body {
  font-family: system-ui, sans-serif;
  background: #1e2a1e;
  color: #f2f2f2;
  margin: 0;
}

main {
  max-width: 600px;
  margin: 0 auto;
  padding: 1.5rem;
}

h1 {
  text-align: center;
  color: #7ddc5a;
}

button {
  display: block;
  width: 100%;
  margin: 0.5rem 0;
  padding: 0.8rem;
  font-size: 1.1rem;
  border: none;
  border-radius: 8px;
  background: #3b5e3b;
  color: inherit;
  cursor: pointer;
}

button:hover:not(:disabled) {
  background: #4f7d4f;
}

button.richtig {
  background: #2e9e3e;
}

button.falsch {
  background: #b03a3a;
}

#rueckmeldung {
  min-height: 1.5em;
  font-weight: bold;
}