:root {
  --light: #fff;
  --dark: #000;
}

body {
  background: url('/images/backgrounds/gray.jpg') no-repeat center center fixed;
  background-size: cover;
  font-size: 20px;
  line-height: 2;
}

main {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 2rem;
  min-block-size: 100vh;
}

a {
  display: grid;
  place-items: center;
  min-inline-size: 400px;
  min-block-size: 200px;
  background-color: var(--light);
  color: var(--dark);
  text-align: center;
  border: 3px solid var(--light);
  border-radius: 1rem;
}

a:hover {
  background-color: var(--dark);
  color: var(--light);
}