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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

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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 

              
                <div id="time-container">
  <h2>Time as Color</h2>
  <p class="description">See any time as a color or auto-localize to your current time. To learn more about this project, check out the details.</p>
  <div id="settings">
    <input id="military-time-toggle" type="checkbox"/>
    <label for="military-time-toggle">Military Time</label>
    <div id="time-holder">
      <select id="hours"></select>
      <select id="minutes"></select>
      <select id="seconds"></select>
      <select id="am-pm" class="visible">
        <option id="time-of-day-am">AM</option>
        <option id="time-of-day-pm">PM</option>
      </select>
    </div>
    <button id="use-my-time">Use My Current Time</button>
  </div>
</div>
!

CSS 

              
                :root {
  --background-color: #000000;
}

html, body {
  margin: 0;
  height: 100%;
}

body {
  background-color: var(--background-color);
  transition: 0.2s;
}

#time-container {
  background-color: white;
  padding: 1.25rem;
  border-radius: 6px;
  position: absolute;
  max-width: 40vw;
  top: 50%;
  left: 50%;
  transform: translate3d(-50%, -50%, 0);
  h2 {
    color: white;
    margin: 0 auto 1rem;
    $text-shadow: 1px 1px var(--background-color);
    @for $i from 2 to 10 {
      $text-shadow: $text-shadow, #{$i}px #{$i}px var(--background-color);
    }
    text-shadow: $text-shadow;
  }
}

.description, label {
  font-family: sans-serif;
  font-size: 0.9rem;
  letter-spacing: 0.2px;
  line-height: 1.2rem;
}

[type="checkbox"] {
  display: none;
  + label {
    margin-bottom: 0.5rem;
    display: inline-block;
    &::before {
      content: '';
      display: inline-block;
      width: 0.6rem;
      height: 0.6rem;
      border-radius: 2px;
      border: 1px solid var(--background-color);
      margin-right: 0.4rem;
      transition: 0.2s;
    }
    &:hover {
      cursor: pointer;
    }
  }
  &:checked + label::before {
    background-color: var(--background-color);
    box-shadow: 0 0 0 1px white inset;
  }
}

#am-pm {
  display: none;
  &.visible {
    display: initial;
  }
}

button {
  border: 0.5px solid var(--background-color);
  color: var(--background-color);
  padding: 0.4rem;
  font-size: 0.9rem;
  transition: 0.1s;
  margin-top: 1rem;
  &:hover {
    cursor: pointer;
    background-color: var(--background-color);
    color: white;
  }
}
!

JS 

              
                function recursivelyAddOption(start, amt, cont){
  var container = document.getElementById(cont);
  container.innerHTML = '';
  for(var i = start; i <= amt; i++){
    var opt = document.createElement('option');
    opt.id = cont + '-' + i;
    opt.textContent = i.toString().length === 1 && cont !== 'hours' ? '0' + i.toString() : i;
    container.appendChild(opt);
  }
}

function getMaximumValue(id){
  var opts = document.getElementById(id).querySelectorAll('option');
  var select_vals = Array.prototype.map.call(opts, function(elm){
    return parseInt(elm.value);
  });
  return select_vals.sort(function(a, b){ return a - b })[select_vals.length - 1];
}

function convertTimeToRGB(value, id){
  return value * 255 / getMaximumValue(id);
}

window.onload = function(){
  recursivelyAddOption(1, 12, 'hours');
  recursivelyAddOption(0, 59, 'minutes');
  recursivelyAddOption(0, 59, 'seconds');
  var select_elms = document.querySelectorAll('select');
  document.getElementById('military-time-toggle').addEventListener('change', function(ev){
    var am_pm_elm = document.getElementById('am-pm');
    if(!ev.target.checked){
      recursivelyAddOption(1, 12, 'hours');
      am_pm_elm.className = 'visible';
    } else {
      recursivelyAddOption(0, 23, 'hours');
      am_pm_elm.className = '';
    }
  });
  Array.prototype.forEach.call(select_elms, function(elm){
    elm.addEventListener('change', function(ev){
      var hrs = parseInt(document.getElementById('hours').value);
      if(!document.getElementById('military-time-toggle').checked){
        console.log(document.getElementById('am-pm').value);
        hrs += document.getElementById('am-pm').value === 'PM' ? 12 : 0;
      } 
      var mins = parseInt(document.getElementById('minutes').value);
      var secs = parseInt(document.getElementById('seconds').value);
      document.documentElement.style.setProperty('--background-color', 'rgb(' + convertTimeToRGB(hrs, 'hours') + ',' + convertTimeToRGB(mins, 'minutes') + ',' + convertTimeToRGB(secs, 'seconds') + ')');
    });
  });
  
  document.getElementById('use-my-time').addEventListener('click', function(){
    var time = new Date();
    var hrs = time.getHours();
    if(!document.getElementById('military-time-toggle').checked){
      var am_pm = hrs > 12 ? 'PM' : 'AM';
      hrs -= hrs > 12 ? 12 : 0;
      document.getElementById('am-pm').value = am_pm;
    }
    var mins = time.getMinutes();
    var secs = time.getSeconds();
    document.getElementById('hours').value = hrs;
    document.getElementById('minutes').value = mins.toString().length === 1 ? '0' + mins.toString() : mins;
    document.getElementById('seconds').value = secs.toString().length === 1 ? '0' + secs.toString() : secs;
    document.documentElement.style.setProperty('--background-color', 'rgb(' + convertTimeToRGB(hrs, 'hours') + ',' + convertTimeToRGB(mins, 'minutes') + ',' + convertTimeToRGB(secs, 'seconds') + ')');
  });
}
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