header {
    height: 100vh;
    background-image: url(../img/background.jpg);
    background-position: center, center;
    background-size: cover;
    display: flex;
    -ms-flex-direction: column;
    -webkit-flex-direction: column;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

h1{
    text-align:center;
    font-size: 4.5vw;
    font-family: 'Raleway', sans-serif;
    color:#fff;
    text-shadow: 1px 1px 5px rgba(0, 0, 0, 0.4);
    opacity:0.8;
}

h2{
    text-align:center;
    font-size: 3vw;
    font-family: 'Raleway', sans-serif;
    color:#fff;
    text-shadow: 1px 1px 5px rgba(0, 0, 0, 0.4);
    opacity:0.7;
}