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HTML

CSS

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JavaScript

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HTML

              
                <h1>H1 Heading</h1>
<h2>H2 Heading</h2>
<h3>H3 heading</h3>
<p>Here's a paragraph. Vivamus eget tristique ligula. Donec lacus nisl, posuere ac molestie sed, maximus id metus. Nunc consectetur vitae odio sed dignissim. Duis mattis vehicula tellus vel blandit. Nunc ultrices, justo sit amet pharetra venenatis, nisi ex fringilla nisi, vel suscipit ligula orci at tellus. Aliquam lorem quam, vehicula quis tincidunt eu, aliquam sit amet ex. Pellentesque hendrerit ultricies gravida. Pellentesque et finibus massa, ut fermentum libero. In scelerisque erat dolor, sit amet luctus augue elementum id. Nullam feugiat, ligula quis rhoncus tincidunt, orci dolor fermentum lacus, eu commodo metus erat ac diam.</p>
              
            
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CSS

              
                @import "lesshat";

// This allows you to easily change 
// the font size across the entire site
// by only adjusting the @baseFontSize value

@baseFontSize: 10px; // changing this affects each element in your site (if you are using the mixin below)

// Font size mixin for LESS
.font-size(@sizeValue) {
  @remValue: @sizeValue;
  @pxValue: (@sizeValue * @baseFontSize);
  font-size: ~"@{pxValue}";
  font-size: ~"@{remValue}rem";
}

// Examples of using the mixin in your LESS file...
html {
  // set base font size (all font-size declarations are rem so they point to this)
  font-size: @baseFontSize;
  -webkit-text-size-adjust: auto;
  -ms-text-size-adjust: @baseFontSize;
}

body {
  .font-size(1.9); // 19px if @baseFontSize is 10px
}
h1 { .font-size(3.2); }
h2 { .font-size(2.6); }
h3 { .font-size(2.2); }
              
            
!

JS

              
                
              
            
!
999px

Console