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About the <head>

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!
Insecure Resource

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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="viewport" content="width=device-width"/>
<link href='https://fonts.googleapis.com/css?family=Give+You+Glory' rel='stylesheet' type='text/css'> 
</head>

<body>
<h2>Responsive UI with Ambient Light Events</h2>
<h1>Demo</h1>
<p>Sensor value:<br>
<span id="result">AmbientLightEvent is not supported</span></p>
    
<p>Sensor value in string:<br>
<span id="resultLevel">LightLevelEvent is not supported</span></p>

<p>
  <img src="http://placekitten.com/300/160"/>
</p>
  
  <p>I finally wrote up an article about this demo: <a href="http://girliemac.com/blog/2014/01/12/luminosity/">girliemac.com/blog/2014/01/12/luminosity/</a>
  </p>
<p>
  Kitty ipsum dolor sit amet, lay down in your way lay down in your way lick puking run, eat jump climb the curtains toss the mousie I don’t like that food eat. Zzz catnip sleep in the sink lay down in your way, claw zzz lay down in your way attack meow catnip. Knock over the lamp climb the curtains attack your ankles eat the grass, sniff climb the curtains fluffy fur judging you attack chuf chase the red dot.
</p>
<p>Kitty ipsum dolor sit amet, lay down in your way lay down in your way lick puking run, eat jump climb the curtains toss the mousie I don’t like that food eat. Zzz catnip sleep in the sink lay down in your way, claw zzz lay down in your way attack meow catnip. Knock over the lamp climb the curtains attack your ankles eat the grass, sniff climb the curtains fluffy fur judging you attack chuf chase the red dot.
</p>
  
  <p>
    Tail flick stuck in a tree lick sunbathe scratched attack your ankles, lick litter box litter box puking hiss. Attack zzz toss the mousie run climb the curtains, sleep on your keyboard litter box chase the red dot sleep in the sink lick zzz claw. Stuck in a tree kittens sleep on your keyboard lick run, knock over the lamp hiss zzz sleep on your keyboard feed me meow jump. Stretching catnip stuck in a tree scratched, run stuck in a tree stuck in a tree lick feed me sleep in the sink tail flick bat. Rip the couch scratched eat hiss, I don't like that food eat claw lay down in your way bat scratched climb the curtains biting. Puking stuck in a tree meow attack judging you, sleep in the sink give me fish stretching rip the couch purr fluffy fur.
  </p>
</body>
</html>
!

CSS 

              
                * {
	box-sizing: border-box;
}
html, input {
    font-family: "Segoe UI Web Light", "Segoe UI Light", "Segoe UI Web Regular", "Segoe UI", "HelveticaNeue-Light", "Helvetica Neue Light", "Helvetica Neue", Helvetica, Arial, "Lucida Grande", sans-serif; 
}
html {
    -ms-text-size-adjust: none;
}
html, body {
	padding: 0;
	margin: 1em;
	height: 100%;
}
body,
body.normal {
  /* default in mormal luminosity level */
  background-color: #d7d7d7;
  color: #111;
}
body.dim {
  background-color: #444;
  color: #fff;
}
body.bright {
  background-color: #fff;
  color: #333;
}
a {
	color: green;
}
header {
	margin-bottom: 1em;
}
h1, h2, h3 {
	margin: 0;
	font-weight: normal;
}
h1 {
	font-size: 3.375rem;
	text-transform: lowercase;
}
h2 {
	font-size: 1rem;
	text-transform: uppercase;
}

#result, #resultLevel {
  color: red;
}
!

JS 

              
                window.addEventListener('devicelight', function(e) {
  var lux = e.value;
  document.querySelector('#result').textContent = lux + ' lux';
  
  if(lux < 50) {
    document.body.className = 'dim';
  }
  if(lux >= 50 && lux <= 1000) {
    document.body.className = 'normal';
  }
  if(lux > 1000)  {
    document.body.className = 'bright';
  }
  
});

window.addEventListener('lightlevel', function(e) {
  var level = e.value; document.querySelector('#resultLevel').textContent = level;
  
  if(level === 'dim') {
    document.body.className = 'dim';
  }
  if(level === 'normal')  {
    document.body.className = 'normal';
  }
  if(level === 'bright')  {
    document.body.className = 'bright';
  }
});
!
999px

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