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HTML

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Insecure Resource

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CSS

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CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.

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CSS Base

About CSS Base

It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.

Vendor Prefixing

About Vendor Prefixing

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <div class="container">
  <section class="column typo">
    Font Sizes
    <hr>
    <span class="text-1">size-1</span>
    <span class="text-2">size-2</span>
    <span class="text-3">size-3</span>
    <span class="text-4">size-4</span>
    <span class="text-5">size-5</span>
    <span class="text-6">size-6</span>
    <span class="text-7">size-7</span>
    <span class="text-8">size-8</span>
    <span class="text-9">size-9</span>
    <span class="text-10">size-10</span>
  </section>
  <section class="column">
    Spacing sizes
    <hr>
    <div class="look size-1">asdf</div>
    <div class="look size-2">asdf</div>
    <div class="look size-3">asdf</div>
    <div class="look size-4">asdf</div>
    <div class="look size-5">asdf</div>
    <div class="look size-6">asdf</div>
    <div class="look size-7">asdf</div>
    <div class="look size-8">asdf</div>
    <div class="look size-9">asdf</div>
    <span>root user stylesheet font size, default is 16px:</span>
    <div class="look size-10">asdf</div>
    <div class="look size-11">asdf</div>
    <div class="look size-12">asdf</div>
    <div class="look size-13">asdf</div>
    <div class="look size-14">asdf</div>
    <div class="look size-15">asdf</div>
    <div class="look size-16">asdf</div>
    <div class="look size-17">asdf</div>
    <div class="look size-18">asdf</div>
    <div class="look size-19">asdf</div>
  </section>
</div>
!

CSS 

              
                
:root{
  font-family: sans-serif;
  --base: calc(1rem/4);
  --scaling-down: 0.5;
  --scaling-up: 1.225;
  --size-1:   var(--base);
  --size-2:   calc( var(--size-1) * var(--scaling-up));
  --size-3:   calc( var(--size-2) * var(--scaling-up));
  --size-4:   calc( var(--size-3) * var(--scaling-up));
  --size-5:   calc( var(--size-4) * var(--scaling-up));
  --size-6:   calc( var(--size-5) * var(--scaling-up));
  --size-7:   calc( var(--size-6) * var(--scaling-up));
  --size-8:   calc( var(--size-7) * var(--scaling-up));
  --size-9:   calc( var(--size-8) * var(--scaling-up));
  --size-10:  calc( var(--size-9) * var(--scaling-up) );
  --size-11:  calc( var(--size-10) * var(--scaling-up) );
  --size-12:  calc( var(--size-11) * var(--scaling-up) );
  --size-13:  calc( var(--size-12) * var(--scaling-up) );
  --size-14:  calc( var(--size-13) * var(--scaling-up) );
  --size-15:  calc( var(--size-14) * var(--scaling-up) );
  --size-16:  calc( var(--size-15) * var(--scaling-up) );
  --size-17:  calc( var(--size-16) * var(--scaling-up) );
  --size-18:  calc( var(--size-17) * var(--scaling-up) );
  --size-19:  calc( var(--size-18) * var(--scaling-up) );
}

* {
  // outline:1px dashed coral;
}

body{
 padding:40px;
}

span{display: block;}
div{border-bottom:1px solid white;}

.container{
  display: grid;
  gap: 4rem;
  grid-template-columns: repeat(2, 1fr);
}

.column{
  display: flex;
  flex-direction: column;
}

hr{
  width: 100%;
  height: 1px;
  border: 0;
  border-bottom: 1px solid #ddd;
}

.column span{
  padding: 4px;  
}

.typo{
  text-align: right;
}

.look{
  padding: 3px 0;
  border-radius: 3px;
  background-color:gold;
  color: rgba(0,0,0,.3);
}

.size-{
  &1 {width: var(--size-1); background-color:dodgerblue;}
  &2 {width: var(--size-2); }
  &3 {width: var(--size-3); }
  &4 {width: var(--size-4); }
  &5 {width: var(--size-5); }
  &6 {width: var(--size-6); }
  &7 {width: var(--size-7); }
  &8 {width: var(--size-8); }
  &9 {width: var(--size-9); }
  &10{width: var(--size-10);background-color:dodgerblue;}
  &11{width: var(--size-11);}
  &12{width: var(--size-12);}
  &13{width: var(--size-13);}
  &14{width: var(--size-14);}
  &15{width: var(--size-15);}
  &16{width: var(--size-16);}
  &17{width: var(--size-17);}
  &18{width: var(--size-18);}
  &19{width: var(--size-19);}
}

.text-{
  &1 {font-size: var(--base) ;}
  &2 {font-size: var(--size-11) ;}
  &3 {font-size: var(--size-12) ;}
  &4 {font-size: var(--size-13) ;}
  &5 {font-size: var(--size-14) ;}
  &6 {font-size: var(--size-15) ;}
  &7 {font-size: var(--size-16) ;}
  &8 {font-size: var(--size-17) ;}
  &9 {font-size: var(--size-18) ;}
  &10 {font-size: var(--size-19) ;}
}
!

