anchor.diff:  
             Indeed you can have 2 main CSS classes at the same DOM node. In BEM we call it `mix`:
   
  -          ```
  +          ```html
             <div class="block1 block2"></div>
             ```
   
  
positive.code: 
            First of all the specifity problem appears. In a local modifier case CSS code goes like this:
  
            ```
            .block {
              display: block;
            }
  
negative.code:           from what people usually mean by "global modifiers" as modifiers do not have any sence on they own and are just a set
            of properties to change.
  
            ```html
            <div class="block globalmod"></div>
            ```
  
  