#startup {
    background-color: black;
    opacity: 0.8;
    width: 100%;
    height: 100%;
    position: absolute;
    z-index: 100;
}

#startup-content {
    position: absolute;
    z-index: 100;
    top: 20%;
    left: 20%;
    width: 60%;
    background-color: rgb(240, 240, 240);
    padding: 25px;
    border: 2px solid black;
    border-radius: 10px;
}

#x {
    position: absolute;
    top: 100px;
    right: 150px;
    width: 30px;
    height: 30px;
    background-color: black;
    z-index: 101;
    border: 3px solid white;
    border-radius: 50%;
}

#x:hover {
    cursor: pointer;
}

.X1 {
    position: absolute;
    background-color: white;
    top: 14px;
    left: 6px;
    height: 3px;
    width: 18px;
    transform: rotateZ(45deg);
}

.X2 {
    position: absolute;
    background-color: white;
    top: 14px;
    right: 6px;
    height: 3px;
    width: 18px;
    transform: rotateZ(-45deg);
}

li {
    padding: 2px;
}