div.bar {
    width: 75% !important;
    display: block;
    margin: 0 auto;
}
@media (min-width: 768px) {
    div.bar {
        margin-top: 50px;
        width: 50% !important;
    }
}

div.pie {
    width: 100% !important;
}
@media (min-width: 768px) {
    div.pie {
        width: 25% !important;
    }
}

div.pie:not(.hidden) {
    display: inline-block !important;
}

.hidden {
    display: none !important;
}

button {
    background-color: transparent;
    border: none;
    font-size: 75%;
    opacity: 0.5;
}

.buttons {
    position: fixed;
    top: 0;
    left: 0;
    display: inline-flex;
    background-color: #2c303a;
}

.button {
    display: inline-flex;
    align-items: center;
    vertical-align: middle;
    background-color: #444857;
    color: white;
    padding: 0.5rem;
}

.button:hover {
    cursor: pointer;
    background-color: #5a5f73;
}