otp.css

* {
  box-sizing: border-box;
}
h1 {
  margin-bottom: 15px;
}

#main {
  width: 30%;
  margin: auto;
  margin-top: 20px;
  text-align: center;
  padding: 20px;
  padding-top: 5px;
  box-shadow: rgba(0, 0, 0, 0.24) 0px 3px 8px;
  border-radius: 15px;
}

label {
  display: block;
  font-size: 20px;
  margin: 32px auto 10px auto;
}
form [type="submit"] {
  display: block;
  margin: 40px auto 5px auto;
  padding: 10px 10px;
  border: white solid;
  font-size: 20px;
  width: 100%;
  border-radius: 8px;
}
form [type="submit"]:hover {
  cursor: pointer;
  background-color: grey;
  color: white;
  font-weight: bold;
}

#otp {
  border-radius: 8px;
  font-size: 20px;
  width: 100%;
  padding-bottom: 10px;
  padding-top: 10px;
  padding-left: 10px;
  border: 0.5px solid rgb(206, 204, 204);
}