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HTML

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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

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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 

              
                <body>
  <h1>JavaScript Clock</h1>

  <div id="clock">
    <div id="time" class="glow"></div>

    <div id="date">
      <span class="month"></span>
      <span class="day"></span>,
      <span class="year"></span>
    </div>

    <div class="container">
      <button id="twelveHourBtn">24 hour clock</button>
    </div>
  </div>

  <div class="container">
    <ul id="days">
      <li class="sunday">Sun</li>
      <li class="monday">Mon</li>
      <li class="tuesday">Tues</li>
      <li class="wednesday">Wed</li>
      <li class="thursday">Thurs</li>
      <li class="friday">Fri</li>
      <li class="saturday">Sat</li>
    </ul>
  </div>

</body>
!

CSS 

              
                body, html {
  background: #000;
  color: #FFF;
  text-align: center;
  font-size: 16px;
  font-family: 'Orbitron', sans-serif;
}
h1 {
  visibility: hidden;
}
.container {
  display: block;
  margin: 1em auto;
}

#copyright {
  text-align: center;
  font-size: .8em;
  margin-top: 5em;
}
a{
  text-decoration: none;
}

a:visited{
  color: #555;
}
a:hover{
  color:#222;
}
button {
  background: #000;
  color: #FFF;
  text-transform: uppercase;
  width: 200px;
  height: 50px;
  border: none;
  outline: none;
}

button:hover {
  color: #444;
  transition: color .5s;
  cursor: pointer;
}
#time {
  font-size: 5em;
  margin: 3em 0 .5em;
}

#date {
  font-size: 2em;
  margin-bottom: 1em;
}
ul {
  font-size: 1.5em;
  color: #333;
}
ul li{
  margin: 1em;
  display: inline-block;
}
.glow {
  color: #fff;
  text-align: center;
  -webkit-animation: glow 1s ease-in-out infinite alternate;
  -moz-animation: glow 1s ease-in-out infinite alternate;
  animation: glow 1s ease-in-out infinite alternate;
}

@-webkit-keyframes glow {
  from {
    text-shadow: 0 0 10px #fff, 0 0 20px #fff, 0 0 30px #e50022, 0 0 40px #e50022, 0 0 50px #e50022, 0 0 60px #e50022, 0 0 70px #e50022;
  }

  to {
    text-shadow: 0 0 20px #fff, 0 0 30px #e20000, 0 0 40px #e20000, 0 0 50px #e20000, 0 0 60px #e20000, 0 0 70px #e20000, 0 0 80px #e20000;
  }
}
!

JS 

              
                const switchBtn = document.getElementById("twelveHourBtn");

let twelveHourBtn = document.getElementById("twelveHourBtn");
let getTime = document.getElementById("time");
let isTwelveHour = true;
let amPm = " AM";

// ============ Get the time ======================

function checkTime(i) {
  if (i < 10) {
    i = "0" + i;
  }
  return i;
}

function startTime() {
  let hours = "12";
  let today = new Date();
  let h = today.getHours();

  if (h > 12) {
    amPm = " PM";
  } else {
    amPm = " AM";
  }

  if (isTwelveHour) {
    hours = "24";
    if (h >= 12) {
      h = h - 12;
    }
  } else {
    hours = "12";
  }
  twelveHourBtn.innerHTML = hours + " hour clock";
  let m = today.getMinutes();
  let s = today.getSeconds();
  // add a zero in front of numbers<10
  m = checkTime(m);
  s = checkTime(s);
  getTime.innerHTML = h + ":" + m + ":" + s + amPm;
  t = setTimeout(function() {
    startTime();
  }, 500);
}

startTime();

switchBtn.addEventListener("click", function(e) {
  isTwelveHour = !isTwelveHour;
});

// ============= Get the day of the week =============================
switch (new Date().getDay()) {
  case 0:
    document.querySelector(".sunday").classList.add("glow");
    break;
  case 1:
    document.querySelector(".monday").classList.add("glow");
    break;
  case 2:
    document.querySelector(".tuesday").classList.add("glow");
    break;
  case 3:
    document.querySelector(".wednesday").classList.add("glow");
    break;
  case 4:
    document.querySelector(".thursday").classList.add("glow");
    break;
  case 5:
    document.querySelector(".friday").classList.add("glow");
    break;
  case 6:
    document.querySelector(".saturday").classList.add("glow");
}

// ============= Get the date =============================
let month = document.querySelector(".month");
let day = document.querySelector(".day");
let year = document.querySelector(".year");
let date = new Date();

let months = [
  "January",
  "February",
  "March",
  "April",
  "May",
  "June",
  "July",
  "August",
  "September",
  "October",
  "November",
  "December"
];
month.innerHTML = months[date.getMonth()];
day.innerHTML = date.getDate();
year.innerHTML = date.getFullYear();
!
999px

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