You'll need to change these in your css: (Any commented property should be removed)
.navbar ul {
/* letter-spacing: -0.01em; */
}
.navbar .nav {
border-right: 2px solid black;
/* position: relative; */
/* left: 0; */
display: inline-block;
/* float: left; */
margin: 0;
/* width: 100%; */
/* height: 10px; */
}
.navbar li {
/* width: auto; */
/* display: block; */
display: inline-block;
margin-bottom: 0;
/* line-height: 40px; */
/* font-size: 14px; */
}
.navbar {
text-align: center;
}
And remove the ".divider-vertical" li, is not needed, it adds no semantic value to your code.