p {
  line-height:150%;  letter-spacing: 1px;
  }

div {background-color: #ffff;
  font-style: normal;
  font-family: Arial, Helvetica, sans-serif;
  margin: auto;
  max-width:700px;
  padding: 14px;
  border-style: solid;
  border-color: silver;
  border-radius: 15px;
  }

body {margin: 0;
      background-color: #ffffe0;
   }


a:link, a:visited {
  background-color: #f5f5f5;
  width: 200px;
  height: 15px;
  padding:14px;
  margin: 5px;
  border-style: solid; 
  border-color: silver;
  text-align: center;
  border-radius: 10px;
  text-decoration: none;
  display: inline-block;
  font-size: 15px;
 }

pre { 
 font-size: calc( 8px + (6 – 5) * ( (100vw – 400px) / ( 700 – 400) )); 
 background: black;
 color: white;
 margin: 0 auto;
 overflow: auto;
}