.topnav{
    width: 100%;
    height: 140px;
    background-color: #ffffff;
    position: relative;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.topnav .toplogo{
    width: 420px;
    height: 130px;
    margin-left: 15%;
    background: url(../img/DenovoNeuro_logo_full.png) no-repeat center center;
    background-size: 100% 100%;
}
.topnav .topbtn{
    border: none;
    margin-right: 15%;
    width: 100px;
    height: 100px;
    background: url(../img/iconmenu.png) no-repeat center center;
    background-size: 100% 100%;
}
.topnav .slidemenu{
    font-weight: bold;
    font-size: 42px;
    width: 42%;
    height: auto;
    display: none;
    background-color: #ffffff;
    position: absolute;
    z-index: 9999;
    right: 0;
    top: 140px;    
}

.topnav .slidemenu a{
    color: #000000;
}
.topnav .slidemenu .mainul li{
    width: 100%;
    margin: 50px 0;
    text-align: center;
}
.topnav .slidemenu .secmenu1 span{
    display: inline-block;
    margin-left: 40px;
    width: 20px;
    height: 30px;
    background: url(../img/backblack.png) no-repeat center center;
    background-size: 100% 100%;
}
.topnav .slidemenu .secmenu1 ul li {
    font-size: 36px;
    font-weight: none;

}
.topnav .slidemenu .secmenu2 span{
    display: inline-block;
    margin-left: 40px;
    width: 20px;
    height: 30px;
    background: url(../img/backblack.png) no-repeat center center;
    background-size: 100% 100%;
}
.topnav .slidemenu .secmenu2 ul li {
    font-size: 36px;
    font-weight: none;

}