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HTML

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HTML preprocessors can make writing HTML more powerful or convenient. For instance, Markdown is designed to be easier to write and read for text documents and you could write a loop in Pug.

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About the <head>

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!
Insecure Resource

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CSS

About CSS Preprocessors

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

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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HTML 

              
                <button type="button" id="large" class="btn btn-default btn-sm" data-mode="large">Large</button>
<button type="button" id="large" class="btn btn-default btn-sm" data-mode="medium">Medium</button>
<button type="button" id="small" class="btn btn-default btn-sm" data-mode="small">Small</button>

<div class="header">
  <div class="logo">
    <!-- 3kb SVG -->
    <svg viewBox="0 0 525.672 265.545">
      <path id="Mark" fill="#FFFFFF" d="M212.952,21.162l120.943,120.932h-51.106c0,0-88.332-88.342-95.39-95.392
        c-7.042-7.062-16.292-10.588-25.532-10.588c-9.238,0-18.501,3.525-25.551,10.588c-7.044,7.05-10.576,16.294-10.576,25.54
        s3.519,18.489,10.576,25.539c7.05,7.062,16.287,10.575,25.532,10.575c9.259,0,18.509-3.513,25.551-10.575l12.778,12.782
        l12.774,12.771c-14.11,14.086-32.595,21.149-51.104,21.149c-18.482,0-36.974-7.063-51.072-21.149
        C96.682,109.22,89.62,90.731,89.62,72.227c0-18.475,7.062-36.965,21.156-51.065C124.875,7.05,143.366,0,161.849,0
        C180.357,0,198.842,7.05,212.952,21.162 M299.317,5.358c-3.524-3.537-8.148-5.292-12.769-5.292c-4.637,0-9.247,1.755-12.785,5.292
        c-3.524,3.525-5.293,8.148-5.293,12.77c0,4.623,1.769,9.232,5.293,12.757l111.198,111.209h51.09L299.317,5.358z"/>
      <path id="Logotype" fill="#FFFFFF" d="M0,240.533v-0.156c0-13.828,10.354-25.164,25.081-25.164c8.967,0,14.396,3.139,19.057,7.594
        l-5.5,6.303c-3.887-3.619-8.071-6.033-13.616-6.033c-9.308,0-16.049,7.646-16.049,17.172v0.129c0,9.533,6.742,17.316,16.049,17.316
        c5.966,0,9.794-2.441,13.964-6.326l5.495,5.549c-5.067,5.297-10.625,8.629-19.743,8.629C10.561,265.545,0,254.492,0,240.533
         M84.204,215.705h7.928l21.401,49.014h-9.025l-4.94-11.752H76.56l-5.002,11.752h-8.761L84.204,215.705z M96.437,245.4l-8.418-19.471
        L79.691,245.4H96.437z M133.043,257.617l5.132-6.121c4.662,4.041,9.322,6.34,15.377,6.34c5.274,0,8.605-2.43,8.605-6.121v-0.129
        c0-3.5-1.938-5.373-10.981-7.438c-10.355-2.52-16.192-5.566-16.192-14.537v-0.143c0-8.34,6.948-14.104,16.619-14.104
        c7.088,0,12.717,2.146,17.65,6.109l-4.584,6.469c-4.377-3.279-8.768-4.996-13.209-4.996c-5.003,0-7.929,2.543-7.929,5.758v0.145
        c0,3.756,2.222,5.408,11.546,7.627c10.275,2.506,15.635,6.186,15.635,14.268v0.129c0,9.105-7.154,14.525-17.367,14.525
        C145.897,265.398,138.878,262.832,133.043,257.617 M199.938,216.053h36.082v7.643h-27.527v12.656h24.39v7.643h-24.39v13.076h27.87
        v7.648h-36.425V216.053z M290.277,216.053h9.116l14.797,23.021l14.811-23.021h9.103v48.666h-8.545v-34.914L314.19,252.76h-0.283
        l-15.223-22.789v34.748h-8.407V216.053z M382.906,215.705h7.928l21.409,49.014h-9.04l-4.931-11.752H375.25l-4.983,11.752h-8.769
        L382.906,215.705z M395.135,245.4l-8.407-19.471l-8.34,19.471H395.135z M440.353,223.98h-15.431v-7.928h39.497v7.928h-15.441v40.738
        h-8.625V223.98z M489.248,216.053h36.088v7.643h-27.538v12.656h24.403v7.643h-24.403v13.076h27.874v7.648h-36.424V216.053z
         M267.037,235.719h-9.516v9.527h9.516V235.719z"/>
    </svg>
  </div>
</div>
!

CSS 

              
                // [mode] attribute selection for demo purposes
// use media queries in production

.header {
  background: #000;
  height: 40px;
  
  &[mode='medium'] {
    height: 80px;
  }
  
  &[mode='large'] {
    height: 120px;
  }
}

.logo {
  height: 20px;
  width: 50px;
  
  [mode='medium'] & {
    height: 40px;
    width: 259px;
  }
  
  [mode='large'] & {
    height: 70px;
    width: 139px;
  }
}

#Logotype {
	[mode='small'] & {
		opacity: 0;
	}

	[mode='medium'] & {
		transform: scale(2.42) translate(0, -207px);
	}

	[mode='large'] & {
		transform: scale(1);
	}
}

#Mark {
	[mode='small'] & {
		transform: translate(-89px);
	}

	[mode='medium'] & {
		transform: translate(1266px);
	}
  
	[mode='large'] & {
		transform: translate(0);
	}
}
!

JS 

              
                var header     = document.querySelector('.header');
var logoSVG    = document.querySelector('.logo svg');
var viewbox    = logoSVG.getBBox();
var logoWidth  = Math.floor(viewbox.width * 1000) / 1000;
var logoHeight = Math.floor(viewbox.height * 1000) / 1000;

// values from Illustrator's info panel
var logoWidthMd  = 1702;
var logoHeightMd = 145;
var logoWidthSm  = 347;
var logoHeightSm = 145;

// setMode for demo purposes, use media queries in production
var setMode = function(mode) {
  header.setAttribute('mode', mode);
};

// setViewbox for matching viewBox to new size of paths
var setViewbox = function(w, h) {
  logoSVG.setAttribute('viewBox', '0 0 ' + w + ' ' + h);
}

// update logo size when crossing breakpoints
enquire
  .register("screen and (max-width: 499px)", function() {
    setViewbox(logoWidthSm, logoHeight);
    setMode('small');
  })
  .register("screen and (min-width: 500px)", function() {
    setViewbox(logoWidthMd, logoHeight);
    setMode('medium');
  })
  .register("screen and (min-width: 700px)", function() {
    setViewbox(logoWidth, logoHeight);
    setMode('large');
  });

// ==============================
// boilerplate demo code...
// ==============================
document.addEventListener('click', function(e) {
  if (e.target.type !== 'button') return;

  var mode = e.target.getAttribute('data-mode');
  setMode(mode);
  
  if (mode == 'small') {
    setViewbox(logoWidthSm, logoHeightSm);
  } else if (mode == 'medium') {
    setViewbox(logoWidthMd, logoHeightMd);
  } else {
    setViewbox(logoWidth, logoHeight);
  }
});
!
999px

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