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HTML 

              
                <html lang="en">
<head>
<meta charset="utf-8">
<title>Mr. CSS Lion</title>
<link href="https://fonts.googleapis.com/css?family=Lato:400,700,400italic,700italic" rel="stylesheet" type="text/css">
</head>

<body>
    <div class="lion">
        <span class="mane">
            <span class="head">
                <span class="eye left"></span>
                <span class="eye right"></span>
                <span class="nose"></span>
            </span>
            <span class="ear left">
                <span class="inner"></span>
            </span>
            <span class="ear right">
                <span class="inner"></span>
            </span>
        </span>
        <span class="body">
            <span class="paw left"></span>
            <span class="paw right"></span>
            <span class="leg left"></span>
            <span class="leg right"></span>
        </span>
        <span class="tail">s</span>
    </div>

</body>
</html>
!

CSS 

              
                @import compass

// ============== { ('_') } ==============

// Let's make a lion with CSS and then animate him. Why? BECAUSE REASONS.

// I also thought I'd use Mr.Lion to show a few examples of why I love using Sass to write CSS (http://sass-lang.com/)

// I'm also using Compass (http://compass-style.org/) which goes along with Sass really well and saves you from writing all of the required vendor prefixes out. For example, instead of writing all the prefixes for border-radius you can just do @include border-radius(amount). Yay!

@import compass/reset
@import compass/css3

// ======================================
// Sass rocks because VARIABLES { ('_') }
// ======================================

// Let's define some colours for Mr. Lion. Sass is AWESOME for this, since you can re-use these colour names all over and not have to change them in a bunch of places if Mr.Lion decides he wants to dye his fur pink one day.

$tan: #f5cd88
$mane: #ed8641
$dkbrown: #604f31

// You can also use variables for other things, anything that you might want to repeat a lot or refer to in a way that's easy to see why you're using it. I'll use one for a common border style.

$border-oval: 50%

// ============================================
// Sass rocks because COLOUR FUNCTIONS { ('_') }
// ============================================

// Mr. Lion also has a few highlights and shaded areas. Sass has this very cool inbuilt function to lighten or darken colours to create new colours based on our existing colour variables. Shiny.

$tan-highlight: lighten($tan, 15%)
$mane-shade: darken($mane, 5%)

// ===================================
// Sass rocks because MIXINS { ('_') }
// ===================================

// If we find ourselves repeating a bunch of properties on multiple elements, we can put these in a mixin to save ourselves repetition when using them over and over. Mixins can also be passed arguments if we need to customise them further!

// For example, a good way to center absolutely positioned elements regardless of their width is to give them the below properties which we'll reuse as mixins.

@mixin center-element-x
    left: 50%
    @include transform(translateX(-50%))

@mixin center-element
    left: 50%
    top: 50%
    @include transform(translateX(-50%) translateY(-50%))

// ===================================
// Sass rocks because NESTING { ('_') }
// ===================================

// We can avoid so much of the usual repetition we get with writing CSS. W00t.

