body {
  color: black;
  font-family: Verdana;
  background-repeat: no-repeat;
  background-attachment: fixed; 
  background-size: 100% 100%;
}

@media screen and (min-width: 601px) {
  body {
    font-size: 16px;
    background-image: url('/images/background_desktop.jpg');
    background-size: cover;    
  }
}

@media screen and (max-width: 600px) {
  body {
    background-image: url('/images/background_mobile.jpg');
    font-size: 12px;
  }
}

header {
  background-color: black;
  color: white;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;  
  padding-left: 10px;
}

header a, footer a {
  color: white;
  text-decoration: none;
  }

footer {
  background-color: black;
  color: white;
  position: fixed;
  bottom: 0;
  right: 0;
  left: 0;
  padding-right: 10px;
  text-align: right;
}

span {
  padding-right: 10px;
  }
  
article {
  display: flex;
  justify-content: center;
  align-items: center;
  }
  
.text {
  background-color: white;
  min-width: 350px;
  padding: 10px;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  }