.traffic-light {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    border: 1px solid #333;
    display: inline-block;
}

.traffic-light-red {
    background-color: #dc3545;
}

.traffic-light-yellow {
    background-color: #ffc107;
}

.traffic-light-green {
    background-color: #28a745;
}

.traffic-light-off {
    background-color: #6c757d;
    opacity: 0.3;
}
