3D Press Button Calculator

This 3D Press Button Calculator is an interactive web-based calculator designed with HTML, CSS, and JavaScript. It features realistic 3D button presses, smooth gradient backgrounds, and a clean grid layout — perfect for learning UI design, button animations, and responsive web development.

How to use: Copy and paste the HTML, CSS, and JavaScript into your project.
Customize colors: Adjust gradients or background colors in CSS to match your theme.
Change button style: Modify box-shadow and transform to enhance 3D effect.
Edit layout: Change the CSS grid settings to rearrange buttons.
Add functions: Extend JavaScript logic for more operations.
Responsive design: Use media queries for mobile and tablet support.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Bright Calculator</title>
  <style>
    @import url('https://fonts.googleapis.com/css2?family=Roboto:wght@500&display=swap');
    body {
      display: flex;
      justify-content: center;
      align-items: center;
      height: 100vh;
      margin: 0;
      background: linear-gradient(135deg, #f6d365, #fda085);
      font-family: 'Roboto', sans-serif;
    }
    .calculator {
      background: #fff;
      border-radius: 20px;
      padding: 25px;
      box-shadow: 0 15px 30px rgba(0,0,0,0.2);
      width: 300px;
    }
    #result {
      width: 93%;
      height: 60px;
      font-size: 28px;
      text-align: right;
      padding: 10px;
      margin-bottom: 20px;
      border-radius: 15px;
      border: none;
      background: #f0f0f0;
      color: #333;
    }
    .buttons {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 15px;
    }
    button {
      padding: 18px;
      font-size: 20px;
      border: none;
      border-radius: 15px;
      cursor: pointer;
      transition: all 0.2s;
      font-weight: bold;
      box-shadow: 0 5px #ccc;
    }
    button:hover {
      transform: translateY(-3px);
      box-shadow: 0 8px #bbb;
    }
    
    .number { background: linear-gradient(145deg, #ffecd2, #fcb69f); color: #333; }
    .operator { background: linear-gradient(145deg, #ff7e5f, #feb47b); color: #fff; }
    .equal { background: linear-gradient(145deg, #43cea2, #185a9d); color: #fff; grid-row: span 2; }
    .clear { background: linear-gradient(145deg, #ff6a88, #ff99ac); color: #fff; }
    .zero { grid-column: span 2; background: linear-gradient(145deg, #ffd194, #d1913c); color: #333; }
  </style>
</head>
<body>
  <div class="calculator">
    <input type="text" id="result" readonly placeholder="0">
    <div class="buttons">
      <button class="clear" onclick="clearResult()">C</button>
      <button class="operator" onclick="appendValue('/')">/</button>
      <button class="operator" onclick="appendValue('*')">*</button>
      <button class="operator" onclick="appendValue('-')">-</button>
      <button class="number" onclick="appendValue('7')">7</button>
      <button class="number" onclick="appendValue('8')">8</button>
      <button class="number" onclick="appendValue('9')">9</button>
      <button class="operator" onclick="appendValue('+')">+</button>
      <button class="number" onclick="appendValue('4')">4</button>
      <button class="number" onclick="appendValue('5')">5</button>
      <button class="number" onclick="appendValue('6')">6</button>
      <button class="equal" onclick="calculateResult()">=</button>
      <button class="number" onclick="appendValue('1')">1</button>
      <button class="number" onclick="appendValue('2')">2</button>
      <button class="number" onclick="appendValue('3')">3</button>
      <button class="zero" onclick="appendValue('0')">0</button>
      <button class="number" onclick="appendValue('.')">.</button>
    </div>
  </div>
  <script>
  let expression = '';
    function appendValue(v){ expression += v; document.getElementById('result').value = expression; }
    function clearResult(){ expression = ''; document.getElementById('result').value = ''; }
    function calculateResult(){
      try{ expression = eval(expression).toString(); document.getElementById('result').value = expression; }
      catch{ document.getElementById('result').value = 'Error'; expression = ''; }
    }
  </script>
</body>
</html>