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window.addEventListener(‘load‘, function() {
     var status = document.getElementById("status");

function updateOnlineStatus(event) {
         var condition = navigator.onLine ? "online" : "offline";
         status.className = condition;
         status.innerHTML = condition.toUpperCase();
     }
     window.addEventListener(‘online‘, updateOnlineStatus);
     window.addEventListener(‘offline‘, updateOnlineStatus);
 });