* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  padding: 20px;
}

h1 {
  text-align: center;
}

p {
  margin-bottom: 10px;
}

.input-group {
  display: flex;
  align-items: center;
  margin-bottom: 10px;
}

.input-group label {
  width: 150px;
}

.input-group input {
  width: 100px;
}

button {
  display: block;
  margin: 0 auto;
}

#result {
  margin-top: 20px;
}