* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
  }
  
  body {
    display: flex;
    padding: 0 10px;
    min-height: 100vh;
    align-items: center;
    background: #2a3032;
    justify-content: center;
  }
  
  .qr_box {
    height: 265px;
    max-width: 410px;
    background: #fff;
    border-radius: 10px;
    border: 2px solid #000;
    padding: 20px 25px 0;
    transition: 0.2s ease;
  }
  
  .qr_box.active {
    height: 530px;
  }
  
  header h1 {
    font-size: 21px;
    font-weight: 500;
  }
  
  header p {
    margin-top: 5px;
    color: #575757;
    font-size: 16px;
  }
  
  .qr_box .form {
    margin: 20px 0 25px;
  }
  
  .form :where(input, button) {
    width: 100%;
    height: 55px;
    border: none;
    outline: none;
    border-radius: 5px;
    transition: 0.1s ease;
  }
  
  .form input {
    font-size: 18px;
    padding: 0 17px;
    border: 1px solid #999;
  }
  
  .form input::placeholder {
    color: #6f6f6f;
  }
  
  .form button {
    color: #fff;
    cursor: pointer;
    margin-top: 20px;
    font-size: 17px;
    background: #42a22b;
  }
  
  .qr-code {
    opacity: 0;
    display: flex;
    padding: 33px 0;
    border-radius: 10px;
    align-items: center;
    pointer-events: none;
    justify-content: center;
    border: 2px solid #bbb;
  }
  
  .qr_box.active .qr-code {
    opacity: 1;
    pointer-events: auto;
    transition: opacity 0.5s 0.05s ease;
  }
  
  .qr-code img {
    width: 180px;
  }
  
  @media (max-width: 430px) {
    .qr_box {
      height: 255px;
      padding: 16px 20px;
    }
  
    .qr_box.active {
      height: 510px;
    }
  
    header p {
      color: #575757;
    }
  
    .form :where(input, button) {
      height: 52px;
    }
  
    .qr-code img {
      width: 160px;
    }
  }