A simple table with inline styling: https://jsfiddle.net/danyaljj/ud5p4yo0/

reactJS_example_changeColor.jsx

var style = {
    backgroundColor: 'red',
}

var Hello = React.createClass({
    render: function() {
        //return <div>Hello {this.props.name}</div>;
        return (
        <table> 
            <tr>
                <th style={style}>Month</th>
                <th>Savings</th>
              </tr>
              <tr>
                <td>January</td>
                <td>$100</td>
              </tr>
              <tr>
                <td>February</td>
                <td>$80</td>
              </tr>
        </table> 
        ); 
    }
});
 
React.render(<Hello name="World" />, document.getElementById('container'));