.slider {
    -webkit-appearance: none;
    appearance: none;
    margin-top: 1em;
    width: 50%;
    height: 0.2em;
    background: #cc8888;
    outline: none;
    opacity: 0.7;
    -webkit-transition: .2s;
    transition: opacity .2s;
}

.slider:hover {
    opacity: 1;
}

.slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 1.2em;
    height: 1.2em;
    border-radius: 50%;
    background: #cc8888;
    border: solid 4px #cc0000;
    cursor: pointer;
}

.slider::-moz-range-thumb {
    width: 1.5em;
    height: 1.5em;
    border-radius: 50%;
    background: #4CAF50;
    cursor: pointer;
}

.chart {
    width: 50%;
    margin-left: auto;
    margin-right: auto;
}