drag and drop clone element javascript

<div class="container">
        <h1>Drag & Drop Clone Elements</h1>
        <p class="subtitle">Drag items from the palette to the canvas (clones automatically)</p>
        
        <div class="workspace">
            <div class="panel">
                <h2>Element Palette</h2>
                <div class="source-items">
                    <div class="draggable-item" draggable="true" data-type="box">
                        📦 Box
                    </div>
                    <div class="draggable-item" draggable="true" data-type="circle">
                        ⭕ Circle
                    </div>
                    <div class="draggable-item" draggable="true" data-type="star">
                        ⭐ Star
                    </div>
                    <div class="draggable-item" draggable="true" data-type="heart">
                        ❤️ Heart
                    </div>
                    <div class="draggable-item" draggable="true" data-type="diamond">
                        💎 Diamond
                    </div>
                    <div class="draggable-item" draggable="true" data-type="rocket">
                        🚀 Rocket
                    </div>
                </div>
            </div>

            <div class="panel">
                <h2>Canvas</h2>
                <div class="drop-zone" id="dropZone"></div>
            </div>
        </div>

        <div class="controls">
            <button class="btn" onclick="clearCanvas()">Clear Canvas</button>
        </div>
    </div>  

  * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #4B3621 0%, #2a1f13 100%);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            padding: 40px 20px;
        }

        .container {
            max-width: 1200px;
            width: 100%;
        }

        h1 {
            color: #fff;
            text-align: center;
            margin-bottom: 10px;
            font-size: 2em;
            font-weight: 300;
            letter-spacing: 1px;
        }

        .subtitle {
            color: rgba(255, 255, 255, 0.7);
            text-align: center;
            margin-bottom: 40px;
            font-size: 0.95em;
        }

        .workspace {
            display: grid;
            grid-template-columns: 1fr 2fr;
            gap: 30px;
            margin-bottom: 20px;
        }

        .panel {
            background: rgba(255, 255, 255, 0.95);
            border-radius: 12px;
            padding: 30px;
            box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
        }

        .panel h2 {
            color: #4B3621;
            margin-bottom: 20px;
            font-size: 1.3em;
            font-weight: 500;
            border-bottom: 2px solid #4B3621;
            padding-bottom: 10px;
        }

        .source-items {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
            gap: 15px;
        }

        .draggable-item {
            background: linear-gradient(135deg, #4B3621 0%, #6b4e2f 100%);
            color: white;
            padding: 20px;
            border-radius: 8px;
            cursor: move;
            text-align: center;
            transition: all 0.3s ease;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
            user-select: none;
        }

        .draggable-item:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(75, 54, 33, 0.4);
        }

        .draggable-item.dragging {
            opacity: 0.5;
            transform: scale(0.95);
        }

        .drop-zone {
            min-height: 300px;
            border: 2px dashed #4B3621;
            border-radius: 8px;
            padding: 20px;
            display: flex;
            flex-wrap: wrap;
            gap: 15px;
            align-content: flex-start;
            transition: all 0.3s ease;
        }

        .drop-zone.drag-over {
            background: rgba(75, 54, 33, 0.1);
            border-color: #6b4e2f;
            border-style: solid;
        }

        .drop-zone.empty::before {
            content: 'Drop items here';
            position: absolute;
            color: #999;
            font-size: 1.1em;
            pointer-events: none;
        }

        .dropped-item {
            position: relative;
            background: linear-gradient(135deg, #6b4e2f 0%, #8a6338 100%);
        }

        .remove-btn {
            position: absolute;
            top: -8px;
            right: -8px;
            background: #e74c3c;
            color: white;
            border: none;
            border-radius: 50%;
            width: 24px;
            height: 24px;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 14px;
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .dropped-item:hover .remove-btn {
            opacity: 1;
        }

        .remove-btn:hover {
            background: #c0392b;
        }

        .controls {
            text-align: center;
            margin-top: 20px;
        }

        .btn {
            background: linear-gradient(135deg, #4B3621 0%, #6b4e2f 100%);
            color: white;
            border: none;
            padding: 12px 30px;
            border-radius: 6px;
            cursor: pointer;
            font-size: 1em;
            transition: all 0.3s ease;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
        }

        .btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(75, 54, 33, 0.4);
        }

        @media (max-width: 768px) {
            .workspace {
                grid-template-columns: 1fr;
            }
        }

  const draggables = document.querySelectorAll('.draggable-item');
        const dropZone = document.getElementById('dropZone');
        let draggedElement = null;

        draggables.forEach(item => {
            item.addEventListener('dragstart', handleDragStart);
            item.addEventListener('dragend', handleDragEnd);
        });

        dropZone.addEventListener('dragover', handleDragOver);
        dropZone.addEventListener('drop', handleDrop);
        dropZone.addEventListener('dragleave', handleDragLeave);

        function handleDragStart(e) {
            draggedElement = this;
            this.classList.add('dragging');
            e.dataTransfer.effectAllowed = 'copy';
            e.dataTransfer.setData('text/html', this.innerHTML);
        }

        function handleDragEnd(e) {
            this.classList.remove('dragging');
        }

        function handleDragOver(e) {
            e.preventDefault();
            e.dataTransfer.dropEffect = 'copy';
            dropZone.classList.add('drag-over');
            return false;
        }

        function handleDragLeave(e) {
            if (e.target === dropZone) {
                dropZone.classList.remove('drag-over');
            }
        }

        function handleDrop(e) {
            e.preventDefault();
            e.stopPropagation();
            dropZone.classList.remove('drag-over');

            if (draggedElement) {
                const clone = draggedElement.cloneNode(true);
                clone.classList.remove('dragging');
                clone.classList.add('dropped-item');
                clone.draggable = false;
                
                const removeBtn = document.createElement('button');
                removeBtn.className = 'remove-btn';
                removeBtn.innerHTML = '×';
                removeBtn.onclick = function() {
                    clone.remove();
                    updateEmptyState();
                };
                
                clone.appendChild(removeBtn);
                dropZone.appendChild(clone);
                updateEmptyState();
            }

            draggedElement = null;
            return false;
        }

        function updateEmptyState() {
            if (dropZone.children.length === 0) {
                dropZone.classList.add('empty');
            } else {
                dropZone.classList.remove('empty');
            }
        }

        function clearCanvas() {
            dropZone.innerHTML = '';
            updateEmptyState();
        }

        updateEmptyState();