* {
    margin: 0;
}

html {
    font-family: Helvetica, sans-serif;
    height: 100%;
}

header {
    background: #000;
    height: 100vh;
    width: 100%;
}
#banner {  
    text-align: center;
    color: #fff;
    position: relative;
    top: 50%;
    transform: translateY(-50%);
    }
    
#banner img {
    width: 35vh;
    margin-top: -50px;
    }