.box_kensaku {
    position: relative;
  }
  .box_kensaku .error {
    display: none;
    position: absolute;
    top: 3em;
    left: 0;
    padding: .2em .5em .3em;
    background-color: #f66;
    border: 1px solid #f00;
    border-radius: 5px;
    color: #fff;
  }
  .box_kensaku .error:after,
  .box_kensaku .error:before {
    content: '';
    position: absolute;
    bottom: 100%;
    left: 15px;
    border: solid transparent;
  }
  .box_kensaku .error:after {
    margin-left: 1px;
    border-bottom-color: #f66;
    border-width: 7px;
  }
  .box_kensaku .error:before {
    border-bottom-color: #f00;
    border-width: 8px;
  }