.botten_otoiawase {
    background-color: #0084db;
    position: absolute;
    display: block;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    content: "";
    border-radius: inherit;
}

.botten_otoiawase:hover {
  background-color: #83d0fc;
}