vDom_styles.js

function styles(padding){
  return {
    padding: padding + 'px',
    backgroundColor: '#ddd'
  }
}

function Hello(name, styles){
  return ["div", {style:styles}, "Hello " + name]
}

ReactDOM.render(
  React.createElement.apply(
    this, Hello("World", styles(10))
   ),
  document.getElementById('container')
);