☑️ Transform Toggles, will-change ☑️

index.html

<div class="option-group">
  <div class="option-container">

    <input class="option-input" checked id="option-1" type="radio" name="options" />
    <input class="option-input" id="option-2" type="radio" name="options" />
    
    <label class="option" for="option-1">
      <span class="option__indicator"></span>
      <span class="option__label">
        1<sub>gb</sub>
      </span>
    </label>

    <label class="option" for="option-2">
      <span class="option__indicator"></span>
      <span class="option__label">
        5<sub>gb</sub>
      </span>
    </label>

  </div>
</div>
<div class="option-group">
  <div class="option-container">

    <input class="option-input" id="option-3" type="radio" name="options" />
    <input class="option-input" id="option-4" type="radio" name="options" />
    
    <label class="option" for="option-3">
      <span class="option__indicator"></span>
      <span class="option__label">
        10<sub>gb</sub>
      </span>
    </label>

    <label class="option" for="option-4">
      <span class="option__indicator"></span>
      <span class="option__label">
        20<sub>gb</sub>
      </span>
    </label>

  </div>
</div>

script.js

/* Nothing! */

scripts

<script src="//codepen.io/shshaw/pen/epmrgO"></script>

style.less

html {
  background: linear-gradient(to bottom, #4678F3, #64D6EE);
  font-size: 62.5%;
  height: 100%;
  display: flex; 
}
body { width: 100%; margin: auto; }

.option-group {
  width: 90%;
  max-width: 400px;
  height: 150px;
  position: relative;
  overflow: hidden;
  border-radius: 0.25em;
  font-size: 4rem;
  margin: 0.2em auto;
//  will-change: transform;
  transform: translateZ(0);
}

.option-container {
  display: flex; 
  justify-content: center;
  align-items: stretch;
  width: 120%;
  height: 100%;
  margin: 0 -10%;
}

.option {
  overflow: hidden;
  flex: 1;
  display: block;
  padding: 0.5em;
  background: #FFF;
  position: relative;
  margin: 0em;
  margin-right: 0.2em;
  &:last-child { margin-right: 0; }
  
  border-radius: 0.25em;
  
  display: flex;
  justify-content: flex-end;
  align-items: flex-start;
  flex-direction: column;
  
  cursor: pointer;
  
  opacity: 0.5;
  transition-duration: 0.8s, 0.6s;
  transition-property: transform, opacity;
  transition-timing-function: cubic-bezier(.98,0,.22,.98), linear;
  will-change: transform, opacity;
}

.option__indicator {
  display: block;
  transform-origin: left bottom;
  transition: inherit;
  will-change: transform;
  position: absolute;
  top: 0.5em;
  right: 0.5em;
  left: 0.5em;
  
  &:before,
  &:after {
    content: '';
    display: block;
    border: solid 2px #64D6EE;
    border-radius: 50%;
    width: 0.25em;
    height: 0.25em;
    position: absolute;
    top: 0;
    right: 0;
  }
  
  &:after {
    background: #64D6EE;
    transform: scale(0);
    transition: inherit;
    will-change: transform;
  }
}

.option-input {
  position: absolute;
  top: 0;
  z-index: -1;
  visibility: hidden;
}

.option__label {
  display: block;
  width: 100%;
  text-transform: uppercase;
  font-size: 1.5em;
  font-weight: bold;
  
  transform-origin: left bottom;
  transform: translateX(20%) scale(0.7);
  transition: inherit;
  will-change: transform;

  sub { 
    margin-left: 0.25em;
    font-size: 0.4em;
    display: inline-block; 
    vertical-align: 0.3em;
  }
  
  &:after {
    content: '';
    display: block;
    border: solid 2px #64D6EE;
    width: 100%;
    transform-origin: 0 0;
    transform: scaleX(0.2);
    transition: inherit;
    will-change: transform;
  }
}

.option:last-child {
  .option__label { transform: translateX(0%) scale(0.7); }
  .option__indicator { transform: translateX(-20%); }
}

.option-input:checked ~ .option {
  transform: translateX(-20%) translateX(0.2em);
  .option__indicator { transform: translateX(0%); }
  .option__label { transform: translateX(40%) scale(0.7); }
}

.option-input:first-child:checked ~ .option {
  transform: translateX(20%) translateX(-0.2em);
  .option__indicator { transform: translateX(-40%); }
  .option__label { transform: translateX(0%) scale(0.7); }
}

.option-input:nth-child(1):checked ~ .option:nth-of-type(1),
.option-input:nth-child(2):checked ~ .option:nth-of-type(2) {
  opacity: 1;
  .option__indicator { transform: translateX(0); &::after { transform: scale(1); } }
  .option__label,
  .option__label::after { transform: scale(1); }
}

transform-toggles-will-change.markdown

☑️ Transform Toggles, will-change ☑️

A transform-only version of Flexbox Toggles to compare performance and code. This takes it a little further with will-change for buttery-smooth animation without repaints.

Approximate recreation of https://cdn-images-1.medium.com/max/800/1*OIILijZ2MtrQ3br4FNjmOg.gif using only CSS.

A Pen by Matthew Daniel Brown on CodePen.

License.