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                <html lang="en">
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Decimal-Binary Converter</title>
    <!-- Google Fonts -->
    <!-- Stylesheet -->
    <link rel="stylesheet" href="style.css" />
    <div class="container">
      <h2>Decimal Binary Converter</h2>
      <div class="wrapper">
        <div class="input-wrapper">
          <label for="dec-inp">Decimal:</label>
          <input type="number" id="dec-inp" />
        <div class="input-wrapper">
          <label for="bin-inp">Binary:</label>
          <input type="number" id="bin-inp" />
      <p id="error-msg"></p>
    <!-- Script -->
    <script src="script.js"></script>


                * {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
body {
  background-color: #0075ff;
.container {
  background-color: #ffffff;
  width: 80vmin;
  max-width: 37.5em;
  padding: 3em 2.5em;
  position: absolute;
  transform: translate(-50%, -50%);
  top: 50%;
  left: 50%;
  border-radius: 0.62em;
  box-shadow: 0 1.2em 2.5em rgba(0, 21, 44, 0.18);
h2 {
  font-size: 1.8em;
  color: #0075ff;
  text-align: center;
  font-weight: 600;
  letter-spacing: 0.5px;
  margin-bottom: 1.3em;
.wrapper {
  display: flex;
  justify-content: space-between;
  gap: 1.8em;
label {
  display: block;
  margin-bottom: 0.5em;
  font-weight: 500;
  color: #050121;
input {
  position: relative;
  font-size: 1.1em;
  width: 100%;
  padding: 0.5em;
  border-radius: 0.2em;
  border: 1.5px solid #43405c;
  color: #43405c;
  outline: none;
input:focus {
  border-color: #0075ff;
#error-msg {
  text-align: center;
  margin-top: 1.25em;
  color: #ff4362;


                //Initial References
let decInp = document.getElementById("dec-inp");
let binInp = document.getElementById("bin-inp");
let errorMsg = document.getElementById("error-msg");

//Convert decimal to binary when user inputs in the decimal field
decInp.addEventListener("input", () => {
  let decValue = parseInt(decInp.value);
  //Converts the decimal value to binary
  binInp.value = decValue.toString(2);

//Convert binary to decimal when user inputs in the binary field
binInp.addEventListener("input", () => {
  let binValue = binInp.value;
  //If the binary number is valid convert it to decimal
  if (binValidator(binValue)) {
    decInp.value = parseInt(binValue, 2);
    errorMsg.textContent = "";
  //Else display an error message
  else {
    errorMsg.textContent = "Please Enter An Valid Binary Input";

  //Function to check if the binary number is valid i.e it does not contain any number other than 0 and 1
  function binValidator(num) {
    for (let i = 0; i < num.length; i++) {
      if (num[i] != "0" && num[i] != "1") {
        return false;
    return true;