body {
      font-family: "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
      background-color: #fff;
      margin: 0;
      padding: 0;
      color: #333;
    }

    header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      padding: 10px 20px;
      border-bottom: 4px solid #f5c1c1;
    }

    .logo {
      display: flex;
      align-items: center;
      justify-content: space-around;
      width:33%;
    }

    .logo img {
      height: 74px;
      margin-right: 10px;
    }

    .title-block {
      width:33%;
      flex-grow: 1;
      text-align: center;
      margin-top: 10px;
      margin-bottom: 10px;
    }

    .title-block h1 {
      font-size: 1.3rem;
      margin: 0;
      font-weight: bold;
    }

    .title-block p {
      margin: 5px 0 0;
      font-size: 1rem;
    }

    .container {
      max-width: 600px;
      margin: 30px auto;
      padding: 20px;
      border: 1px solid #ddd;
      border-radius: 8px;
      background-color: #f9f9f9;
    }

    .description {
      background-color: #fff;
      border: 1px solid #ccc;
      padding: 15px;
      margin-bottom: 20px;
      font-size: 0.95rem;
      line-height: 1.6;
    }

    .description .note {
      color: blue;
      font-size: 0.9rem;
      line-height:1.4;
      padding:0px 10px;
    }

    form {
      background-color: #fff;
      padding: 20px;
      border-radius: 6px;
      border: 1px solid #ccc;
    }

    label {
      display: block;
      margin-bottom: 8px;
      font-weight: bold;
    }

    input[type="email"] {
      width: 100%;
      padding: 12px;
      font-size: 1rem;
      border: 1px solid #ccc;
      border-radius: 4px;
      margin-bottom: 20px;
      box-sizing: border-box;
    }

input[type="submit"] {
      width: 100%;
      padding: 12px;
      font-size: 1rem;
      background-color: #1E90FF;
      color: white;
      border: none;
      border-radius: 4px;
      cursor: pointer;
      transition: background-color 0.3s;
}
input[type="submit"]:hover {
  background-color: #999;
}
input[type="submit"]:disabled,input[type="submit"]:disabled:hover{
  cursor:default;
  background-color: #999;
}

/*
.btn_back {
  background-color: #2fb4d5;
  color: #fff;
  padding: 10px 30px;
  text-decoration: none;
  font-size: 1em;
}
*/
.btn_back {
  text-decoration: none;
  font-size: 1em;
  text-shadow: 1px 2px 3px #808080;
  background-color: #cff;
  padding: 3px 30px;
  box-sizing: border-box;
  color:blue;
}
.btn_back:hover {
  color: #333;
  opacity: 0.8;
  background-color: #ccc;
}
.btn_back:visited{
  color:blue;
}


.subject{
  border-bottom:1px solid #999; text-align:center;margin: 0px auto; font-size: 20px;
}
.letter{
  background-color:#fcfcfc; font-size:14px; padding:0px;line-height:1.4;
}

#email-warning {
  color: red;
  text-align:center;
  font-weight:bold;
  font-size:12px;
  display: none;
}


    @media (max-width: 600px) {
      header .logo{
        width:100%;
      }
      header .title-block{
        width:100%;
        margin:0px auto;
      }
      header p{
        display:none;
      }
      .title-block h1 {
        font-size: 1.1rem;
      }

      .title-block p {
        font-size: 0.9rem;
      }

      .container {
        margin: 20px;
        padding: 15px;
      }
    }