body {
    background-color: black;
    color: white;
    text-align: center;
    user-select: none;
}

.circle {
    position: absolute;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    cursor: pointer;
}

.circle.selected {
    z-index: -1 !important;
    opacity: 0.7;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5);
}

.line {
    z-index: -1 !important;
    position: absolute;
    width: 4px;
    background-color: white;
    transform-origin: top left;
    border: 1px solid white;
}

.ring {
    z-index: -1; !important;
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    width: 70px;
    height: 70px;
    border-radius: 50%;
    border: 2px solid white;
}

#nextButton {
    position: absolute;
    bottom: 20px;
    right: 20px;
    transform: translateX(-50%);
    padding: 10px 20px;
    font-size: 16px;
    cursor: pointer;
}

#circle1 {
    background-color: blue;
}

#circle2 {
    background-color: red;
}

#circle3 {
    background-color: green;
}

#circle4 {
    background-color: yellow;
}

@media (max-width: 600px) {
    #nextButton {
        font-size: 14px;
        padding: 8px 16px;
        left: 50%;
        bottom: 10px;
    }
}