ul {
    width: 100%;
    margin: 0 !important;
    padding: 0;
    text-align: right;
    line-height: 45px;
}

ul li {
    list-style: none;
    display: inline-block;
    padding: 15px;
    color: #ffffff;
    text-decoration: none;
    font-size: 15px;
    background: #000;
}

ul li:hover {
    background: #000;
}

ul li:active {
    background: #a0a0a0;
    opacity: 0.5;
}

a.nav {
    color: #ffffff;
    text-decoration: none;
    font-size: 19px;
    text-transform: uppercase;
}

a.nav:hover {
    color: #c72c2f;
    text-decoration: none;
    /* contour du texte
    -webkit-text-stroke: 2px;
    -webkit-text-stroke-color: #fff;
    */
}

a.nav:active {
    color: #fff;
    text-decoration: none; 
}

.toggle{
    width: 100%;
    padding: 10px 20px;
    background: #000000;
    text-align: right;
    box-sizing: border-box;
    color: #fff;
    font-size: 30px;
    display: none;
}



<!--    -->

@media (min-width: 992px) and (max-width: 1199.98px) {
    
    .toggle {
       display: block;
       text-align: right;
       padding: 30px 20px;
        background: #000;
    }
    ul {
        width: 100%;
        display: none;
        text-align: right;
        padding-top: 15px;
    }
    ul li {
        display: block;
        text-align: right;
        background: #000;
    }
    .active {
        display: block;
    }
}



<!--    -->
    
@media (min-width: 768px) and (max-width: 991.98px) {
    .toggle {
       display: block;
       text-align: right;
       padding: 30px 10px;
        background: #000;
    }
    ul {
        width: 100%;
        display: none;
        text-align: right;
    }
    ul li {
        display: block;
        text-align: right;
        background: #000;
    }
    .active {
        display: block;
    }
}


<!--    -->
    
@media (min-width: 576px) and (max-width: 767.98px) {
    .toggle {
       display: block;
       text-align: right;
       padding: 30px 20px;
        background: #000;
    }
    ul {
        width: 100%;
        display: none;
        text-align: right;
    }
    ul li {
        display: block;
        text-align: right;
        background: #000;
    }
    .active {
        display: block;
    }
}



<!--    -->
    
@media (max-width: 575.98px) {
    .toggle {
       display: block;
       text-align: right;
       padding: 20px 10px;
        background: #000;
    }
    ul {
        width: 100%;
        display: none;
        text-align: right;
    }
    ul li {
        display: block;
        text-align: right;
        background: #000;
    }
    .active {
        display: block;
    }
}