style.css

/* Import Google font - Poppins */
@import url("https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700&display=swap");

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
}

body {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #95aef1;
}

:where(.container, form, .input-field, header) {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.container {
  background: #fff;
  padding: 2.5rem 5rem;
  border-radius: 0.3rem;
  row-gap: 1.3rem;
  box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
}

.container header {
  height: 65px;
  width: 65px;
  background: #4070f4;
  color: #fff;
  font-size: 2.5rem;
  border-radius: 50%;
}

.container h4{
    font-size: 1.25rem;
    font-weight: 500;
    color: #333;
}

form .input-field{
    column-gap: 10px;
    flex-direction: row;
}

.input-field input{
    height: 45px;
    width: 45px;
    border-radius: 6px;
    outline: none;
    text-align: center;
    font-size: 1.125rem;
    border: 1px solid #ddd;
}

.input-field input:focus{
    box-shadow: 0 1px 0 rgba(0, 0, 0, 0.1);
}

.input-field input::-webkit-inner-spin-button,
.input-field input::-webkit-outer-spin-button{
    display: none;
}

form button{
    width: 100%;
    color: #fff;
    border: none;
    padding: 9px 0;
    margin-top: 25px;
    font-size: 1rem;
    cursor: pointer;
    border-radius: 6px;
    pointer-events: none;
    background-color: #6e93f7;
    transition: all 0.2s ease;
}

form button.active{
    background: #4070f4;
    pointer-events: auto;
}

form button:hover{
    background-color: #0e4bf1;
}