add class to radium code example

Example: add class to radium

import React, { Component } from 'react'
import Radium, { Style } from 'radium'

export default class Home extends Component {
  render () {
    return (
      <div>
        <Style scopeSelector=".TEST p" rules={{ color: '#ffa' }} />
        <div className="TEST">
          <p>1234567</p>
          <p>1234567</p>
          <p>1234567</p>
        </div>
      </div>
    )
  }
}