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CSS

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JavaScript

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HTML 

              
                <!-- 2017 Countdown - Simple JS, HTML, & CSS only -->

<body>
  <div class="countdown" id="js-countdown">
    <div class="countdown__item countdown__item--large">
      <div class="countdown__timer js-countdown-days" aria-labelledby="day-countdown">
        
      </div>
      
      <div class="countdown__label" id="day-countdown">Days</div>
    </div>
    
    <div class="countdown__item">
      <div class="countdown__timer js-countdown-hours" aria-labelledby="hour-countdown">
        
      </div>
      
      <div class="countdown__label" id="hour-countdown">Hours</div>
    </div>
    
    <div class="countdown__item">
      <div class="countdown__timer js-countdown-minutes" aria-labelledby="minute-countdown">
        
      </div>
      
      <div class="countdown__label" id="minute-countdown">Minutes</div>
    </div>
    
    <div class="countdown__item">
      <div class="countdown__timer js-countdown-seconds" aria-labelledby="second-countdown">
        
      </div>
      
      <div class="countdown__label" id="second-countdown">Seconds</div>
    </div>
  </div>
</body>




<!-- 2013 Countdown -->
<!-- <body>
  <form class="countdown" name="countDown">
    <input size="4" name="daysLeft" />
    <hr class="soft">
    <h3>Days</h3>
    <hr class="soft">
    <span class="bottom_time"><input size="3"  name="hrLeft" /></span>
    <span class="bottom_time"><input size="3"  name="minLeft" /></span>
    <span class="bottom_time"><input size="3"  name="secLeft" /></span>
    <ul>
      <li>Hrs</li>
      <li>Min</li>
      <li>Sec</li>
    </ul>
  </form>
</body> -->
!

CSS 

              
                // ========================== //
// 2017 Countdown CSS
// ========================== //

body {
  display: flex;
  align-items: center;
  min-height: 100vh;
  text-align: center;
  font-family: helvetica;
  text-transform: uppercase;
  background-image: linear-gradient(
    165deg, 
    rgba(194, 233, 221, 0.5) 3%,
    rgba(104, 119, 132, 0.5) 100%);
}

.countdown {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  width: 75%;
  max-width: 20rem;
  margin: 0 auto;
}

.countdown__item {
  display: flex;
  flex-direction: column;
  flex: 0 1 auto;
  min-width: 31%;
  margin-bottom: 1rem;

// Instead of a modifier one could use a pseudo-class:
//   &:first-child {
//     width: 100%;
//   }
  
//   &:not(:first-child) {
//     flex: 1;
//   }
}

.countdown__item--large {
  flex: auto;
  width: 100%;
  font-size: 2.75em;
}

.countdown__timer {
  padding: .25em;
  background-color: white;
  border: 1px solid black;
  border-radius: 3px;
  font-weight: bold;
  font-size: 2em;
}

.countdown__label {
  font-size: 1em;
  padding-top: .40em;
  
  .countdown__item--large & {
    &:before,
    &:after {
      content: '';
      display: block;
      height: 1px;
      background-image: linear-gradient(
        left,
        rgba(0, 0, 0, 0), 
        rgba(0, 0, 0, .4),
        rgba(0, 0, 0, 0));
    }

  }
}




// ========================== //
// 2013 Countdown CSS
// ========================== //

