.dialog {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    width: 300px;
    height: 200px;
    box-shadow: 15px 15px 10px #888888;
    padding: 15px;
    z-index: 999;
    border: 5px solid red;
    text-align:center;
}