body, html {
  margin: 0;
  padding: 0;
  font-family: Arial, sans-serif;
  background-color: #e0e0e0;
}

.toolContainer {
  position: relative;
  max-width: 720px;
  margin: 2rem auto;
  padding: 1.5rem 2rem;
  background-color: #f9f9f9;
  border-radius: 8px;
  box-shadow: 0 5px 15px rgba(0,0,0,0.1);
  box-sizing: border-box;
}

form {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

fieldset {
  border: 1px solid #ccc;
  border-radius: 6px;
  padding: 0.75rem 1rem 1rem;
}

legend {
  font-weight: bold;
  margin-left: 8px;
}

label {
  display: block;
  margin: 0.5rem 0 0.25rem;
  font-weight: 600;
}

input[type="number"] {
  width: 100%;
  padding: 0.4rem 0.5rem;
  border: 1px solid #bbb;
  border-radius: 4px;
  font-size: 1rem;
  box-sizing: border-box;
}

input[type="radio"] {
  margin-right: 0.3rem;
}

button[type="submit"] {
  background-color: #007acc;
  color: white;
  border: none;
  border-radius: 6px;
  padding: 0.75rem;
  cursor: pointer;
  font-size: 1.2rem;
  font-weight: bold;
  transition: background-color 0.25s ease;
}

button[type="submit"]:hover,
button[type="submit"]:focus {
  background-color: #005fa3;
  outline: none;
}

#result {
  font-size: 1.1rem;
  font-weight: 600;
  color: #222;
  background-color: #e6f0ff;
  border: 1px solid #99c2ff;
  border-radius: 6px;
  padding: 1rem;
}

@media (max-width: 480px) {
  .toolContainer {
    margin: 1rem;
    padding: 1rem;
  }
  button[type="submit"] {
    font-size: 1rem;
    padding: 0.6rem;
  }
}