Why isn't this navbar horizontal? Standard practice? CSS

I want my navbar to be centered and horizontal. Currently it is centered but not horizontal. How do I need to amend my current code and what are general standard practices? Thanks.

nav{
    width: 100%;
    float: left;
    position: sticky; 
    align-items: center;
    justify-content: center;
    padding: 0;
    background-color: #f2f2f2;
    border-bottom: 1px solid #ccc; 
    display: flex;
}

.nav-links li{
    list-style: none;
    text-align:center;
    padding: 14px 16px;
    font-size: 18px;
    float: center;
}

.nav-links li a{
    text-decoration: none;
    text-align:center;
}