Solução criada com Css-flexbox, grid e responsivo e menu JavaScript

Very good! The only thing missing is the hover state CSS for the navbar links. You can add this with a simple animation in CSS:

&::after {
    content: "";
    position: relative;
    display: inline-block;
    width: 100%;
    height: 2px;
    background-color: $White;
    transform: scale(0);
    transition: transform 0.3s ease-in-out;
    transform-origin: right;
    top: -12px;
}