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HTML 

              
                <div class="page-wrap">
  <div class="intro">
    <h1>Super Duper Expressive Color Attributes</h1>
    <p>Styling elements with <code class="bg">data-*</code> and way too many <code class="bg">~=</code> selectors. NSFProd.</p>
    <p class="answering-the-obvious"><strong>Q:</strong> But isn't this just a terrible idea?<br>
      <strong>A:</strong> ✋ Swerve.</p>
  </div>

  <div class="color-stuff">
    <div class="color">
      <div class="box" data-color="crimson"></div>
      <div class="descriptor"
           ><code><b>data-color</b> = <i>"crimson"</i></code></div>
    </div>
    <div class="color">
      <div class="box" data-color="blueish crimson"></div>
      <div class="descriptor">
        <code><b>data-color</b> = <i>"blueish crimson"</i></code>
      </div>
    </div>
    <div class="color">
      <div class="box" data-color="crimsonish blueish"></div>
      <div class="descriptor">
        <code><b>data-color</b> = <i>"crimsonish blueish"</i></code>
      </div>
    </div>
    <div class="color">
      <div class="box" data-color="crimsonish blue"></div>
      <div class="descriptor">
        <code><b>data-color</b> = <i>"crimsonish blue"</i></code>
      </div>
    </div>
    <div class="color">
      <div class="box" data-color="greenish cyanish"></div>
      <div class="descriptor">
        <code><b>data-color</b> = <i>"greenish cyanish"</i></code>
      </div>
    </div>
    <div class="color">
      <div class="box" data-color="greenish cyanish but not that green"></div>
      <div class="descriptor">
        <code><b>data-color</b> = <i>"greenish cyanish but not that green"</i></code>
      </div>
    </div>
    <div class="color">
      <div class="box" data-color="tomatoish pinkish but mostly tomato"></div>
      <div class="descriptor">
        <code><b>data-color</b> = <i>"tomatoish pinkish but mostly tomato"</i></code>
      </div>
    </div>
  </div>
</div>
!

CSS 

              
                // could of course add way more colors. I had all of the named colors to begin with but the SCSS processing was timing out and this is more than enough for a demo.
$colors: (crimson, red, pink, tomato, orange, yellow, purple, green, cyan, blue, brown, white, beige, silver, gray, black, magenta);

$length: length($colors);
@for $i from 1 to $length {
  [data-color~="#{nth($colors, $i)}"] {
    background: nth($colors, $i);
  }
  @for $j from ($i+1) through $length {
    
    // color 1 == color 2
    [data-color~="#{nth($colors, $i)}ish"][data-color~="#{nth($colors, $j)}ish"],
    [data-color~="#{nth($colors, $i)}"][data-color~="#{nth($colors, $j)}"]{
      background: mix(nth($colors, $i), nth($colors, $j));
    }
    
    // color 1 < color 2
    [data-color~="#{nth($colors, $i)}ish"][data-color~="#{nth($colors, $j)}ish"][data-color~="not"][data-color~="#{nth($colors, $i)}"],
    [data-color~="#{nth($colors, $i)}ish"][data-color~="#{nth($colors, $j)}ish"][data-color~="mostly"][data-color~="#{nth($colors, $j)}"],
    [data-color~="#{nth($colors, $i)}ish"][data-color~="#{nth($colors, $j)}"] {
      background: mix(nth($colors, $i), nth($colors, $j), 25%);
    }
    
    // color 1 > color 2
    [data-color~="#{nth($colors, $i)}ish"][data-color~="#{nth($colors, $j)}ish"][data-color~="not"][data-color~="#{nth($colors, $j)}"],
    [data-color~="#{nth($colors, $i)}ish"][data-color~="#{nth($colors, $j)}ish"][data-color~="mostly"][data-color~="#{nth($colors, $i)}"],
    [data-color~="#{nth($colors, $i)}"][data-color~="#{nth($colors, $j)}ish"] {
      background: mix(nth($colors, $i), nth($colors, $j), 75%);
    }
  }
}

// the last color is missed by the loops :(
[data-color~="#{nth($colors, $length)}"] {
  background: nth($colors, $length);
}

body {
  font-family: "Open Sans";
  color: #333;
  display: flex;
  background:  #ecf2f5;
}

.page-wrap {
  margin: 0 auto;
}

h1 {
  font-family: "Work Sans";
  margin-top: 40px;
  margin-bottom: 24px;
  color: #444;
}
code {
  font-family: "Space Mono";
  &.bg {
    background: #d3e3ea;
  }
  padding: 0 4px;
  border-radius: 2px;
  white-space: nowrap;
}

.intro {
  text-align: center;
  &:after {
    content: "";
    display: block;
    width: 128px;
    height: 3px;
    background: crimson;
    margin: 32px auto ;
  }
}

.color {
  display: flex;
  margin-bottom: 16px;
  &:last-of-type {
    margin-bottom: 40px;
  }
}

.box {
  height: 56px;
  width: 56px;
  float:left;
  margin-right: 16px;
  border-radius: 4px;
  box-shadow: 0 16px 24px -8px rgba(0, 0, 0, .1);
}

.descriptor {
  background: none;
  margin: auto 0;
}

.answering-the-obvious {
   &:before {
    content: "";
    display: block;
    width: 40px;
    height: 3px;
    background: #dfdfdf;
    margin: 24px auto ;
  }
}

.attr {
  color: crimson;
}
!

JS
!
999px

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