/* ==================== スマートフォン向けスタイル (768px以下) ==================== */
@media (max-width: 768px) {
  body {
    padding: 15px;
  }

  /* index.php */
  #index-container {
    padding-top: 30px;
  }
  #index-container h1 {
    font-size: 28px;
    margin-bottom: 50px;
  }
  #index-container .btn {
    display: block;
    width: 80%;
    margin: 20px auto;
    font-size: 18px;
    padding: 15px 30px;
  }

  /* search.php */
  #search-container {
    padding: 15px;
  }
  #search-container h2 {
    font-size: 26px;
  }
  .search-form label {
    display: block;
    margin-bottom: 10px;
  }
  .search-form select,
  .search-form .btn {
    width: 100%;
    margin-right: 0;
    margin-bottom: 10px;
  }
  .item {
    padding: 10px;
    margin: 10px auto;
  }
  .item img {
    width: 100%;
    max-width: 200px;
  }
  .item p {
    font-size: 14px;
  }
  .item .btn {
    width: auto;
    display: inline-block;
  }

  /* detail.php */
  #detail-container {
    padding: 20px;
  }
  #detail-container img {
    max-width: 150px;
    margin-bottom: 15px;
  }
  #detail-container p {
    font-size: 16px;
  }
  #detail-container .btn {
    padding: 8px 15px;
    font-size: 14px;
    margin: 5px;
  }

  /* register.php */
  #register-container {
    padding-top: 20px;
    padding-bottom: 20px;
  }
  #register-container h2 {
    font-size: 26px;
  }
  #register-container label {
    width: 90%;
    max-width: unset;
    text-align: left; /* 修正: 左揃えにする */
  }
  #register-container input[type="file"],
  #register-container select,
  #register-container input[type="text"] {
    padding: 8px;
    font-size: 14px;
  }
  #register-container .btn {
    padding: 10px 20px;
    font-size: 16px;
    margin-top: 20px;
  }

  /* register_complete.php & search_complete.php */
  .complete-container {
    padding: 50px 15px;
  }
  .complete-container h2 {
    font-size: 26px;
    margin-bottom: 20px;
  }
  .complete-container p {
    font-size: 16px;
    margin-bottom: 30px;
  }
  .complete-container .btn {
    padding: 10px 20px;
    font-size: 14px;
  }
}