.il-maincontrols-resize-handle {
    display: none;
    position: absolute;
    top: 0;
    right: 0;
    width: 4px;
    height: 100%;
    cursor: ew-resize;
    background-color: #bcbcbc;
}

.il-layout-page.with-mainbar-slates-engaged {
    .il-maincontrols-resize-handle  {
        display: block;
    }
}

.il-layout-page.with-mainbar-slates-engaged .il-maincontrols-mainbar {
    width: 100%;
}