* {
  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: 500px;
  max-width: 800px;
  background: #fff;
  border-radius: 10px;
  border: 2px solid #000;
  padding: 20px 25px 0;
  transition: 0.2s ease;
}

.qr_box.active {
  height: 600px;
}

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;
  }
}