body {
    box-sizing: border-box;
    background-color: aliceblue;
    margin: 100px;
}

h1 {
    text-align: center;
    color: #000;
    font-size: 3em;
    margin-bottom: 90px;
}
#hoursOutput {
    font-size: 4em;
    color: #fff;
    background-color: darkgoldenrod;
    padding: 10px;
    border-radius: 10px;
    margin-top: 10px;
    text-align: center;
}

#minutesOutput {
    font-size: 3em;
    color: #fff;
    background-color: orange;
    padding: 10px;
    border-radius: 10px;
    margin-top: 10px;
    text-align: center;
}
#secondsOutput {
    font-size: 2em;
    color: #000;
    background-color: greenyellow;
    padding: 10px;
    border-radius: 10px;
    margin-top: 10px;
    text-align: center;
}