body
    font-family: 'Lato', sans-serif
    padding: 50px 0

.lion
    width: 250px
    height: 300px
    position: relative
    margin: 0 auto
    span
        position: absolute
    .head
        width: 140px
        height: 105px
        top: 50px
        z-index: 2
        background-color: $tan
        @include border-radius($border-oval)
        @include center-element-x
    .eye
        width: 15px
        height: 22px
        top: 30px
        z-index: 2
        background-color: $dkbrown
        border: solid 10px $tan-highlight
        @include border-radius($border-oval)
        // &.left in Sass is the equivalent of doing .eye.left to chain classes in CSS. Less to write! Yay!
        &.left
            left: 10px
        &.right
            right: 10px
        -webkit-animation: blink 8s infinite
    .nose
        width: 18px
        height: 12px
        top: 70px
        z-index: 2
        background-color: $dkbrown
        @include border-radius($border-oval)
        @include center-element-x   
    .mane
        width: 219px
        height: 180px
        top: 0
        z-index: 1
        background-color: $mane
        @include border-radius($border-oval)
        @include center-element-x
        -webkit-animation: head-tilt 6s infinite
        //Bottom of mane
        &:before
            content: ''
            display: block
            position: absolute
            width: 0
            height: 0
            bottom: -54px
            left: 60px
            color: $mane
            // You can also indent within properties in Sass to make things like 
            // border sides easier to write!
            border: 50px solid transparent
                top: 100px solid $mane
                bottom: 0 
            @include transform(scaleX(1.9))
        //Mane shading
        &:after
            content: ''
            display: block
            position: absolute
            width: 140px
            height: 105px
            bottom: 15px
            left: 40px
            background-color: $mane-shade
            @include border-radius($border-oval) 
    .ear
        // You can use variables within selectors too, where you might find yourself
        // repeating a value multiple times.
        $ear: 60px
        width: $ear
        height: $ear
        top: 18px
        z-index: 2
        background-color: $tan
        @include border-radius($ear)
        &.left
            left: -15px
            &:before
                left: 60px
                @include transform(scaleX(1.5) rotate(-20deg))
        &.right
            right: -15px
            &:before
                right: 120px
                top: -35px
                @include transform(scaleX(1.5) rotate(20deg))
        .inner
            // Another super-useful thing that Sass can do is calculations! :D
            // To make sure that Mr. Lion's inner ear always stays in proportion
            // with his outer ear, we could do this:
            $inner-ear: $ear * 0.66
            width: $inner-ear
            height: $inner-ear
            background-color: $tan-highlight
            @include border-radius($inner-ear)
            @include center-element
        // Mane fluff
        &:before
            content: ''
            position: absolute
            width: 0
            height: 0
            top: -30px
            color: $mane
            border: 15px solid transparent
                bottom: 30px solid $mane
                top: 0
            @include transform(scaleX(1.5))
    .body
        width: 120px
        height: 260px
        top: 30px
        background-color: $tan
        @include border-radius(40px)
        @include center-element-x
        // Belly
        &:after
            content: ''
            position: absolute
            width: 80px
            height: 200px
            left: 20px
            top: 40px
            background-color: $tan-highlight
            @include border-radius(40px)
    .tail
        font-size: 150px
        right: 0
        top: 160px
        color: $tan
        @include transform(rotate(20deg))
        -webkit-animation: sway 2s linear alternate infinite
        -webkit-transform-origin: 20px 80px
        &:after
            content: 'w'
            position: absolute
            top: 49px
            left: 43px
            font:
                size: 40px
                weight: 700
            color: $mane
            @include transform(rotate(110deg))
    .leg
        width: 50px
        height: 100px
        bottom: -30px
        z-index: -1
        background-color: $tan
        @include border-radius(15px)
        &.left
            left: 0
        &.right
            right: 0
        &:after
            content: 'm'
            display: block
            position: absolute
            font-size: 30px
            bottom: -3px
            color: $tan-highlight
            @include center-element-x
    .paw
        width: 60px
        height: 35px
        top: 133px
        background-color: $tan
        @include border-radius(15px)
        &.left
            left: -35px
            &:after
                left: 5px
        &.right
            right: -35px
            &:after
                right: 5px
            -webkit-animation: wave 0.5s 5s linear 3
        //inner paw
        &:after
            $paw: 20px
            content: ''
            display: block
            position: absolute
            top: 7px
            width: $paw
            height: $paw
            background-color: $tan-highlight
            @include border-radius($paw)


// ============================================
// Animations for Mr. Lion { ('_') }
// ============================================
@-webkit-keyframes sway
    from
        @include transform(rotate(20deg))
    to
        @include transform(rotate(40deg))

@-webkit-keyframes head-tilt
    0%
        @include transform(translateX(-50%) rotate(0deg))
    50%
        @include transform(translateX(-50%) rotate(-5deg))
    0%
        @include transform(translateX(-50%) rotate(0deg))

@-webkit-keyframes blink
    0%
        @include transform(scaleY(1))
    50%
        @include transform(scaleY(1))
    51%
        @include transform(scaleY(0.1))
    52%
        @include transform(scaleY(1))
    100%
        @include transform(scaleY(1))

@-webkit-keyframes wave
    0%
        @include transform(rotate(0deg))
    50%
        @include transform(rotate(-30deg))
    100%
        @include transform(rotate(0deg))
!

JS
!
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