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                <html lang="en">
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Simple Interest Calculator</title>
    <!-- Google Fonts -->
    <!-- Stylesheet -->
    <link rel="stylesheet" href="style.css" />
    <div class="container">
      <div class="input-wrapper">
        <div class="wrapper">
          <label for="principal">Principal($):</label>
          <input type="number" id="principal" value="1000" />
        <div class="wrapper">
          <label for="rate">Rate:</label>
          <input type="number" id="rate" value="5" />
      <label for="time">Time:</label>
      <div class="time-wrapper">
        <input type="number" id="time" value="1" />
        <select name="duration" id="duration">
          <option value="year">Year</option>
          <option value="month">Month</option>
      <button id="calculate-btn">Calculate</button>
      <div id="result"></div>
    <!-- Script -->
    <script src="script.js"></script>


                * {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
body {
  height: 100vh;
  background: linear-gradient(#01e26e, #72ffb4);
.container {
  background-color: #ffffff;
  position: absolute;
  transform: translate(-50%, -50%);
  top: 50%;
  left: 50%;
  width: 80vw;
  max-width: 600px;
  min-width: 350px;
  padding: 60px 30px;
  border-radius: 10px;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
label {
  display: block;
  font-size: 22px;
  margin-bottom: 10px;
  font-weight: 500;
input {
  margin-bottom: 20px;
  border: none;
  font-size: 20px;
  border-bottom: 2px solid #585858;
  color: #585858;
  padding: 2px 15px;
input:focus {
  outline: none;
  border-bottom: 2.4px solid #01e26e;
.input-wrapper {
  display: flex;
  justify-content: space-between;
  gap: 20px;
.input-wrapper input {
  width: 100%;
.time-wrapper input {
  width: 60%;
select {
  width: 35%;
  border: 1px solid #585858;
  font-size: 20px;
  margin-left: 3%;
  padding: 8px 0;
  border-radius: 5px;
button {
  display: block;
  background-color: #01e26e;
  border: none;
  color: #ffffff;
  margin: 20px auto 0 auto;
  padding: 15px 40px;
  font-size: 20px;
  border-radius: 5px;
#result {
  background-color: #c6ffe2;
  margin-top: 30px;
  color: #585858;
  text-align: center;
  font-size: 18px;
  padding: 20px;
  border-radius: 5px;
#result div {
  margin-bottom: 10px;
#result span {
  color: #000000;
  font-weight: 500;


                let calculateBtn = document.getElementById("calculate-btn");
let result = document.getElementById("result");
let calculate = () => {
  let p = Number(document.getElementById("principal").value);
  let r = Number(document.getElementById("rate").value);
  let t = Number(document.getElementById("time").value);
  let duration = document.getElementById("duration").value;
  let simpleInterest =
    duration == "year" ? (p * r * t) / 100 : (p * r * t) / 1200;
  let amount = p + simpleInterest;

  result.innerHTML = `<div>Principal Amount: <span>${p.toFixed(2)}</span></div>
  <div>Total Interest: <span>${simpleInterest.toFixed(2)}</span></div>
  <div>Total Amount: <span>${amount.toFixed(2)}</span></div>`;
calculateBtn.addEventListener("click", calculate);
window.addEventListener("load", calculate);