Add buttons for basic mobile support

src/Provider.js

@@ -1,6 +1,7 @@
 import React from 'react'
 import styled from 'styled-components'
 import Dots from './Dots'
+import { dec, inc } from './index'
 
 const Bottom = styled.div([], {
   position: 'fixed',
@@ -9,6 +10,24 @@ const Bottom = styled.div([], {
   bottom: 0,
 })
 
+const Button = styled.div([], {
+  cursor: 'pointer',
+  width: '64px',
+  height: '100vh'
+})
+const Previous = styled(Button)([], {
+  position: 'fixed',
+  top: 0,
+  left: 0,
+  bottom: 0,
+})
+const Next = styled(Button)([], {
+  position: 'fixed',
+  top: 0,
+  right: 0,
+  bottom: 0,
+})
+
 export default class Provider extends React.Component {
   render () {
     const {
@@ -32,6 +51,20 @@ export default class Provider extends React.Component {
             }}
           />
         </Bottom>
+        <Previous
+          role='button'
+          title='Previous Slide'
+          onClick={e => {
+            update(dec)
+          }}
+        />
+        <Next
+          role='button'
+          title='Next Slide'
+          onClick={e => {
+            update(inc)
+          }}
+        />
       </React.Fragment>
     )
   }