CSS + HTML only Accordion Element

css-html-only-accordion-element.markdown

CSS + HTML only Accordion Element

Read the copy in the accordion sections for some info about how this was made.

A Pen by Ben Kremer on CodePen.

License.

index.html

<div class="centered">
  <ul>
    <li>
      <input type="checkbox" checked>
      <i></i>
      <h2>Toggle map</h2>
      <p><img src="http://lorempixel.com/400/200/" alt="placeholder"></p>
    </li>
  </ul>
</div>

style.sass

$white: rgba(254,255,250,1)
$grey: rgba(220,231,235,1)
$red: rgba(255,104,115,1)
$black: rgba(48,69,92,0.8)
$sans: 'Titillium Web', sans-serif
  
.transition
  transition: all 0.25s ease-in-out

.flipIn
  animation: flipdown 0.5s ease both
    
.no-select
  -webkit-tap-highlight-color: rgba(0,0,0,0)
  -webkit-touch-callout: none
  -webkit-user-select: none
  -khtml-user-select: none
  -moz-user-select: none
  -ms-user-select: none
  user-select: none

html
  width: 100%
  height: 100%
  perspective: 900
  overflow-y: scroll
  background-color: $grey
  font-family: $sans
  color: $black
  
body
  min-height: 0
  /* display: inline-block */
  display: table
  position: relative
  margin: 10px auto
  box-shadow: 0 10px 0 0 $red inset
  background-color: $white
  max-width: 100%
  padding: 30px
  
  @media ( max-width:550px )
    box-sizing: border-box
    transform: translate( 0 , 0 )
    max-width: 100%
    min-height: 100%
    margin: 0
    left: 0

.centered
  margin: 0 auto
  position: relative
  text-align: center
  width: 400px

h2
  color: $red

  
h2
  font-size: 26px
  line-height: 34px
  font-weight: 300
  letter-spacing: 1px
  display: block
  background-color: $white
  margin: 0
  cursor: pointer
  @extend .no-select

p
  color: $black
  position: relative
  overflow: hidden
  max-height: 300px
  @extend .transition
  opacity: 1
  transform: translate( 0 , 0 )  
  margin-top: 14px
  z-index: 2
  
ul
  list-style: none
  perspective: 900
  padding: 0
  margin: 0
  
  li
    position: relative
    padding: 0
    margin: 0
    padding-bottom: 4px
    padding-top: 18px
    border-top: 1px dotted $grey
    @extend .flipIn
      
    &:nth-of-type(1)
      animation-delay: 0.5s
    
    &:nth-of-type(2)
      animation-delay: 0.75s
        
    &:nth-of-type(3)
      animation-delay: 1.0s
    
    &:last-of-type
      padding-bottom: 0
      
    i
      position: absolute
      transform: translate( -6px , 0 )
      margin-top: 16px
      right: 0
      
      &:before , &:after
        content: ""
        @extend .transition
        position: absolute
        background-color: $red
        width: 3px
        height: 9px
        
      &:before
        transform: translate( -2px , 0 ) rotate( 45deg )
          
      &:after
        transform: translate( 2px , 0 ) rotate( -45deg )
    
    input[type=checkbox]
      position: absolute
      cursor: pointer
      width: 100%
      height: 100%
      z-index: 1
      opacity: 0
      
      &:checked
        &~p
          margin-top: 0
          max-height: 0
          opacity: 0
          transform: translate( 0 , 50% )
            
        &~i
          &:before
            transform: translate( 2px , 0 ) rotate( 45deg )
          
          &:after
            transform: translate( -2px , 0 ) rotate( -45deg )

@keyframes flipdown
  0%
    opacity: 0
    transform-origin: top center
    transform: rotateX(-90deg)
  5%
    opacity: 1
  80%
    transform: rotateX(8deg)
  83%
    transform: rotateX(6deg)
  92%
    transform: rotateX(-3deg)
  100%
    transform-origin: top center
    transform: rotateX(0deg)