JS 

              
                const text1 = document.querySelector('.text-1');
const text2 = document.querySelector('.text-2');
const text3 = document.querySelector('.text-3');
const text4 = document.querySelector('.text-4');
const text5 = document.querySelector('.text-5');
const text6 = document.querySelector('.text-6');
const text7 = document.querySelector('.text-7');
const text8 = document.querySelector('.text-8');
const text9 = document.querySelector('.text-9');
const text10 = document.querySelector('.text-10');

const style1 = getComputedStyle(text1);
const style2 = getComputedStyle(text2);
const style3 = getComputedStyle(text3);
const style4 = getComputedStyle(text4);
const style5 = getComputedStyle(text5);
const style6 = getComputedStyle(text6);
const style7 = getComputedStyle(text7);
const style8 = getComputedStyle(text8);
const style9 = getComputedStyle(text9);
const style10 = getComputedStyle(text10);

text1.innerHTML = style1.fontSize;
text2.innerHTML = style2.fontSize;
text3.innerHTML = style3.fontSize;
text4.innerHTML = style4.fontSize;
text5.innerHTML = style5.fontSize;
text6.innerHTML = style6.fontSize;
text7.innerHTML = style7.fontSize;
text8.innerHTML = style8.fontSize;
text9.innerHTML = style9.fontSize;
text10.innerHTML = style10.fontSize;

// spacing sizes 

const size1 = document.querySelector('.size-1');
const size2 = document.querySelector('.size-2');
const size3 = document.querySelector('.size-3');
const size4 = document.querySelector('.size-4');
const size5 = document.querySelector('.size-5');
const size6 = document.querySelector('.size-6');
const size7 = document.querySelector('.size-7');
const size8 = document.querySelector('.size-8');
const size9 = document.querySelector('.size-9');
const size10 = document.querySelector('.size-10');
const size11 = document.querySelector('.size-11');
const size12 = document.querySelector('.size-12');
const size13 = document.querySelector('.size-13');
const size14 = document.querySelector('.size-14');
const size15 = document.querySelector('.size-15');
const size16 = document.querySelector('.size-16');
const size17 = document.querySelector('.size-17');
const size18 = document.querySelector('.size-18');
const size19 = document.querySelector('.size-19');

const sizeStyle1 = getComputedStyle(size1);
const sizeStyle2 = getComputedStyle(size2);
const sizeStyle3 = getComputedStyle(size3);
const sizeStyle4 = getComputedStyle(size4);
const sizeStyle5 = getComputedStyle(size5);
const sizeStyle6 = getComputedStyle(size6);
const sizeStyle7 = getComputedStyle(size7);
const sizeStyle8 = getComputedStyle(size8);
const sizeStyle9 = getComputedStyle(size9);
const sizeStyle10 = getComputedStyle(size10);
const sizeStyle11 = getComputedStyle(size11);
const sizeStyle12 = getComputedStyle(size12);
const sizeStyle13 = getComputedStyle(size13);
const sizeStyle14 = getComputedStyle(size14);
const sizeStyle15 = getComputedStyle(size15);
const sizeStyle16 = getComputedStyle(size16);
const sizeStyle17 = getComputedStyle(size17);
const sizeStyle18 = getComputedStyle(size18);
const sizeStyle19 = getComputedStyle(size19);

size1.innerHTML = sizeStyle1.width;
size2.innerHTML = sizeStyle2.width;
size3.innerHTML = sizeStyle3.width;
size4.innerHTML = sizeStyle4.width;
size5.innerHTML = sizeStyle5.width;
size6.innerHTML = sizeStyle6.width;
size7.innerHTML = sizeStyle7.width;
size8.innerHTML = sizeStyle8.width;
size9.innerHTML = sizeStyle9.width;
size10.innerHTML = sizeStyle10.width;
size11.innerHTML = sizeStyle11.width;
size12.innerHTML = sizeStyle12.width;
size13.innerHTML = sizeStyle13.width;
size14.innerHTML = sizeStyle14.width;
size15.innerHTML = sizeStyle15.width;
size16.innerHTML = sizeStyle16.width;
size17.innerHTML = sizeStyle17.width;
size18.innerHTML = sizeStyle18.width;
size19.innerHTML = sizeStyle19.width;
!
999px

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