PaperPanel.js

import React, { Component } from 'react';
import Paper from 'material-ui/Paper';

const panelStyle = {
  width: '400px',
  marginLeft:  '42%',
  marginRight: '50%',
} 

class PaperPanel extends Component {
  render() {
    return (
      <Paper style={panelStyle} zDepth={2}>
        {this.props.children}
      </Paper>
    )
  }
}

export default PaperPanel;