Styling the accordion

Hi,

I am trying to style the accordion.

I would just like it to have white background, black titles and a simple 1px solid #d4d4d4 border everywhere (I’m attaching a picture so you can see what I want to do).

I’m adding this code to the custom css but it does nothing.
What am I doing wrong?

Thank you!

.vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel.vc_active .vc_tta-panel-heading {
    border-color: 1px solid #d4d4d4;
    background-color: #fff;
}

.vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel .vc_tta-panel-body {
    background-color: #fff;
}

.vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel .vc_tta-panel-body, .vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel .vc_tta-panel-body::after, .vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel .vc_tta-panel-body::before {
    border-color: #d4d4d4;
}

.vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel .vc_tta-panel-title>a {
    color: #000;
}

.vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel .vc_tta-panel-heading {
    border-color: #d4d4d4;
    background-color: #fff;
}

.vc_tta-color-grey.vc_tta-style-classic .vc_tta-panel.vc_active .vc_tta-panel-title>a {
    color: #000;
}