fix footer better

src/components/App.js

@@ -4,7 +4,7 @@ import Main from './Main';
 import React from 'react';
 
 const App = () => (
-  <div style={{ minHeight: '100%', position: 'relative' }}>
+  <div style={{ minHeight: '100%', position: 'relative', paddingBottom: '3em' }}>
     <header id="header">
       <Header />
     </header>
@@ -13,7 +13,7 @@ const App = () => (
     </main>
     <footer
       id="footer"
-      style={{ width: '100%', bottom: '0' }}
+      style={{ position: 'absolute', width: '100%', bottom: '0' }}
     >
       <Footer />
     </footer>