body{
    margin:0;
    padding:0;
    height:100vh;
    display:flex;
    justify-content:center;
    align-items:center;
    background:linear-gradient(135deg,#0f2027,#203a43,#2c5364);
    font-family:Arial, Helvetica, sans-serif;
}

.container{
    text-align:center;
}

h1{
    color:white;
    margin-bottom:20px;
}

#clock{
    font-size:70px;
    color:#00ffcc;
    letter-spacing:5px;

    padding:20px 40px;
    border-radius:10px;

    background:rgba(0,0,0,0.5);

    box-shadow:
    0 0 10px #00ffcc,
    0 0 20px #00ffcc,
    0 0 40px #00ffcc,
    0 0 80px #00ffcc;

    animation: glow 1.5s infinite alternate;
}

@keyframes glow{
    from{
        box-shadow:
        0 0 10px #00ffcc,
        0 0 20px #00ffcc,
        0 0 40px #00ffcc;
    }

    to{
        box-shadow:
        0 0 20px #00ffcc,
        0 0 40px #00ffcc,
        0 0 80px #00ffcc;
    }
}