// Customize

$option-color: #cbd1d8;

$checked-option-color: #40e0d0;

$option-size: 40px;

$explosion-distance: 5; // Multiplied by $option-size

$explosion-duration: 0.65s;

​

// On-click animation

@include keyframes(click-wave) {

  $offset: ((($option-size*$explosion-distance)-$option-size)/2);

  0% {

    @include size($option-size);

    opacity: 0.35;

    position: relative;

  }

  100% {

    @include size($option-size*$explosion-distance);

    margin-left: -$offset;

    margin-top: -$offset;

    opacity: 0.0;

  }

}

​

// Checkbox/Radio replacement

.option-input {

  @include appearance(none);

  @include position($option-size/3 0 0 0);

  @include size($option-size);

  @include transition;

  background: $option-color;

  border: none;

  color: #fff;

  cursor: pointer;

  display: inline-block;

  outline: none;

  position: relative;

  margin-right: 0.5rem;

  z-index: 1000;

​

  &:hover {

    background: darken($option-color, 15%);

  }

​

  &:checked {

    background: $checked-option-color;

​

    // The checkmark

    &::before {

      @include size($option-size);

      @include position(absolute);

      content: '\2716';

      display: inline-block;

      font-size: $option-size/1.5;

      text-align: center;

      line-height: $option-size;

    }

​

    // The "wave"

    &::after {

      @include animation(click-wave $explosion-duration);

      background: $checked-option-color;

      content: '';

      display: block;

      position: relative;

      z-index: 100;

    }

  }

  &.radio {

    border-radius: 50%;    

​

    &::after {

      border-radius: 50%;

    }

  }

}

​

// Demo styles

body {

  @include box(horizontal, start, stretch);

  background: #e8ebee;

  color: darken($option-color, 15%);

  font-family: $helvetica;

  text-align: center;

  div {

    padding: 5rem;

  }

​

  label {

    display: block;

    line-height: $option-size;

  }

}