JSFiddle - React, Tailwind, and code Playground

HTML

<section class="MenuHead">
    <nav class="CorpoMenuHead">
        <a href="{$Directory}">Home</a>
        <a href="{$Directory}Empresa">A Empresa</a>
        <a href="{$Directory}Servicos">Serviços</a>
        <a href="{$Directory}Unidades">Unidades</a>
        <a href="{$Directory}Clientes">Clientes</a>
        <a href="{$Directory}Rastreamento">Rastreamento</a>
        <a href="{$Directory}Contato">Contato</a>
    </nav>
    <div class="CorpoMarcador">
        <div class="MarcadorMenu" style="width: 66px; height: 5px; left: 35px;"></div>
    </div>
</section>

CSS

.MenuHead {width: 100%; height: 55px; background: blue;}
.CorpoMenuHead{width: 987px; height: 50px; margin: auto;}
.CorpoMenuHead a{height: 50px; line-height: 50px; display: block; float: left; margin: 0 10px; padding: 0 30px; font-family: 'roboto_condensedregular',sans-serif; font-size: 15px; color: #FFFFFF;}
.CorpoMarcador {width: 1000px; height: 5px; margin: auto; position: relative;}
.MarcadorMenu {position: absolute; background: #FFBF00;}

JavaScript

$(document).ready(function(){
    var Status = 1;
        var LeftInicial = $('.MarcadorMenu').css('left');
        var WidthInicial = $('.MarcadorMenu').css('width');
        $('.CorpoMenuHead').hover(function(){
            $('.CorpoMenuHead').on('mousemove', function(e){
                var Tam1 = $('.MenuHead').innerWidth();
                var Tam2 = $('.CorpoMenuHead').innerWidth();
                if(Status==1){
                    $('.MarcadorMenu').stop().animate({
                        left: e.pageX -(Tam1-Tam2)/2-50,
                        width: '100px'
                    });
                    Status=0;
                }else{
                    $('.MarcadorMenu').css({
                        left: e.pageX -(Tam1-Tam2)/2-50,
                        width: '100px'
                    });                    
                }
            });
        },function(){
            $('.MarcadorMenu').animate({
                left: LeftInicial,
                width: WidthInicial
            });
            Status=1;
        });
    });