.calculator {
  font-family: Tahoma, sans-serif;
  direction: rtl;
  background-color: white;
  padding: 20px;
  border-radius: 12px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  max-width: 600px;
  margin: auto;
}
.calculator h2 {
  text-align: center;
  margin-bottom: 20px;
  font-size: 1.4rem;
}
.form-group {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
}
.form-group > div {
  flex: 1 1 48%;
}
label {
  display: block;
  margin-bottom: 6px;
  font-weight: bold;
  font-size: 0.95rem;
}
input, select, button {
  width: 100%;
  padding: 10px;
  margin-bottom: 15px;
  border: 1px solid #ccc;
  border-radius: 8px;
  font-size: 14px;
}
button {
  background-color: #1976d2;
  color: white;
  font-weight: bold;
  cursor: pointer;
}
button:hover {
  background-color: #1565c0;
}
.result {
  background-color: #e8f5e9;
  color: #2e7d32;
  padding: 15px;
  border-radius: 8px;
  font-weight: bold;
  text-align: center;
  margin-top: 10px;
}
@media (max-width: 600px) {
  .form-group > div {
    flex: 1 1 100%;
  }
}