.demo-block {
    /*border: 1px solid red;*/
}

.container {
    position: relative;
    width: calc(100% - 20px);
    height: calc(100% - 20px);
    margin: 10px auto;
}

.box {
    /* center horizontally and vertically */
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 20px;
    height: 20px;
    background-color: #1d9a93;
    border-radius: 50%;
    cursor: pointer;
}

#box1, #box3 {
    transition: 1s linear 0s;
}
#box2, #box4 {
    transition: 1s linear 0.5s;
}
#box5, #box7 {
    transition: 1s linear 1s;
}
#box6, #box8 {
    transition: 1s linear 1.5s;
}

#box0 {
    transition: 1s linear 0s;
    opacity: 1;
    width: 60px;
    height: 60px;
    background-color: #f2c018;
}


#box0:hover ~ #box1 {
    left: 0;
    top: 0;
}
#box0:hover ~ #box2 {
    left: 100%;
    top: 0%;
}
#box0:hover ~ #box3 {
    left: 0;
    top: 100%;
}
#box0:hover ~ #box4 {
    left: 100%;
    top: 100%;
}
#box0:hover ~ #box5 {
    left: 0;
    top: 50%;
}
#box0:hover ~ #box6 {
    left: 100%;
    top: 50%;
}
#box0:hover ~ #box7 {
    left: 50%;
    top: 0%;
}
#box0:hover ~ #box8 {
    left: 50%;
    top: 100%;
}

#box0:hover {
    opacity: 0;
}