body {
            font-family: Arial, sans-serif;
            margin: 0;
            padding: 0;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            height: 100vh;
            background-color: #f4f4f9;
        }

        h1 {
            color: #333;
        }

        #dropzone {
            width: 80%;
            max-width: 600px;
            height: 200px;
            border: 2px dashed #ccc;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-direction: column;
            background-color: #fff;
            color: #888;
            margin-bottom: 20px;
        }

        #dropzone.dragover {
            border-color: #007bff;
            color: #007bff;
        }

        #uploadInput {
            display: none;
        }

        #pdfPages {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            width: 80%;
            max-width: 600px;
            margin: 20px auto;
        }

        .page {
            width: 100px;
            height: 140px;
            border: 1px solid #ccc;
            border-radius: 4px;
            display: flex;
            align-items: center;
            justify-content: center;
            background-color: #fff;
            cursor: grab;
            overflow: hidden;
        }

        .page.dragging {
            opacity: 0.5;
        }

        img {
            max-width: 100%;
            max-height: 100%;
        }

        #downloadBtn, #uploadBtn {
            padding: 10px 20px;
            margin: 10px 0;
            background-color: #007bff;
            color: white;
            border: none;
            border-radius: 4px;
            cursor: pointer;
            font-size: 16px;
        }

        #downloadBtn:disabled {
            background-color: #ccc;
            cursor: not-allowed;
        }
        #deleteZone {
            width: 80%;
            max-width: 600px;
            height: 100px;
            border: 2px dashed red;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            background-color: #ffe6e6;
            color: red;
            font-size: 16px;
            margin-top: 20px;
            transition: background-color 0.3s, color 0.3s;
        }
        
        #deleteZone.dragover {
            background-color: red;
            color: white;
        }