index.html

<!DOCTYPE html>
<html>
<head>
    <title>Basic Calculator</title>
    <link rel="stylesheet" type="text/css" href="styles.css">
</head>
<body>
    <div class="calculator">
        <div class="display">
            <input type="text" id="result" readonly>
        </div>
        <div class="buttons">
            <button class="operator" onclick="clearResult()">C</button>
            <button class="operator" onclick="removeLastChar()">CE</button>
            <button onclick="appendToResult('7')">7</button>
            <button onclick="appendToResult('8')">8</button>
            <button onclick="appendToResult('9')">9</button>
            <button class="operator" onclick="performOperation('/')">/</button>
            <button onclick="appendToResult('4')">4</button>
            <button onclick="appendToResult('5')">5</button>
            <button onclick="appendToResult('6')">6</button>
            <button class="operator" onclick="performOperation('*')">*</button>
            <button onclick="appendToResult('1')">1</button>
            <button onclick="appendToResult('2')">2</button>
            <button onclick="appendToResult('3')">3</button>
            <button class="operator" onclick="performOperation('-')">-</button>
            <button onclick="appendToResult('0')">0</button>
            <button onclick="appendToResult('.')">.</button>
            <button class="operator" onclick="calculateResult()">=</button>
            <button class="operator" onclick="performOperation('+')">+</button>
        </div>
    </div>
    <script src="script.js"></script>
</body>
</html>