.calc-wrapper {
  max-width: 600px;
  margin: 0 auto;
  border: 1px solid #ddd;
  padding: 20px;
  font-family: Arial;
}

.calc-steps {
  margin-bottom: 15px;
  font-size: 14px;
  color: #666;
}

.calc-title {
  font-size: 20px;
  margin-bottom: 15px;
}

.calc-step {
  display: none;
}

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

.calc-nav {
  margin-top: 20px;
  display: flex;
  justify-content: space-between;
}

.calc-error {
  color: red;
  font-size: 13px;
}

.calc-result {
  font-size: 22px;
  font-weight: bold;
  margin-bottom: 15px;
}