.side-nav {
    margin: 12px 0;
    list-style-type: none;
    padding: 0;
}

.side-nav li {
    padding: 4px 7px;
    color: #eee;
    cursor: pointer;
    font-size: 15px;
}

.nav-category-links {
    background-color: #ddd;
    display: none;
}

.nav-category-links ul {
    margin: 0;
    padding: 0;
    list-style-type: none;
}

.nav-category-links li {
    padding: 0;
    font-size: 14px;
}

.nav-category-links li a {
    text-decoration: none;
    display: block;
    padding: 4px 7px;
    color: #333;
}

.nav-category-links li a:hover {
    background-color: #fff;
    color: #000;
}

.active-nav-category {
    background-color: #000;
    color: #fff;
    font-weight: bold;
}

.open-nav-links {
    display: block;
}