.has-submenu {
        position: relative;
    }

    .sub-dropdown {
        display: none;
        position: absolute;
        left: 100%;
        top: 0;
        min-width: 200px;
        margin: 0;
        padding: 0;
        background: white;
    }
.has-submenu > a::after {
    content: ">>";
    float: right;
    font-size: 18px;
}
    .has-submenu:hover .sub-dropdown {
        display: block;
    }