JSFiddle - React, Tailwind, and code Playground

by Van Hai Le

HTML

<div class="clock">
      <div class="clock-face">
        <div class="hand hour-hand"></div>
        <div class="hand min-hand"></div>
        <div class="hand second-hand"></div>
      </div>
    </div>

CSS

html {
      background: #018DED url(http://unsplash.it/1500/1000?image=881&blur=50);
      background-size: cover;
      font-family: 'helvetica neue';
      text-align: center;
      font-size: 10px;
    }
    body {
      margin: 0;
      font-size: 2rem;
      display: flex;
      flex: 1;
      min-height: 100vh;
      align-items: center;
    }
    .clock {
      width: 30rem;
      height: 30rem;
      border: 20px solid white;
      border-radius: 50%;
      margin: 50px auto;
      position: relative;
      padding: 2rem;
      box-shadow:
        0 0 0 4px rgba(0,0,0,0.1),
        inset 0 0 0 3px #EFEFEF,
        inset 0 0 10px black,
        0 0 10px rgba(0,0,0,0.2);
    }
    .clock-face {
      position: relative;
      width: 100%;
      height: 100%;
      transform: translateY(-3px); /* account for the height of the clock hands */
    }
    .hand {
      width: 50%;
      height: 6px;
      background: black;
      position: absolute;
      top: 50%;
      transform-origin: 100%;
      transform: rotate(90deg);
      transition: all 0.05s;
      transition-timing-function: cubic-bezier(0.1, 2.7, 0.58, 1);
    }

JavaScript

const secondHand = document.querySelector('.second-hand');
  const minsHand = document.querySelector('.min-hand');
  const hourHand = document.querySelector('.hour-hand');
  function setDate() {
    const now = new Date();
    const seconds = now.getSeconds();
    const secondsDegrees = ((seconds / 60) * 360) + 90;
    secondHand.style.transform = `rotate(${secondsDegrees}deg)`;
    const mins = now.getMinutes();
    const minsDegrees = ((mins / 60) * 360) + ((seconds/60)*6) + 90;
    minsHand.style.transform = `rotate(${minsDegrees}deg)`;
    const hour = now.getHours();
    const hourDegrees = ((hour / 12) * 360) + ((mins/60)*30) + 90;
    hourHand.style.transform = `rotate(${hourDegrees}deg)`;
  }
  setInterval(setDate, 1000);
  setDate();