body {
    font-family: Arial, sans-serif;
    text-align: center;
    background: #f3f3f3;
}

.circuit-box {
    background: white;
    padding: 15px;
    width: 300px;
    margin: auto;
    border-radius: 8px;
    box-shadow: 0 0 8px gray;
}

.meters {
    margin-top: 30px;
    display: flex;
    justify-content: center;
    gap: 50px;
}

.meter {
    width: 120px;
    height: 60px;
    border: 3px solid black;
    border-radius: 120px 120px 0 0;
    position: relative;
    background: white;
}

.needle {
    width: 3px;
    height: 50px;
    background: red;
    position: absolute;
    bottom: 0;
    left: 50%;
    transform-origin: bottom center;
    transform: rotate(-90deg);
    transition: 0.4s;
}