* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  color: #000;
  background: #ffff00;
  font-family: Arial, Helvetica, sans-serif;
}

main {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1.5rem;
  padding: 1.5rem;
}

h1 {
  max-width: 14ch;
  margin: 0;
  font-size: clamp(3rem, 13vw, 8rem);
  line-height: 1.05;
}

p {
  margin: 0;
  font-size: clamp(2rem, 9vw, 5rem);
  font-weight: 700;
}

nav {
  display: flex;
  flex-direction: column;
  gap: .75rem;
  width: min(100%, 30rem);
}

a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 3.25rem;
  padding: .75rem 1rem;
  border: 2px solid #000;
  color: #fff;
  background: #0000ff;
  box-shadow: .35rem .35rem 0 #000;
  font-size: 1.25rem;
  font-weight: 700;
  text-decoration: none;
}

.back {
  width: fit-content;
  min-width: 8rem;
}

@media (min-width: 768px) {
  main {
    padding: 3rem;
  }

  nav {
    flex-direction: row;
    width: auto;
  }
}