.share .hidden_show {
    position: absolute;
    height: 0;
    padding: 0;
    overflow: hidden;
    opacity: 0;
    transition: 0.8s;
    z-index: 999;
    left: calc(50% - 140px);
}

.share input:checked ~ .hidden_show {
    padding: 10px 0;
    height: auto;
    opacity: 1;
    width: 100%;
    max-width: 280px;
    text-align: center;
}

.share form{
    background-color: #dedede;
    padding: 5px;
}