Rainbow Range Slider | Learning Axis

HTML

CSS

body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background-color: #161616;
  padding: 0;
  margin: 0;
}

.range-wrapper {
  position: relative;
  z-index: 0;
  top: -0.6rem;
  height: 0.25rem;
}

.range-wrapper::before {
  content: "";
  position: absolute;
  top: -0.5rem;
  right: 0;
  width: calc(100% - var(--progress));
  height: 2rem;
  background: rgba(22, 22, 22, 0.7);
  border-radius: 999px;
}

.range-wrapper::after {
  content: "";
  position: absolute;
  top: 0.6rem;
  left: 0;
  z-index: -1;
  width: var(--progress);
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, #ff0000, #ff7700, #ffff00, #00ff00, #00ffff, #0000ff, #ff00ff);
  filter: blur(12px);
}

input[type="range"] {
  width: 20rem;
  height: 0.25rem;
  background-color: transparent;
  appearance: none;
  border-bottom: 2px solid #161616;
  border-radius: 999px;
}

input[type="range"]::-webkit-slider-runnable-track {
  border-radius: 999px;
  height: 0.25rem;
  background: linear-gradient(90deg, #ff0000, #ff7700, #ffff00, #00ff00, #00ffff, #0000ff, #ff00ff);
}

input[type="range"]::-webkit-slider-thumb {
  appearance: none;
  position: relative;
  z-index: 1;
  top: -0.4rem;
  width: 1rem;
  height: 1rem;
  border: 1px solid #161616;
  border-bottom: 2px solid #161616;
  border-radius: 50%;
  background: linear-gradient(90deg, #ff0000, #ff7700, #ffff00, #00ff00, #00ffff, #0000ff, #ff00ff);
  background-size: 10000% 100%;
  transition: box-shadow 0.5s ease;
  cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb:hover {
  box-shadow: 0 0 0.5rem rgba(255, 255, 255, 0.8);
}