Rather than placeholders here, it is better to build up a style string as done in other plugins. Ex for below:
```js
       if (typeof style.fillColor !== 'undefined') {
         symbolStyle += 'background-color: ' + style.fillColor + ';';
       } 
//Parse the rest of the options
return  divInfo + (symbolStyle !== '' ? ' style="' + symbolStyle + '">' : '>');

```