body {
  font-family: Arial, sans-serif;
  text-align: center;
  margin-top: 50px;
}

#batteryForm {
  margin: auto;
  width: 300px;
}

input[type=number] {
  width: 80%;
  padding: 10px;
  margin: 10px 0;
}

button {
  width: 85%;
  padding: 10px;
  background-color: #4c58ae;
  color: white;
  border: none;
  cursor: pointer;
}

button:hover {
  opacity: 0.8;
}

#result {
  margin-top: 20px;
  font-size: 20px;
  color: blue;
}