Hey Iris! I summed up comments in Scss (and CSS) for you so you can safely remove them from your current CSS. :)

comments.css

Types of Comments in (S)CSS:

/*
    Standard multi-line comment. 
    This is the most used I'd say. 
    
    Though this is pretty awesome while developing, it should be removed for production.
*/


/*
Normaly, "//" is a single line comment but in CSS it's a a bit tricky. 
In fact, they're not single line at all, they comment out the NEXT block if it's
 not in front of a CSS property.
*/
.foo {
   // width: 10em; <-- commented out only width: 10em
   height: 50em;
}

// commented out the NEXT rule - so it's .bar {} which is commented out
.bar {
    height:10em;
}

/*
    The Special COMPASS Comment.
    When you set line_comments = false in your config.rb it will remove all comments
    expect special declared comment with a "!" after the first /*
*/ 

Example of Special Compass Comments:

/*!
    This comment will stay in the compiled css - useful when developing for WordPress. ;) 
    All other comments will be removed.
*/

So simply put all your WordPress Theme Description Stuff between /*! */ instead of /**/