anchor.diff:    test('should handle media rules', () {
       var css = '@media screen and (max-width:800px) {div {font-size:50px;}}';
       var expected =
  -        '@media screen AND (max-width:800px){div.$content {font-size:50px;}}';
  +        '@media screen AND (max-width:800px) {div.$content {font-size:50px;}}';
       shimAndExpect(css, expected);
     });
   
  
positive.code:   });
  
    test('should handle media rules with simple rules', () {
      var css = '@media screen and (max-width: 800px)'
          '{div {font-size: 50px;}} div {}';
      var expected = '@media screen AND (max-width:800px)'
          '{div.$content {font-size:50px;}} div.$content {}';
      shimAndExpect(css, expected);
    });
  
    // Check that the browser supports unprefixed CSS animation
    test('should handle keyframes rules', () {
      var css = '@keyframes foo{0%{transform:translate(-50%) scaleX(0);}}';
      shimAndExpect(css, css);
    });
  
    test('should handle -webkit-keyframes rules', () {
      var css = '@-webkit-keyframes foo'
          '{0%{-webkit-transform:translate(-50%) scaleX(0);}}';
      shimAndExpect(css, css);
    });
  
  
negative.code: 
    test('should shim rules after @import', () {
      var css = '@import url("a"); div {}';
      shimAndExpect(css, '@import url("a");div.$content {}');
    });
  
    test('should leave calc() unchanged', () {
  