.sec-campaign-cont {
    max-width: 460px;
    margin: 40px auto;
    text-align: center;
}

.sec-campaign-cont h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 30px;
} 

.phonebox img {
    display: inline-block;
    width: 40px;
    vertical-align: middle;
    margin-right: 7px;
    margin-top: -7px;
}

.phonebox a {
    display: block;
    max-width: 460px;
    margin: 5% auto;
    line-height: 150%;
    font-size: 13px;
    letter-spacing: 1px;
    padding: 20px 0px 10px 10px;
    border: 1px solid #ccc;
    cursor: pointer;
}

.phonebox a:hover {
  opacity: 0.8;
  background-color: #f4f9f6;
}

.phonebox a p {
    font-size: 30px;
    font-weight: 600;
    padding-bottom: 15px;
}

.btn-container{
  display: flex;
  justify-content: center;
  margin-top: 50px;
}

.btn-container .btn {
  display: inline-block;
  width: 460px;
  padding: 15px 10px;
  background-color: #51a9a9;
  color: #ffffff;
  text-decoration: none;
  border-radius: 6px;
  /* 下部に影をつけて立体感を出す */
  box-shadow: 0 4px 0 #368282;
  /* 動きを滑らかにする */
  transition: transform 0.5s ease, box-shadow 0.5s ease;
}

.btn-container .btn:hover {
  transform: translateY(4px);
  box-shadow: 0 0 0 #368282;
}