.loader {
    position: fixed;
    left: 0px;
    top: 0px;
    width: 100%;
    height: 100%;
    z-index: 9999;
    background: url('../img/loading.gif') 50% 50% no-repeat white;
}  

.ui.modal.transition.visible.active{
    height: auto;
}

.hidden{
    display: none;
}