You've initialized 2 additional variables, but `parseInt` on a string like "auto" _should_ return `NaN` -- a falsy value.
Meaning you can do this:

```javascript
var marginLeft = parseInt(el.css('marginLeft'), 10) || 0,
      marginRight = parseInt(el.css('marginRight'), 10) || 0;
```

You keep line count equal (which is nice) and don't add any new variables.