@media screen and (min-width:1200px){ 
    header {
        position: fixed;
        width: 100%;
        background: #FFF;
        height: 70px;
        left: 70%;
        transform: translate(-50%, 0);
        background-color: #000
    }

    #Menu {
        height: 100%;
        position: relative;
        width: 100%;
        transform: translateX(0px);
        transition: transform 250ms ease-in-out;
        font-size: 25px;
    }
    .MenuInner{
        margin:0;
        padding:0;
    }
    .MenuInner li{
        list-style: none;
        display: inline-block;
        background: #000;
        color: #fff;
        cursor: pointer;
    }

    .MenuInner li:hover{
        background: #fff;
    }

    .MenuInner li a{
        color: #fff;
        padding: 10px;
        text-decoration: none;
    }

    .MenuInner li:hover a{
        color: #000;
    }