.pdfbu-filters {
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 20px;
}
.pdfbu-year-select {
    font-size: 18px;
    padding: 8px 12px;
    border-radius: 4px;
}
.pdfbu-month-list {
    display: flex;
    list-style: none;
    padding: 0;
    margin: 0;
    gap: 10px;
}
.pdfbu-month-item {
    font-size: 18px;
    padding: 8px 16px;
    border: 1px solid #ccc;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.3s;
}
.pdfbu-month-item.active,
.pdfbu-month-item:hover {
    background: #0073aa;
    color: #fff;
    border-color: #0073aa;
}