Javascript concatenate string and variable

<!DOCTYPE html>
<html>
<head>
</head>
<body>
    <div id="app">
        <h1>Javascript concatenate string and variable</h1>
        <p id="output"></p>
    </div>
    <script>
        window.onload = function () {
            var name = "John";
            var age = 25;
            var profession = "web developer";

var message = `Hello, <span class="highlight">${name}</span>! 
                           You are <span class="highlight">${age}</span> years old 
                           and work as a <span class="highlight">${profession}</span>.`;

// Access the paragraph element with the ID "output" and set its innerHTML to the message
            document.getElementById("output").innerHTML = message;
        }
    </script>

.highlight {
            color: red;
            font-weight: bold;
        }
    </style>
</body>

</html>