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CSS

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JavaScript

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HTML 

              
                <!-- The main container for the meter component -->
<div class="meter">
  <!-- Displays the current reading value -->
  <div class="reading">0</div>
  
  <!-- Container for the color wheel background -->
  <div class="colors-container">
    <div class="color-wheel">
    </div>
  </div>
  
  <!-- The knob and needle of the meter -->
  <div class="knob">
    <div class="needle">
      <div class="pointer"></div>
    </div>
  </div>
</div>

<!-- Commented out button for changing the reading manually -->
<!-- <button class="change-reading-btn">Change Reading</button> -->
!

CSS 

              
                /* Apply transition to all elements for smooth animations */
* {
  transition: all 0.2s;
}

/* Center the content in the middle of the viewport */
body {
  display: grid;
  place-content: center;
  height: 100vh;
  margin: 0px;
}

/* Style for the color wheel container */
.colors-container {
  height: 150px;
  overflow: hidden;
  width: 300px;
}

/* Create a colorful background using conic gradient */
.color-wheel {
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: conic-gradient(rgb(116,243,251), rgb(255,224,5) 90deg, rgb(5,147,255) 270deg, rgb(116,243,251));
}

/* Main container for the meter */
.meter {
  position: relative;
  width: 300px;
}

/* Style for the knob */
.knob {
  width: 100px;
  height: 100px;
  position: absolute;
  bottom: -50px;
  left: 100px;
  background: rgba(255,255,255,0.6);
  border-radius: 50%;
  box-shadow: 0px 5px 10px rgba(0,0,150,0.1),
    inset -5px 5px 10px rgba(255,255,255,1);
  backdrop-filter: blur(10px);
  display: grid;
  place-content: center;
  transform: rotate(-90deg);
}

/* Style for the needle */
.needle {
  background: #fff;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  position: relative;
  transform: rotate(30deg);
  filter: drop-shadow(0px 0px 10px rgba(0,0,150,0.2));
  transition: all 0.3s;
}

/* Style for the pointer (part of the needle) */
div.pointer {
  background: #fff;
  height: 100px;
  width: 10px;
  position: absolute;
  bottom: 25px;
  left: 20px;
  border-radius: 50% 50% 0px 0px;
}

/* Style for the reading display */
.reading {
  font-size: 50px;
  position: absolute;
  width: 100%;
  text-align: center;
  color: #fff;
  text-shadow: 0px 5px 10px rgba(0,0,0,0.3);
  font-family: arial;
  font-weight: bold;
  opacity: 0.2;
  top: 30px;
}
!

JS 

              
                // Select DOM elements
let changeReadingBtn = document.querySelector(".change-reading-btn");
let readingElement = document.querySelector(".reading");
let needle = document.querySelector(".needle");

// Uncomment this event listener to enable manual reading changes
// changeReadingBtn.addEventListener("click", () => {
//   changeReading();
// });

// Set an interval to change the reading every 200 milliseconds
setInterval(() => {
  changeReading();
}, 200);

// Function to change the reading and update the display
function changeReading() {
  // Generate a random reading between 0 and 180
  let newReading = parseInt(Math.random() * 181);
  console.log(newReading);
  
  // Update the reading display
  readingElement.innerText = newReading;
  
  // Rotate the needle to reflect the new reading
  needle.style.transform = `rotate(${newReading}deg)`;
}
!
999px

Console