@media only screen and (min-width:900px)
{
    .desktop{
        display: block;
    }
    .topic {
        margin: auto;
        margin-top: 100px;
        margin-bottom: 50px;
        width: 90%;
        background-image: none;
        background-color: rgba(255,255,255, 0.9);
        padding: 35px;
        border-radius: 10px;
        box-shadow: 5px 5px 5px #000;
    }
    .menuTopic {
        overflow: hidden;
        position: fixed;
        top: 0px;
        z-index: 1;
    }
    .menuTopic .right {
        display: block;
    }
    .photosite {
        display: block;
        width: 95%;
        margin:auto;
        margin-top: 4em;
        border-radius: 10px;
    }
}