ssh-edit/blocks/offcanvas-menu/editor.css

.wp-block-srh-offcanvas-menu .hamburger-lines span {
    display: block;
    height: 2px;
    width: 100%;
    background-color: #ffffff;
    margin: 4px 0;
}

.wp-block-srh-offcanvas-menu .menu-text {
    color: #ffffff;
}