Add Button style

src/atoms/Button.js

 import React from 'react'
+import classes from './Button.local.scss'
 
 const Button = ({ children, type = 'button', disabled, onClick}) => (
   <button
+    className={classes.root}
     type={type}
     disabled={disabled}
     onClick={onClick}>{children}</button>

src/atoms/Button.local.scss

+.root {
+  composes: primary from '../lib/colors.local.scss';
+  text-transform: uppercase;
+  border: none;
+  font-size: inherit;
+  padding: 10px 20px;
+}

src/lib/colors.local.scss

+.primary {
+  background-color: cornflowerblue;
+  color: white;
+}
+