+import React, { useEffect, useState } from 'react'
+import { Inter } from 'next/font/google'
+import Image from 'next/image'
+import Link from 'next/link'
+import ONCLogo from '@public/shared/LogoBackgroundImage.png'
+
+// Load the Inter font
+const inter = Inter({ subsets: ['latin'] })
+
+export default function NotFound() {
+  const [isClient, setIsClient] = useState(false)
+
+  useEffect(() => {
+    setIsClient(true)
+  }, [])
+
+  if (!isClient) {
+    return null
+  }
+
+  return (
+    <>
+      <Box height={'90vh'} sx={{ position: 'relative' }}>
+        <Image
+          style={{
+            backgroundSize: 'fit',
+            backgroundRepeat: 'no-repeat',
+            background: `linear-gradient(to bottom right, ${palette.greyLight} 0%, ${palette.grey} 75%)`, // Gradient with percentage stops
+            top: 0,
+            left: 0,
+            position: 'absolute',
+            zIndex: -1,
+            overflowX: 'clip',
+            width: '100%',
+            height: '100%',
+            objectFit: 'scale-down',
+            objectPosition: 'right',
+          }}
+          src={ONCLogo}
+          alt="ONC Logo"
+          loading="lazy"
+        />
+        <Container maxWidth="lg">
+          <ThemeProvider theme={lightTheme}>
+            <Box
+              position={'fixed'}
+              top={164}
+              color={palette.primary}
+              fontFamily={inter.style.fontFamily}
+              textAlign="left"
+            >
+              <Box>
+                <Typography variant="h1" fontSize={'3em'} fontWeight={600}>
+                  Page Not Found
+                </Typography>
+                <Typography gutterBottom variant="body1">
+                  We ran into a problem.
+                </Typography>
+              </Box>
+              <Fade in={true} timeout={400}>
+                <Box>
+                  <Typography sx={{ mt: 4 }} variant="h4">
+                    Here’s some tips to help you out.
+                  </Typography>
+                  <ul>
+                    <li>Try reloading the page.</li>
+                    <li>Use the navigation on the left-hand side to move to a different page.</li>
+                    <li>If the error still occurs, please contact us.</li>
+                  </ul>
+                </Box>
+              </Fade>
+              <Fade in={true} timeout={500}>
+                <ButtonGroup color="primary" sx={{ mt: 8, color: palette.primary }}>
+                  <Button color="primary" onClick={() => window.location.reload()} variant="outlined">
+                    Reload Page
+                  </Button>
+                  <Link href="https://site.healthit.gov/" passHref>
+                    <Button variant="outlined" color="primary" component="a">
+                      Go to Home Page
+                    </Button>
+                  </Link>
+                  <Button color="primary" href="mailto:edge-test-tool@googlegroups.com" variant="outlined">
+                    Contact Us
+                  </Button>
+                </ButtonGroup>
+              </Fade>
+            </Box>
+          </ThemeProvider>
+        </Container>
+      </Box>
+    </>
+  )
+}