.c-compare {
    --h: 9;
    --m: 1rem 0;
    --w: 16;
    --thumb-bgc: red;
    --thumb-bgc-focus: hsla(0, 70%, 70%, 0.7);
    --thumb-w: 1rem;
    margin: var(--m);
    position: relative;
}

.c-compare::after {
    content: "";
    display: block;
    padding-bottom: calc((var(--h) / var(--w)) * 100%);
}

.c-compare__left,
.c-compare__right {
    height: 100%;
    object-fit: cover;
    position: absolute;
    width: 100%;
}

.c-compare__left {
    clip-path: polygon(0% 0%, var(--value) 0%, var(--value) 100%, 0% 100%);
}

.c-compare__right {
    clip-path: polygon(100% 0%, var(--value) 0%, var(--value) 100%, 100% 100%);
}

.c-compare__range {
    background-color: transparent;
    box-sizing: border-box;
    font-family: inherit;
    height: 100%;
    margin: 0;
    outline: none;
    position: absolute;
    top: 0;
    width: 100%;
}

.c-compare__range::-moz-range-thumb {
    background-color: var(--thumb-bgc);
    cursor: ew-resize;
    height: 100%;
    width: var(--thumb-w);
}

.c-compare__range::-webkit-slider-thumb {
    background-color: var(--thumb-bgc);
    cursor: ew-resize;
    height: 100%;
    width: var(--thumb-w);
}

.c-compare__range:focus::-webkit-slider-thumb {
    background-color: var(--thumb-bgc-focus);
    box-shadow: 0 0 0 3px var(--thumb-bgc);
}

.c-compare__range:focus::-moz-range-thumb {
    background-color: var(--thumb-bgc-focus);
    box-shadow: 0 0 0 3px var(--thumb-bgc);
}

.c-compare__range::-moz-range-track {
    background: transparent;
    background-size: 100%;
    box-sizing: border-box;
}

.c-compare__range::-webkit-slider-runnable-track {
    background: transparent;
    background-size: 100%;
    box-sizing: border-box;
    height: 100%;
}

.c-compare__range,
.c-compare__range::-webkit-slider-runnable-track,
.c-compare__range::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
}


/* For demo */

body {
    font-family: ui-sansserif, system-ui, sans-serif;
    color: silver;
    margin: 0 auto;
    padding: 1rem;
    max-width: 1000px;
}