html , body {
    overflow: hidden;
    height: 100%;
}
#content {
    height: 62%;
}
#sidebar {
    width: 200px;
    height: 80%;
    color: black;
    position: absolute;
    font-size: 18px;
    border-right: 3px solid rgba(0,0,0,0.1);
}
#sidebar > div > a {
    color: black;
    text-decoration: none;
}
#sidebar > div > a > img , #sidebar > div > img {
    width: 20px;
    margin-right: 10px;
    position: relative;
    top: 3px;
}
.nav-item {
    width: 200px;
    cursor: pointer;
    padding: 15px 0 15px 20px;
}
.nav-submenu {
    display: none;
    list-style: none;
    padding: 0;
}
.nav-submenu a {
    display: block;
    padding: 30px 30px 0 50px;
    color: black;
    text-decoration: none;
}
#content-frame {
    width: calc(100% - 200px);
    height: 80vh;
    float: right;
    position: relative;
    top: 0;
    border: none;
}