JavaScript: How to Hide / Unhide <div>

Question

I'm trying to avoid using innerHTML because it causes my browser to crash, probably due to the 250 milliseconds refresh rate.

Anyway, I would rather have some content in an hidden <div> and make the <div> visible only if a certain condition is met. What's the best approach to go around this?

Basically, what I'm doing now is..

setInterval(function () {
    if (serverReachable()) {
        .... // lines of code
        .... // lines of code
    var changeIt = document.getElementById('change')
    changeIt.innerHTML = '';
           timeout = setInterval(function(){window.location.href = "Tracker.html";},5000);
        }
    } else {
        clearTimeout(timeout);
        timeout = null;
    var changeIt = document.getElementById('change')
    changeIt.innerHTML = 'offline';
   }
}, 250);

This will crash my browser, because I'm not using innerHTML to print "offline" but a whole <div>. I want to have this <div> hidden, and instead of using innetHTML, to simply unhide if a condition is met (in this case, no internet connection).

Answer 1

Then use CSS to hide and unhide the div. You can do something like this:

    changeIt.style.visibility = 'hidden';

to make the div disappear. And

   changeIt.style.visibility = 'visible';

to show it again.