:root {
  --sliderSwitchWidth: 30px;
  --sliderBeforeWidthHeight: calc(var(--sliderSwitchWidth) * (13 / 30));
  --sliderBeforeLR: calc(var(--sliderSwitchWidth) * (1 / 15));
}

body {
  text-align: center;
}
.hidden {
  display: none;
}

.redText {
	color: red;
}

.blackText {
  color: black;
}


/* The switch - the box around the slider */
.switch {
  position: relative;
  display: inline-block;
  width: var(--sliderSwitchWidth);
  height: calc(var(--sliderSwitchWidth) * (17 / 30));
}

/* Hide default HTML checkbox */
.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

/* The slider */
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ccc;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}

.slider:before {
  position: absolute;
  content: "";
  height: var(--sliderBeforeWidthHeight);
  width: var(--sliderBeforeWidthHeight);
  left: var(--sliderBeforeLR);
  bottom: var(--sliderBeforeLR);
  background-color: white;
  -webkit-transition: 0.4s;
  transition: 0.4s;
}

input:checked + .slider {
  background-color: #2196f3;
}

input:focus + .slider {
  box-shadow: 0 0 1px #2196f3;
}

input:checked + .slider:before {
  -webkit-transform: translateX(var(--sliderBeforeWidthHeight));
  -ms-transform: translateX(var(--sliderBeforeWidthHeight));
  transform: translateX(var(--sliderBeforeWidthHeight));
}

/* Rounded sliders */
.slider.round {
  border-radius: 34px;
}

.slider.round:before {
  border-radius: 50%;
}