body {
    background-color: white;

    text-align: center;
    font-family: Helvetica,Arial,sans-serif;
    min-width: 580;
    width: 80%;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

h1, h2, h3, h4, h5 {
    margin-top: 50px;
    margin-bottom: 50px;
}

h2, h3, h4, h5 {
    border-bottom: 3px solid;
}

p {
    text-align: left;
}

img figure {
    text-align: left;
}

ul, li, ol {
    text-align: left;
}

:root {
    --width:250px;
    --height:calc(var(--width) / 2);
  }

.ball {
    width: var(--width);
    height: var(--height);
    background: url(./images/dvd.png);
    background-size: contain;
    background-repeat: no-repeat;
    position:absolute;
  
    animation: toRight linear 6.8s infinite alternate, bounce linear 17s infinite alternate;
  }