.wp-block-button.is-style-fill.header-b-menu a {
    background-color: #011a3e;
    border: 0.10rem solid transparent;
    transition: border-color 0.8s, color 0.8s;
}

.wp-block-button.is-style-fill.header-b-menu a:hover {
    background-color: #011a3e;
    border-color: #ffffff;
    color: #ffffff !important;
}