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  <label for="email">メールアドレス:</label>
  <input type="email" id="email" name="email" placeholder="[email protected]" size=40 />
  <div id="error-msg-email" class="error-msg" style="display: none;"></div>


                /* フォーカスが当たった時の青枠を表示しない */
*:focus {
  outline: none;

div.input-area {
  margin: 15px 0 10px 10px;

div.input-area label {
  display: inline-block;
  width: 8rem;
  text-align: right;

div.error-msg p {
  color: #d00;
  margin: 0 0 0 8rem;

input[type="email"] {
  line-height: 2em;

.input-error {
  border: 1px solid #d00;
  border-radius: 3px;
  background-color: #FCC;



                $(function () {
  // フォーカスが当たった場合のイベントハンドラ
  $("#email").on("focus", function () {
    $("#error-msg-email p").remove();

  // フォーカスが外れた場合のイベントハンドラ
  $("#email").on("blur", function () {
    // トリム
    // 入力チェック

 * メールアドレスの入力チェック
function validate_email() {
  var val = $("#email").val();
  // 必須チェック
  if (val == "") {
  // メール形式チェック
  else if (!val.match(/^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*$/)) {