body {
  font-family: Arial;
  background: #f1f1f1;
  display: flex;
  justify-content: center;
  padding-top: 80px;
}

.box {
  background: white;
  width: 320px;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 3px 10px rgba(0,0,0,0.1);
  text-align: center;
}

input {
  width: 100%;
  padding: 10px;
  margin: 10px 0;
}

button {
  width: 100%;
  padding: 10px;
  background: black;
  color: white;
  border: none;
  cursor: pointer;
}

.step {
  display: none;
}

.active {
  display: block;
}