style.css

body {
    background-color: #f8f9fa;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.card {
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    border: none;
    transition: transform 0.2s;
}

.card:hover {
    transform: translateY(-5px);
}

.card-header {
    font-weight: 600;
}
#invoiceFieldsList,
#newFieldsList {
    max-height: 300px;
    overflow-y: auto;
}

.list-group-item {
    padding: 0.75rem 1.25rem;
}

.remove-field {
    padding: 0 0.5rem;
    line-height: 1;
}
#pdfPreview {
    background: #f8f9fa;
    border-radius: 0.25rem;
    padding: 1rem;
    overflow: auto;
}

#pdfViewer {
    display: flex;
    justify-content: center;
    align-items: center;
    background-color: #fff;
    border: 1px solid #dee2e6;
    border-radius: 0.25rem;
    margin: 0 auto;
}

#pdfViewer canvas {
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
#localPath {
    margin-top: 0.5rem;
}

#newFieldsSection {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid #eee;
}
.btn {
    font-weight: 500;
    padding: 0.5rem 1.5rem;
}

.display-4 {
    font-weight: 700;
    color: #2c3e50;
}

.lead {
    color: #7f8c8d;
}