#prelaunch-popup {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: rgba(0,0,0,0.6);
    z-index: 9999;
    display: none;
}
.popup-content {
    background: white;
    color: black;
    max-width: 400px;
    margin: 15% auto;
    padding: 20px;
    text-align: center;
    border-radius: 10px;
    font-size: 16px;
}
#close-prelaunch {
    margin-top: 10px;
    padding: 8px 16px;
    background: #000;
    color: #fff;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}