* {
    box-sizing: border-box;
}

body {
    background: url('Images/wallpaper.jpeg') no-repeat center center fixed;
    background-size:cover;
}

header {
    /*background-color: black;
    padding: 30px;
    text-align: center;
    font-size: 35px;
    color: white;*/
    position: fixed;
    top: 0px;
    left: 0px;
    min-width: 700px;
    z-index: 1;
    width: 100%;
    background-color: black;
    padding-bottom: 10px;
    color: white;
    font-family: serif;
    font-weight: bold;
}
article {
    align-content: center;
    padding: 20px;
    width: 70%;
    background-color: #f1f1f1;
    /*height: 300px; *//* only for demonstration, should be removed */
    height: 75vh;
    overflow: auto;
    padding: 12px;
    padding-top: 80px; /* prevent the top of the content from getting hidden under the fixed titleNav */
    padding-bottom: 60px; /* prevent the the bottom of the content from getting hidden under the fixed footer */
}

footer {
    position: fixed;
    bottom: 0px;
    left: 0px;
    z-index: 1; /* make sure footer is on top of content which would have default z-index value of 0 */
    background-color: black;
    color: white;
    width: 100%;
    text-align: center;
    padding: 8px;
}