* {
  margin: 0;
  padding: 0;
  border: none;
  -webkit-tap-highlight-color: transparent;
}

:root {
  --slider-width: 50rem;
  --slider-height: 30rem;
}

html,
body {
  height: 100%;
}
h1 { color: #fff; }
body {
  display: flex;
  align-items: center;
  justify-content: center;

  background: #121212;
}

.compare {
  position: relative;
  height: var(--slider-height);
  width: var(--slider-width);
}

.compare__slider {
  position: absolute;
  z-index: 1;
  width: 3.6rem;
  height: 3.6rem;
  background: #121212;
  border: 0.1rem solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 0.2rem 0.8rem rgba(0, 0, 0, 0.8);
  border-radius: 50%;
  cursor: grab;
  transition: border-color 0.2s;
}

.compare__slider:active {
  border: 0.1rem solid rgba(255, 255, 255, 0.3);
  cursor: grabbing;
}

.compare__image {
  position: absolute;

  height: var(--slider-height);
  width: var(--slider-width);
  border-radius: 0.4rem;

  overflow: hidden;
  user-select: none;
  pointer-events: none;
}

.compare__image img {
  height: var(--slider-height);
  width: var(--slider-width);
  object-fit: cover;
}