html {
  --accent-color: grey;
}

body {
  max-width: 800px;
  margin: 0 auto;
  font-family: sans-serif;
  padding: 20px;
}

h1 {
  color: var(--accent-color);
  text-align: center;
  
}

ul {
  margin: 0;
  padding: 0;
}

ul li {
  display: inline;
}

ul li a {
  text-decoration: none;
  font-weight: bold;
  padding: 0 1em;
  border: 2px solid grey;
  opacity: 0.7;
  border-top-left-radius: 0.5em;
  border-top-right-radius: 0.5em;
}
ul li a:hover {
  border-bottom-color: white;
  opacity: 1;
}

.current {
  opacity: 1;
}  

main {
  border: 2px solid grey;
  padding: 1.5em
}
  
main h2 {
  border-bottom: 2px dashed grey;
  margin: 0;
}

main a {
  color: red;
}

main p {
  text-align: center;
  color: grey;
  font-size: smaller;