Why when I try to hide my CSS triangle with jQuery by adding a class does it not work?

Question

I want to hide my CSS triangle which is attached to a div using :before , and I came across this solution to implement: https://stackoverflow.com/a/11354393/998117

However, my jQuery is not working:

$(".contact input[type='submit']").click(function(event) {
    event.preventDefault();
    $(".contact .inner").addClass("hidden");
    ...

(Yes, it does get called.)

This is what my CSS/SASS looks like:

.contact {
    background: #3c6ea5;
    color: #fff;
    display: none;
    height: 500px;

    .hidden:before {
            display: none;
        }

    .inner {
        margin: auto;
        padding-top: 20px;
        position: relative;
        width: 400px;

        &:before {
            border: solid;
            border-color: #3c6ea5 transparent;
            border-width: 14px 16px 0 16px;
            bottom: -107px;
            content: "";
            display: block;
            position: absolute;
            right: -50px;
        }

        .hidden:before {
            display: none;
        }
    }
    ...

Why is it not hiding it? What am I doing wrong?

Answer 1

Your Sass is off just a little bit, should be:

.inner {

    &.hidden:before {
        display: none;
    }
}

Notice the & before hidden

Answer 2

Try below code to solve your problem:

.inner { &:before {     
     .hidden & { display:none;}}}