Add typescript types for patterns

client/layouts/DetailsLayout.tsx

@@ -4,7 +4,11 @@ import { Link } from 'react-router-dom';
 import useDocumentTitle from '../hooks/useDocumentTitle';
 import Layout from './Layout';
 
-const DetailsLayout = ({ title, children }) => {
+interface DetailsLayoutProps {
+    title: string;
+}
+
+const DetailsLayout: React.FC<DetailsLayoutProps> = ({ title, children }) => {
     useDocumentTitle(`CSS Layout ∙ ${title}`);
 
     return (

client/layouts/Footer.tsx

@@ -2,7 +2,7 @@ import React from 'react';
 
 import Heading from '../components/Heading';
 
-const Footer = () => {
+const Footer: React.FC<{}> = () => {
     return (
         <div className="bl br bb b--black-20 flex justify-between br4 br--bottom">
             <div className="br b--black-20" style={{ flex: 1 }}>

client/layouts/Layout.tsx

@@ -2,7 +2,7 @@ import React, { useEffect } from 'react';
 
 import Footer from './Footer';
 
-const Layout = ({ children }) => {
+const Layout: React.FC<{}> = ({ children }) => {
     useEffect(() => {
         window.scrollTo(0, 0);
     }, []);