* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

.switch-toggle {
  display: block;
  width: 100px;
  height: 40px;
  margin: 30px auto;
  background: gray;
  border-radius: 99px;
  position: relative;
  overflow: hidden;
}

.switch-toggle .switch-icon {
  display: block;
  height: 38px;
  width: 38px;
  background: #fff;
  border-radius: 50%;
  position: absolute;
  top: 1px;
  left: 1px;
  transition: left 0.4s ease;
  z-index: 1;
  cursor: pointer;
}
.switch-toggle .bg {
  content: "";
  display: block;
  position: absolute;
  inset: 0;
  transition: background 0.4s ease;
  cursor: pointer;
}
.switch-toggle input:checked ~ .switch-icon {
  left: calc(100% - 39px);
}

.switch-toggle input:checked ~ .bg {
  background: green;
}