body {
  font-family: sans-serif;
  text-align: center;
  margin-top: 80px;
  background: #111;
  color: #eee;
  padding: 20px;
  font-size: 18px;
}

body {
  font-family: sans-serif;
  margin: 0;
  padding: 20px;
  font-size: 18px;
}

button {
  font-size: 20px;
  padding: 10px 20px;
}

input[type="range"] {
  width: 100%;
}