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CSS

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HTML 

              
                <main class="max-w-3xl mx-auto my-8 pb-4 pl-4 border-l-8 border-l-teal-600">
  <h2 class="text-2xl font-medium text-amber-800">Useful</h2>
  <h1 class="mb-1 text-4xl font-light text-teal-800">Variables in Style Attribute</h1>
  <p class="font-medium">Recently, I came across some HTML code that looked like this: <code>&lt;span style="--w: .5"&gt;...&lt;/span&gt;</code>. 
  I had never seen (or thought of) setting CSS variables in an element's style attribute.  This pen explores some examples of this.
  </p>  
  
  <div class="boxset my-12 border-y-2 border-slate-200 p-4 w-full h-[16vw]">
    <div class="box" style="--t: 10; --l: 20"></div>
    <div class="box" style="--t: 20; --l: 40"></div>
    <div class="box" style="--t: 30; --l: 60"></div>
    <div class="box" style="--t: 40; --l: 80"></div>
  </div>
  
    <div class="boxset my-12 border-y-2 border-slate-200 p-4 w-full">
      <h3 class="font-bold text-amber-500">Ordered by Importance</h3>
      <div class="ordered">
        <div class="bar" style="--importance: 2">Apples</div>
        <div class="bar" style="--importance: 1">Bananas</div>
        <div class="bar" style="--importance: 4">Cherries</div>
        <div class="bar" style="--importance: 3">Dates</div>   
      </div>
      <h3 class="font-bold text-amber-500">Relative Importance</h3>
      <div class="chart">
        <div class="bar" style="--importance: 2">Apples</div>
        <div class="bar" style="--importance: 1">Bananas</div>
        <div class="bar" style="--importance: 4">Cherries</div>
        <div class="bar" style="--importance: 3">Dates</div>   
      </div>
  </div>
  
  <div class="boxset my-12 border-y-2 border-slate-200 p-4 w-full flex flex-wrap gap-4">
    <div class="veg" style="--color: green">
      <div class="name">Asparagus</div>
      <div class="desc">Stems</div>
    </div>
    <div class="veg" style="--color: red">
      <div class="name">Beetroot</div>
      <div class="desc">Roots</div>
    </div>
    <div class="veg" style="--color: mediumpurple">
      <div class="name">Cabbage</div>
      <div class="desc">Leaves</div>
    </div>
    <div class="veg" style="--color: orange">
      <div class="name">Carrots</div>
      <div class="desc">Roots</div>
    </div>
    <div class="veg" style="--color: yellow">
      <div class="name">Chili Peppers</div>
      <div class="desc">Fruit</div>
    </div>
  </div>
  
  <div class="boxset my-12 border-y-2 border-slate-200 p-4 w-full flex flex-wrap gap-4">
    <div class="profile" style="--color: green; --url-avatar: url(https://i.pravatar.cc/150?u=jamie)">
      <div class="name"><span>Jamie S.</span></div>
    </div>
    <div class="profile" style="--color: red">
      <div class="name"><span>Besie B.</span></div>
    </div>
    <div class="profile" style="--color: mediumpurple; --url-avatar: url(https://i.pravatar.cc/150?u=calin)">
      <div class="name"><span>Calin K.</span></div>
    </div>
    <div class="profile" style="--color: orange;  --url-avatar: url(https://i.pravatar.cc/150?u=danny)">
      <div class="name"><span>Danny D.</span></div>
    </div>
    <div class="profile" style=" --url-avatar: url(https://i.pravatar.cc/150?u=emily)">
      <div class="name">Emily M.</div>
    </div>
  </div>
  

  <div class="wrapper my-12 border-y-2 border-slate-200 p-4">
    
    <div class="sphere">
      <!-- default size and color -->
    </div>
    
    <div class="sphere" style="--size: 15cqw; --color: green">
      <!-- 15% of container width -->
    </div>
    
    <div class="sphere" style="--size: 15vw; --color: purple">
      <!-- 15% of viewport width -->
    </div>
    
    <div class="sphere" style="--size: 5rem; --color: yellow">
      <!-- 5x base font size -->
    </div>
    
    <div class="sphere" style="--size: 150px; --color: hotpink">
      <!-- static 150 pixels -->
    </div>
    
    <div class="sphere" style="--size: 30cqh; --color: olive">
      <!-- 30% of container's height -->
    </div>
    
    
  </div>
</main>
!

CSS 

              
                @import url('https://fonts.googleapis.com/css2?family=Lato:wght@100;300;400;700;900&display=swap');
html, body {
  font-family: "Lato", sans-serif;
  font-size: 20px;
}

.boxset {
  /* new stacking context */
  position: relative;
  z-index: 0;
  
  .box {
    position: absolute;
    top: calc(var(--t, 0) * 1%);
    left: calc(var(--l, 0) * 1%);
    width: 50px; height: 50px;
    background: slategray;
  }
  
  .ordered {
    display: flex;
    gap: 1rem;
    .bar {
      order: var(--importance, 100);  
    }
  }
  .chart {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    .bar {
      width: calc(100% - (var(--importance, 0%) * 10%));
      background: rgba(100,100,255, .1);
    }
  }
}

.veg {
  padding: 0.5rem;
  border: solid 1px var(--color, black);
  .name {
    color: hsl(from var(--color) h calc(s * .5) l);
  }
  .desc {
    font-size: 0.8rem;
    background-color: hsl(from var(--color) calc(h * .8) s l);
  }
}

.profile {
  --color: orchid;
  padding: 0.5rem;
  border: solid 1px var(--color, black);
  border-radius: 2rem;
  box-shadow: 1px 2px 6px hsl(from var(--color) h s 80%);
  .name {
    --size: 2rem;
    display: inline-flex;
    align-items: center;
    color: hsl(from var(--color) h s 20%);
    height: var(--size);
    &::before {
      content: '';
      display: inline-block;
      margin-right: 0.2rem;
      width: var(--size); height: var(--size);
      border-radius: 100%;
      background-color: hsl(from var(--color) h s 90%);
    }
  }
  &[style*='--url-avatar'] {
    .name::before {
      background-image: var(--url-avatar);
      background-repeat: none;
      background-size: cover;
    }
  }
}

.wrapper {
  /* new stacking context */
  position: relative;
  z-index: 0;
  
  /* flex it */
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 2rem;
  
  /* define container */
  container-name: wrapper;
  container-type: block-size;
  
  /* define the variables */
  --size: 10cqw;
  
  .sphere {
    display: inline-block;
    width: var(--size);
    height: var(--size);
    border: solid 1px gray;
    border-radius: 100%;
    
    --color: red;
    background: linear-gradient(-45deg,
      hsl(from var(--color) h calc(s * 6.5) l), 
      hsl(from var(--color) h calc(s * .5) l), 
      hsl(from var(--color) h s l),
      rgb(255,255,255),
      hsl(from var(--color) calc(h * 1.02) calc(s * 3) l)
    );
	  background-size: 400% 400%;
    
	  animation: sphereBG 15s ease infinite;
    
    box-shadow: 
      calc(var(--size) * .01) 
      calc(var(--size) * .01)
      calc(var(--size) * .1)
      hsl(from var(--color) h calc(s * 1.9) l);
  }
  
  
}


@keyframes sphereBG {
    0% {
		  background-position: 0% 50%;
	  }
	  50% {
		  background-position: 100% 50%;
	  }
	  100% {
		  background-position: 0% 50%;
	  }
  }
!

JS
!
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