Change the color of a led on html

I'm to change the color of led based on whether of internet connection is there or not.
here's what I have done so far:

style.css

.led-green {
  position: relative;
  right: -50% ;
  top: 10%;
  margin: 0 auto;
  width: 24px;
  height: 24px;
  background-color: #ABFF00;

}
.led-red {
  position: relative;
  right: -50% ;
  top: 10%;
  margin: 0 auto;
  width: 24px;
  height: 24px;
  background-color: rgb(255, 0, 0);

}

app.js

 /** Check if internet connection is avaiable */
  var  internetConnection =""
  require('dns').resolve('www.google.com', function(err) {
    if (err) {
       console.log("No internet connection");
       internetConnection ="led-red";
    } else {
       console.log("Connected to internet ");
       internetConnection ="led-green";

    }

    console.log(internetConnection)
  });

I guess this is the part where I got the problem

index.ejs

  <div class="<%=internetConnection%>"> </div>

my hope was that by starting the app the division would be set like :

<div class ="led-green"> </div> 

or

<div class ="led-red"> </div> 

any idea how may I solve this?

thanks in advance !

Update

I'm the variable in the render function as follows :

.......................
 res.render('index', {
.....
internetConnection:internetConnection,
...............
}

UPDATE

the problem isn't the rendering. the issue is that the html page doens't work when I define div as followed :

<div class="<=%internetconnection>"> <div>

any idea how to solve this ?
thanks again for any hint !

Is it possible that your response is rendered before your app decides whether internet connection is available or not? Seems to me like a problem you are facing because nodejs is asynchronous.

try to put the code you are using to send response to the client in dns.resolve() callback, like:

 var  internetConnection =""
  require('dns').resolve('www.google.com', function(err) {
    if (err) {
       console.log("No internet connection");
       internetConnection ="led-red";
       ejs.render(errorHTMLString, data, options);
    } else {
       console.log("Connected to internet ");
       internetConnection ="led-green";
       ejs.render(noErrorHTMLString, data, options);
    }

    
  });

Hope this helps.

Please make sure that you call the render() function within the callback of resolve():

  var  internetConnection =""
  require('dns').resolve('www.google.com', function(err) {
    if (err) {
       console.log("No internet connection");
       internetConnection ="led-red";
    } else {
       console.log("Connected to internet ");
       internetConnection ="led-green";

    }

    console.log(internetConnection);
    res.render('index', {
      internetConnection:internetConnection,
    }
  });