// @import "compass/css3";
// html {
//     height: 100%;
// }
// body {
//     display: flex;
//     align-items: center;
//     min-height: 100%;
//     background-image: linear-gradient(165deg, rgba(194, 233, 221, 0.5) 3%, rgba(104, 119, 132, 0.5) 100%);
//     text-align: center;
//     font-family: helvetica;
//     text-transform: uppercase;
// }
// .countdown {
//     position: relative;
//     top: 50%;
//     display: block;
//     height: auto;
//     max-width: 35em;
//     margin: 0 auto;
//     input {
//         text-transform: uppercase;
//         text-align: center;
//         font-family: helvetica;
//         height: 1.25em;
//         border: 1px solid black;
//         font-weight: 700;
//         font-size: 9.5rem;
//         width: 80%;
//         margin: 0 10px;
//         @include border-radius(5px);
//     }
//     h3 {
//         font-size: 5.0rem;
//         font-weight: 700;
//         letter-spacing: 5px;
//         margin: -30px;
//     }
//     .bottom_time input {
//         padding: 2.0% 4.1%;
//         display: inline-block;
//         height: 1em;
//         font-weight: 500;
//         font-size: 2.5rem;
//         color: black;
//         width: 15.5%;
//     }
//     ul {
//         padding: 0;
//         margin: .5em 0;
//         li {
//             display: inline;
//             font-weight: 500;
//             padding: 0 11%;
//         }
//     }
//     hr.soft {
//         height: 1px;
//         margin: 1.5em 0;
//         background-image: -webkit-gradient(linear, 0 0, 100% 0, from(rgba(0, 0, 0, 0)), color-stop(0.5, rgba(0, 0, 0, .4)), to(rgba(0, 0, 0, 0)));
//         background-image: -webkit-linear-gradient(left, rgba(0, 0, 0, 0), rgba(0, 0, 0, .4), rgba(0, 0, 0, 0));
//         background-image: -moz-linear-gradient(left, rgba(0, 0, 0, 0), rgba(0, 0, 0, .4), rgba(0, 0, 0, 0));
//         background-image: -o-linear-gradient(left, rgba(0, 0, 0, 0), rgba(0, 0, 0, .4), rgba(0, 0, 0, 0));
//         background-image: linear-gradient(left, rgba(0, 0, 0, 0), rgba(0, 0, 0, .4), rgba(0, 0, 0, 0));
//         border: 0;
//     }
// }
!

JS 

              
                // ========================== //
// 2017 Countdown JS
// ========================== //

const countdown = new Date("May 7, 2021");

function getRemainingTime(endtime) {
  const milliseconds = Date.parse(endtime) - Date.parse(new Date());
  const seconds = Math.floor( (milliseconds/1000) % 60 );
  const minutes = Math.floor( (milliseconds/1000/60) % 60 );
  const hours = Math.floor( (milliseconds/(1000*60*60)) % 24 );
  const days = Math.floor( milliseconds/(1000*60*60*24) );

  return {
    'total': milliseconds,
    'seconds': seconds,
    'minutes': minutes,
    'hours': hours,
    'days': days,
  };
}
  
function initClock(id, endtime) {
  const counter = document.getElementById(id);
  const daysItem = counter.querySelector('.js-countdown-days');
  const hoursItem = counter.querySelector('.js-countdown-hours');
  const minutesItem = counter.querySelector('.js-countdown-minutes');
  const secondsItem = counter.querySelector('.js-countdown-seconds');

  function updateClock() {
    const time = getRemainingTime(endtime);

    daysItem.innerHTML = time.days;
    hoursItem.innerHTML = ('0' + time.hours).slice(-2);
    minutesItem.innerHTML = ('0' + time.minutes).slice(-2);
    secondsItem.innerHTML = ('0' + time.seconds).slice(-2);

    if (time.total <= 0) {
      clearInterval(timeinterval);
    }
  }

  updateClock();
  const timeinterval = setInterval(updateClock, 1000);
}

initClock('js-countdown', countdown);




// ========================== //
// 2013 Countdown JS
// ========================== //

// function counter() {
//   var today = new Date(); //variable contains current date and time

//   var days = calcDays(today); //calculate the time left until set date below
//   document.countDown.daysLeft.value = Math.floor(days); // displays days rounded to the next lowest integer

//   var hours = (days - Math.floor(days)) * 24; //calculate the hours left in the current day
//   document.countDown.hrLeft.value = Math.floor(hours); // display hours rounded to the next lowest integer

//   var minutes = (hours - Math.floor(hours)) * 60; // calculate the minutes left in the current hour
//   document.countDown.minLeft.value = Math.floor(minutes); // display minutes rounded to the next lowest integer

//   var seconds = (minutes - Math.floor(minutes)) * 60; //calculate the seconds left in the current minute
//   document.countDown.secLeft.value = Math.floor(seconds); // display seconds rounded to the next lowest integer
// }

// function calcDays(currentDate) {
//   //create a date object for date of graduation
//   //calculate the difference between currentDate and set date
//   setDate = new Date("May 6, 2013");
//   currentTime = currentDate.getFullYear() + 1;
//   setDate.setFullYear(currentTime);

//   days = (setDate - currentDate) / (1000 * 60 * 60 * 24);
//   return days;
// }

// setInterval('counter()', 1000)
!
999px

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