Automatic Image Slider with Pure CSS

A simple, CSS only, automatic image slider that makes use of CSS3 properties to move images from right to left.

How to use it:

Add a group of images into the slider.

<div class="slider">
  <ul class="slider__list">
    <li class="slider__slide"><img src="1.jpg" alt="Image 1" /></li>
    <li class="slider__slide"><img src="2.jpg" alt="Image 2" /></li>
    <li class="slider__slide"><img src="3.jpg" alt="Image 3" /></li>
    <li class="slider__slide"><img src="4.jpg" alt="Image 4" /></li>
  </ul>
</div>

Add a slider control to the webpage.

<input id="sliderSwitch" class="slider__switch" type="checkbox" name="sliderSwitch" hidden />
<div class="slider__control">
  <label for="sliderSwitch"></label>
</div>

Style the image slider.

.slider {
  position: relative;
  margin-top: 3rem;
  margin-right: auto;
  margin-left: auto;
  overflow: hidden;
  width: 40.625rem;
  height: 26.25rem;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}
.slider__list {
  position: absolute;
  left: 0;
  width: 162.5rem;
}
.slider__slide {
  float: left;
}

The CSS rules for the slider control.

.slider__control {
  margin-right: auto;
  margin-left: auto;
  width: 4.5rem;
  font-family: sans-serif;
}
.slider__control label {
  position: relative;
  display: block;
  margin-top: 2rem;
  margin-bottom: 1rem;
  width: 4.5rem;
  height: 2rem;
  font-size: 1rem;
  font-weight: normal;
  line-height: 1.5;
  color: transparent;
  background: #ddd;
  border-radius: 2rem;
  cursor: pointer;
  -webkit-transition: left 0.15s ease-out;
  transition: left 0.15s ease-out;
}
.slider__control label:before {
  content: "autoplay";
  position: absolute;
  top: 2.5rem;
  left: 0;
  color: #333;
 font-size: .95rem;
  font-weight: bold;
  text-transform: uppercase;
}
.slider__control label:after {
  content: "";
  position: absolute;
 top: .25rem;
 left: .25rem;
  display: block;
  width: 1.5rem;
  height: 1.5rem;
  border-radius: 2rem;
  background: #fff;
  -webkit-transition: left 0.15s ease-out;
  transition: left 0.15s ease-out;
  -webkit-transform: translate3d(0, 0, 0);
  transform: translate3d(0, 0, 0);
}
.slider__switch:checked + .slider > .slider__list {
  -webkit-animation-name: autoplay;
  animation-name: autoplay;
  /* This will change the time it takes to move to next slide */
  -webkit-animation-duration: 10s;
  animation-duration: 10s;
  -webkit-animation-iteration-count: infinite;
  animation-iteration-count: infinite;
}
.slider__switch:checked + .slider + .slider__control > label { background: #455a64; }
.slider__switch:checked + .slider + .slider__control > label:after { left: 2.75rem; }

Enable autoplay using CSS3 keyframes.

@-webkit-keyframes 
autoplay {   /* position of the first slide */
  0% {
 left: 0;
}
  /* position of the second slide */
  25% {
 left: -40.625rem;
}
  /* position of the third slide */
  50% {
 left: -81.25rem;
}
  /* position of the fourth slide */
  100% {
 left: -121.875rem;
}
}
@keyframes 
autoplay {   /* position of the first slide */
  0% {
 left: 0;
}
  /* position of the second slide */
  25% {
 left: -40.625rem;
}
  /* position of the third slide */
  50% {
 left: -81.25rem;
}
  /* position of the fourth slide */
  100% {
 left: -121.875rem;
}
}