Gatsby setup for API docs

site/components/layout.js

@@ -0,0 +1,8 @@
+import styled from '@emotion/styled';
+import {baseSpacingPx} from '../util/typography';
+
+export const Page = styled.div({
+  display: 'flex',
+  flexDirection: 'column',
+  margin: 2 * baseSpacingPx
+});