.energie-rechner {
  max-width: 400px;
  margin: 0 auto;
  font-family: sans-serif;
}

.rechner-step {
  display: none;
  padding: 20px;
  border-radius: 16px;
  background: rgba(255,255,255,0.85);
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
  margin-bottom: 20px;
}

.rechner-step.active {
  display: block;
}

.cards {
  display: flex;
  gap: 10px;
  flex-direction: column;
}

.card-btn {
  padding: 15px;
  border: none;
  border-radius: 12px;
  background: rgba(0, 123, 255, 0.8);
  color: white;
  cursor: pointer;
  font-size: 16px;
}

.card-btn:hover {
  background: rgba(0, 123, 255, 1);
}

input, button {
  width: 100%;
  margin: 8px 0;
  padding: 10px;
  border-radius: 8px;
  border: 1px solid #ccc;
}

button.next-step {
  background: #28a745;
  color: white;
  border: none;
  font-size: 16px;
  cursor: pointer;
}

button.next-step:hover {
  background: #218838;
}