.body {
    display: grid;
}

.container-middle {
    max-width: 640px;
    margin: 1em auto;
    padding: 1em;
    font-family: serif;
    text-align: center;
    font-size: 18px;
    overflow: hidden;
}

nav a.button {
    padding: 0.5em 1em 0.4em;
}

a.button {
  display: inline-block;
  background: white;
  color: black;
  border: 1px solid #d1d1d1;
  text-decoration: none;
  padding: 0.6em 1em;
  border-radius: 1.5em;
  margin: 0 0.2em 0.75em;

}

a.button:hover,
a.button.current {
  background: #f0f0f0;
}