add Landing page (#7)

src/components/landing/PageSection/PageSection.tsx

@@ -0,0 +1,12 @@
+import React, { FC, PropsWithChildren } from 'react';
+import { StackProps, VStack } from '@chakra-ui/react';
+
+type PageSectionProps = StackProps & PropsWithChildren;
+
+export const PageSection: FC<PageSectionProps> = ({ children, ...restProps }) => {
+  return (
+    <VStack as='section' w='full' px={5} py={5} spacing={6} alignItems='flex-start' {...restProps}>
+      {children}
+    </VStack>
+  );
+};