style.css

@import url('https://fonts.googleapis.com/css2?family=Inter&display=swap');

*{
  padding: 0;
  margin: 0px;
  font-family: 'Inter', sans-serif;
  text-align: center;
}

h1{
  color: black;
  padding: 20px;
  text-align: center;
  font-weight: 400 !important;
  letter-spacing: 1px;
  background-color: rgb(188, 205, 255);
  border-radius: 50px;
  margin: calc(25% + 5px);
  margin-top: 40px !important;
  margin-bottom: 40px !important;
}

h2{
  color: black;
  padding: 15px;
  text-align: center;
  font-weight: 200 !important;
  letter-spacing: 1px;
  background-color: rgb(227, 234, 255);
  border-radius: 50px;
  margin: calc(25% + 5px);
  margin-top: 40px !important;
  margin-bottom: 40px !important;
}

h4{
  color: black;
  padding: 8px;
  text-align: center;
  font-weight: 600;
  letter-spacing: 1px;
  background-color: rgb(235, 240, 255);
  border-radius: 50px;
  margin: calc(41% + 5px);
  margin-top: 10px !important;
}

h5{
  color: black;
  padding: 8px;
  text-align: center;
  font-weight: 600;
  letter-spacing: 1px;
  background-color: rgb(235, 240, 255);
  border-radius: 50px;
  margin: calc(33% + 5px);
  margin-top: 10px !important;
}

#num-tarjetas, #input{
  padding: 4px;
  margin: 2px;
  width: 15%;
  border-radius: 15px !important;
  border-color: rgb(213, 213, 213);
  border-style: solid;
}

#tarjetas-form{
  margin-bottom: 30px !important;
}

#button{
  padding: 5px;
  margin: 15px;
  width: 15%;
  border-radius: 15px !important;
  border-color: rgb(209, 240, 207);
  background-color: rgb(240, 254, 238);
  border-style: solid;
}

#button:hover{
  border-color: rgb(176, 222, 172);
  background-color: rgb(205, 255, 197);
  border-style: solid;
  transition: 0.2s ease;
}

#back{
  padding: 5px;
  margin: 15px;
  width: 15%;
  border-radius: 15px !important;
  border-color: rgb(240, 207, 207);
  background-color: rgb(254, 238, 238);
  border-style: solid;
}

#back:hover{
  border-color: rgb(239, 193, 193);
  background-color: rgb(255, 218, 218);
  border-style: solid;
  transition: 0.2s ease;
}