如何在循环变量的jQuery中应用css？

Hello guys I search alot but find nothing regarding my problem. I have one foreach loop in that i have one anchor tag and that will be changed according to my ifelse condition. Now I want to change color of each if else condition in that. Please help me to do.My code is within jQuery script.

for(var j=0;j<arrayData.length;j++){
  var country = "";
  if(arrayData[j].key=="40"){
    country = "UK";
  }else if(arrayData[j].key=="41"){
    country = "INDIA";
  }else if(arrayData[j].key=="47"){
    country = "POLAND";
  }else{
    country = "GERMANY";
  }
  check+='<a class="btn btn-success" href="<?php echo base_url()?>uploads/'+arrayData[j].value+'">'+country+
                    '</a>|';
}
check +='</td></tr>';

You can just append it on the html string.

for(var j=0;j<arrayData.length;j++){
   var country = "";
   var color = "";
   if(arrayData[j].key=="40"){
       country = "UK";
       color = "red";
   }else if(arrayData[j].key=="41"){
       country = "INDIA";
       color = "orange";
   }else  if(arrayData[j].key=="47"){
       country = "POLAND";
       color = "yellow";
   }else{
        country = "GERMANY";
       color = "green";
   }

   check+='<a class="btn btn-success" style="background-color:' + color  + ';" href="<?php echo base_url()?>uploads/'+arrayData[j].value+'">'+country+
                    '</a>|';
}

 check +='</td></tr>';

Other option: You can also add class to <a> tag.

Like <a class="color-red">

CSS:

.color-red {
   background-color: red;
}