QTreeview branch can't use transparent background

#include "MainWindow.h"

#include <QApplication>
#include <QFileSystemModel>
#include <QTreeView>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;

    // Create a file system model
    QFileSystemModel model;
    model.setRootPath("");

    // Create the QTreeView instance and set up the model
    QTreeView treeView(&w);
    treeView.setModel(&model);
    treeView.setRootIndex(model.index("")); // Set the root directory
    // Define the QSS style directly in code
    QString qss = "\
        QTreeView {\
            border: none;\
            border-top: 1px solid #14000000;\
            padding: 4px;\
            show-decoration-selected: 1;\
    }\
        QTreeView::item {\
            outline: none;\
            color: #101010;\
    }\
        QTreeView::item:hover, QTreeView::branch:hover {\
            background: #19203030;\
    }\
        QTreeView::item:selected, QTreeView::branch:selected {\
            background: #1900FFFF;\
            outline: none;\
    }";

        treeView.setStyleSheet(qss); // apply style
    w.setCentralWidget(&treeView);
    w.show();
    return a.exec();
}