 <p>LESS might be a perfect solution. Convert the CSS to LESS by add a scope like this</p> <pre><code>#myId{ .ui-datepicker { ... /* width:auto; (in example) */ } } </code></pre> <p>Now convert it back via LESS2CSS to</p> <pre><code>#myId .ui-datepicker{ ... } </code></pre> <p>Regards.</p>