.bubbles-modulation-matrix {
    display: grid;
    grid-template-columns: 25% 25% 25% 25%;
    grid-template-rows: auto;
    padding-left: 1em;
}

.bubbles-modulator {
    color: #fff;
    font-family: sans-serif;
    font-size: 60%;
    font-weight: 700;
    padding: 0.5em;
    text-align: center;
}

.bubbles-modulator label {
    display: block;
}

.bubbles-modulator input {
    border: none;
    font-size: 100%;
    margin-top: 0.5em;
    padding: 0.5em;
    text-align: center;
    width: 50%;
}