chore: add custom overrides examples

_override/App.tsx

@@ -0,0 +1,19 @@
+import * as React from 'react';
+import type { Location } from 'history';
+
+/**
+ * Root wrapper.
+ */
+export function App({ children, location }: React.PropsWithChildren<{ location: Location }>) {
+  return (
+    <>
+      {/* you can add some top-level providers here or anything to wrap whole app */}
+
+      {/* <header style={{background: 'yellow', textAlign: 'center', padding: '20px 0', fontSize: '24px'}}>
+        Header
+      </header> */}
+
+      {children}
+    </>
+  );
+}

_override/Footer.tsx

@@ -0,0 +1,149 @@
+import * as React from 'react';
+import styled from 'styled-components';
+
+import { Box, Flex, Link, FooterProps } from '@redocly/developer-portal/ui';
+
+/**
+ * Custom Navbar. The implementation below is almost identical to our default Footer
+ */
+export default function CustomFooter(props: FooterProps) {
+  // you can use columns/copyright values from props, it comes from siteConfig.yaml
+  // but you can also import it from a separate yaml or json file
+  const { columns, copyrightText } = props.footer;
+  const siteVersion = props.siteVersion;
+
+  const columnsElement = columns.length ? (
+    <FooterColumns
+      justifyContent="center"
+      flexWrap="wrap"
+      flex="1"
+      p={{ xs: '3em 0 1em 0', small: '5.625em 0 3.9375em 0' }}
+    >
+      <Flex
+        justifyContent="center"
+        flexDirection={{ xs: 'column', small: 'row' }}
+        flexWrap={{ small: 'wrap' }}
+        maxWidth={'1200px'}
+        flex={{ small: '1 1 100%' }}
+        px={'20px'}
+      >
+        {columns.map((column, index) => (
+          <Box
+            key={index}
+            textAlign={{ xs: 'center', small: 'left' }}
+            mb={{ xs: '4em', small: '3em', medium: 0 }}
+            flex={{ xs: '0 calc(50% - 20px)', small: '0 calc(33.333% - 20px)', medium: 1 }}
+            mx={10}
+          >
+            <ColumnTitle>{column.group || column.label}</ColumnTitle>
+            <ColumnList>
+              {column.items.map((columnItem, columnItemInex) =>
+                columnItem.type === 'separator' ? (
+                  <FooterSeparator key={columnItem.label + '_' + columnItemInex}>{columnItem.label}</FooterSeparator>
+                ) : (
+                  <ColumnListItem key={columnItemInex}>
+                    <Link to={columnItem.link} target={columnItem.target} external={columnItem.external}>
+                      {columnItem.label}
+                    </Link>
+                  </ColumnListItem>
+                )
+              )}
+            </ColumnList>
+          </Box>
+        ))}
+      </Flex>
+    </FooterColumns>
+  ) : null;
+
+  const infoElement =
+    copyrightText || siteVersion ? (
+      <FooterInfo>
+        <FooterCopyright>
+          {copyrightText} {siteVersion ? `| ${siteVersion}` : null}
+        </FooterCopyright>
+      </FooterInfo>
+    ) : null;
+
+  return (
+    <FooterWrapper>
+      {columnsElement}
+      {infoElement}
+    </FooterWrapper>
+  );
+}
+
+const FooterColumns = styled(Flex)`
+  background-color: ${({ theme }) => theme.colors.footer.main};
+  color: ${({ theme }) => theme.colors.footer.contrastText};
+  font-family: ${({ theme }) => theme.typography.headings.fontFamily};
+
+  a,
+  a:hover {
+    color: ${({ theme }) => theme.colors.footer.contrastText};
+  }
+`;
+
+// very important for NavWrapper to be a "footer" HTML tag
+const FooterWrapper = styled.footer`
+  font-size: 1rem;
+  flex-shrink: 0;
+  font-family: ${({ theme }) => theme.typography.fontFamily};
+
+  @media print {
+    color: black;
+    ${FooterColumns} {
+      display: none;
+    }
+  }
+`;
+
+export const FooterInfo = styled.section`
+  display: flex;
+  justify-content: center;
+  font-size: 0.875em;
+  padding: 1.5em 3em;
+  font-weight: ${({ theme }) => theme.typography.fontWeightBold};
+  background-color: ${({ theme }) => theme.colors.footer.main};
+  color: ${({ theme }) => theme.colors.footer.contrastText};
+  span {
+    max-width: 1200px;
+  }
+`;
+
+export const ColumnList = styled.ul`
+  margin: 0;
+  padding: 0;
+  list-style: none;
+`;
+
+export const ColumnListItem = styled.li`
+  font-weight: ${({ theme }) => theme.typography.fontWeightBold};
+  padding-bottom: 0.75em;
+  a {
+    color: ${props => props.theme.colors.primary.contrastText};
+    text-decoration: none;
+  }
+`;
+
+export const FooterSeparator = styled.li`
+  opacity: 0.75;
+  margin: 10px 0 5px 0;
+  font-size: 0.75em;
+  text-transform: uppercase;
+  font-family: ${({ theme }) => theme.typography.headings.fontFamily};
+`;
+
+export const FooterCopyright = styled.span`
+  text-align: center;
+`;
+
+export const ColumnTitle = styled.span`
+  display: inline-block;
+  font-weight: ${({ theme }) => theme.typography.fontWeightRegular};
+  margin-bottom: 1.5em;
+  fontfamily: ${({ theme }) => theme.typography.headings.fontFamily};
+
+  @media only screen and (min-width: ${({ theme }) => theme.breakpoints.large}) {
+    margin-bottom: 2.5em;
+  }
+`;