main h2 {
    margin-bottom: 1.5em;
}

#intervalControl, #start span {
    min-width: 250px;
}

#square {
    width: 15vw;
    min-width: 300px;
    min-height: 300px;
    height: 15vw;
}

#square.active {
    background: rgb(244, 67, 54);
}

#avg {
    margin: 3em 0 2em;
}