@media screen and (max-width: 736px) {
  #bg div.visible {
    animation: none;
    width: 100%;
    left: 0;
    background-position: center;
  }

  #main-container.no-blur {
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
  }

  #main-container {
    width: 95%;
    padding: 2em 1em;
    background-color: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-radius: 15px;
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
    border: 1px solid rgba(255, 255, 255, 0.2);
  }

  #header h1 {
    font-size: 2.5em;
  }

  #header p {
    font-size: 1.1em;
  }

  #signup-form input[type="url"] {
    width: 100%;
  }

  #advanced-options {
    width: 100%;
  }

  #captcha-modal {
    left: unset;
    width: 100%;
    height: 100%;
  }

  #captcha-modal .modal-content {
    width: 100%;
    height: 100%;
  }

  #alert-ok-btn {
    width: 100%;
  }
}

@media screen and (max-width: 480px) {
  body {
    padding: 0.5em;
  }

  #main-container {
    width: 100%;
    padding: 1.5em 0.5em;
  }

  #header h1 {
    font-size: 2em;
  }

  #header p {
    font-size: 1em;
  }

  #signup-form {
    flex-direction: column;
    align-items: center;
  }

  #signup-form input[type="url"],
  #signup-form input[type="submit"] {
    width: 100%;
    margin: 0.5em 0;
  }
}