* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  width: 100%;
  min-height: 100%;
}

body {
  font-family:
    sans-serif;

  color: #333;
  background: #f5f6f8;
}
/* ========================================
   Container
   ======================================== */

.container {
  width: 100%;
  padding: 30px 20px;
  min-height: 100vh;

  display: flex;
  align-items: center;
  justify-content: center;
}

.form-area {
  width: 100%;
  max-width: 800px;
  

  background: #fff;
  border: 1px solid #ddd;
  border-radius: 6px;

  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);

  overflow: hidden;
  padding: 0 50px;
}

/* ========================================
   ページタイトル
   ======================================== */

.page-title {
    margin: 0 0 30px;
    font-size: 24px;
    text-align: center;
    margin-top: 20px;

}

/* メッセージ */
.message {
    margin-bottom: 20px;
    padding: 12px 15px;
    border-radius: 5px;
    font-size: 14px;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 15px;
}

.error-message {
    border: 1px solid #e57373;
    background-color: #ffebee;
    color: #c62828;
}

.success-message {
    border: 1px solid #64b5f6;
    background-color: #e3f2fd;
    color: #1565c0;
}

/* メッセージ閉じるボタン */
.message-close {
    flex-shrink: 0;
    border: none;
    background: transparent;
    color: inherit;
    font-size: 22px;
    line-height: 1;
    cursor: pointer;
    padding: 0 4px;
}

.message-close:hover {
    opacity: 0.6;
}

/* ========================================
   form
   ======================================== */

.form-control {
   display: block;

   width: 100%;
   height: 46px;

   margin: 3px 0 15px;
   padding: 10px 14px;

   color: #333;
   font-size: 16px;
   line-height: 1.5;

   background: #fff;
   border: 1px solid #ccc;
   border-radius: 4px;

   outline: none;

   transition:
      border-color 0.2s ease,
      box-shadow 0.2s ease;
}

.form-control::placeholder {
   color: #999;
}

.form-control:focus {
   border-color: #66afe9;

   box-shadow:
      0 0 0 3px rgba(102, 175, 233, 0.2);
}

/* ========================================
   送信ボタン
   ======================================== */

button[type="submit"] {
   display: block;

   width: 100%;
   min-height: 46px;

   margin-top: 20px;
   padding: 10px 20px;

   color: #fff;
   background: #1B348A;

   border: 1px solid #1B348A;
   border-radius: 4px;

   font-family: inherit;
   font-size: 16px;
   font-weight: 600;

   line-height: 1.5;

   cursor: pointer;

   transition:
      background-color 0.2s ease,
      border-color 0.2s ease,
      box-shadow 0.2s ease;
}

button[type="submit"]:hover {
   background: #0c7bbb;
   border-color: #1B348A;
}

button[type="submit"]:focus {
   outline: none;

   box-shadow:
      0 0 0 3px rgba(51, 122, 183, 0.25);
}

button[type="submit"]:active {
   background: #2545B0;
   border-color: #1B348A;
}

/* ========================================
   back
   ======================================== */
.back-login {
   text-align: center;
   margin-top: 20px;
   margin-bottom: 20px;
}
.back-login a {
   text-decoration: none;
}
.back-login a:hover {
   text-decoration: underline;
}

/* ========================================
   レスポンシブ
   ======================================== */
@media (max-width: 900px) {
    .container {
        padding-left: 10%;
        padding-right: 10%;
    }

    .form-area {
        padding-left: 8%;
        padding-right: 8%;
    }
}

@media (max-width: 600px) {
    .container {
        padding: 20px 15px;
    }

    .form-area {
        padding: 0 20px;
    }

    .page-title {
        font-size: 20px;
        margin-bottom: 20px;
    }
}