/* #counter has its own :active feedback below; without this, mobile browsers
   also flash their default gray tap-highlight box on top of it. */
* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: red;
  color: #fff;
}

main {
  text-align: center;
  padding: 2rem;
}

h1 {
  font-size: 2.5rem;
  margin: 0 0 0.5rem;
}

#tagline {
  margin: 0 0 1.5rem;
  opacity: 0.8;
}

#counter {
  font-size: 1rem;
  padding: 0.6rem 1.4rem;
  border: 1px solid #fff;
  border-radius: 8px;
  background: transparent;
  color: #fff;
  cursor: pointer;
}

#counter:active {
  background: rgba(255, 255, 255, 0.2);
}