body {
    margin: auto;
    padding-top: 150px;
    font-family: Arial, Helvetica, sans-serif;
    background-image: url('bg.jpg');
    background-size: cover;
    background-repeat: no-repeat;
    height: 100vh;
    text-align: center;
    background-position: center;
    background-color: black;
    color: white;
    user-select: none;
    -webkit-user-select: none;
}
* {
    box-sizing: border-box;
}
.quiz-bub {
    
}