Might be better to name this jquery-ui-datepicker.less so we don't have the nightmarish scenario of someone adding the contents of another jquery plugin css to the bottom of this in the future?

Is there any way to keep this as a CSS file?  Since this is from a library, it would be bad to edit and, preferable to add modifications on top of it as another file, and having this be a CSS file would help prevent that.  Or could we add a note to the top of the file not to edit it?