body {
    margin: 0;
    height: 100vh;
    transition: background 0.2s ease;
    display: flex;
    justify-content: center;
    align-items: center;
}
#bubble {
    position: absolute;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: white;
    z-index: 5;
}
#angle {
    font-size: 50px;
    font-family: Arial;
    color: white;
    z-index: 10;
}