.blocker {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    z-index: 9999;
    padding: 20px;
    box-sizing: border-box;
    background-color: rgb(0,0,0);
    background-color: rgba(0,0,0,0.75);
    text-align: center;
}