Edit in JSFiddle

/* SASS variable declaraion Example, $textcolor is a sass variable holds the value 'red'*/
$textcolor:red;
table{
    /*style for table level*/
    thead{
        /*style for thead*/
        tr{
            
             /*style for tr*/
            th{
                 /*SASS variable call example, $textcolor is called which has value 'red used for background*/
                background:$textcolor;
            }
        }
    } 
    
    tbody{
         /*style for tbody*/
        
        tr{
            &.even{
                 /*SASS variable call example, $textcolor is called which has value 'red used for font color*/
                color:$textcolor;
            }
            &.odd{
                 /*style for tr.odd*/
            }
        }
    }
    
    
}