HTMLify

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "sans";
  }

  @font-face {
      font-family: "sans";
      src: url(font/sans.ttf);
  }

  html,
  body {
    height: 100%;
  }
  
  body {
    display: flex;
    align-items: center;
    justify-content: center;
    background: #19172e;
  }
  
  h2 {
    position: absolute;
    top: 0;
    padding-top: 100px;
    color: white;
    font-size: 2rem;
    text-align: center;
  }

  #qr {
    position: relative;
  }
  
  #qr::before {
    content: "";
    display: block;
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
  
    /* don't go to big. otherwise the qr code is may not readable anymore */
    width: 36%;
    height: 36%;
    border-radius: 50%;
  
    background: url(assets/img.png)
    no-repeat center;
    background-size: cover;
  }
  
  footer {
    background-color: #19172e;
    text-align: center;
    color: white;
    font-size: 1rem;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    margin-bottom: 0;
    padding: 5px;
    line-height: 3vh;
  }
  
  footer a:visited {
    color: inherit;
  }