body {
    background: #f9f9f9;
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}
.container {
    max-width: 600px;
    margin: 40px auto;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 2px 16px rgba(0,0,0,0.08);
    padding: 32px;
    text-align: center;
}
.pdf-container {
    width: 100%;
    height: 500px;
    margin-bottom: 24px;
}
iframe#pdfFrame {
    width: 100%;
    height: 100%;
    border: 1px solid #ddd;
    border-radius: 8px;
    background: #fff;
}
.btn {
    display: inline-block;
    margin: 16px 0;
    padding: 10px 28px;
    background: #007bff;
    color: #fff;
    border-radius: 6px;
    text-decoration: none;
    font-size: 1.1em;
    transition: background .2s;
    cursor: pointer;
}
.btn:hover {
    background: #0056b3;
}
.qr-section {
    margin-top: 32px;
}
.qr-btn {
    margin-left: 0;
}
#pdfFrame {
    border: 1px solid #ddd;
    border-radius: 8px;
    background: #fff;
    min-height: 400px;
}