How do I Verify the CSS Background-Image URL with Javascript

The logic is to check the url of the CSS element’s id(.boot). If the url matches, which it does, then it prints hello world. But it doesn’t do anything and I don’t know why.

Context: There’s a button. I click it. It checks the CSS background url. If the url matches it creates an alert.

CSS:

.boot {
    width: 1000px;
    height: 1000px;
    background-image:url(Videos/printgifstart.GIF);
    background-repeat: no-repeat;
    background-size: 100%;
    background-position: center;
    position: fixed;
    bottom: -150px;
    right: 105px;
    z-index: 100;
}

HTML + Javascript

<div class="Logo2" id="blogo">
<h1></h1>
<div class="MirroredSmiles"></div>
<button id="ticketb" class="ticketb"
    style="height:100px;
        width: 75px;
        position: fixed;
        top: 335px;
        left: 200px;
        opacity: 0%;"
        onclick="tixbPLS">
</button>

    <script>
        var tix = document.getElementsByClassName('ticket');
        var tixb = document.getElementById('ticketb');
        var tixc = document.getElementById('ticketc');
        var sart = document.getElementById('shopdrawing');
        var sart2 = document.getElementById('shopdrawing2');
        var sart3 = document.getElementById('shopdrawing3');
        var sbakdo = document.getElementById('backdoor2');

        tixb.addEventListener('click', tixbPLS);

        function tixbPLS() {
            if (document.getElementById('boot').style.backgroundImage = url('Videos/printgifstart.GIF'))
            {
                alert("hello! world!");
            }
        }
    </script>
</div>

I looked online and the issue seemed to lean into a syntax error but I have played with the syntax for hours and it cannot print hello world.

I thought maybe this only works with images and even with an image still no luck.

I tried "=" or "==" still no luck.

I thought maybe somehwere in the code something else is the issue. So instead of the original if statement. I did a math equation type if statement and the alert worked perfectly.

So everything else is fine except for that singular if line.