How can I compile multiple less files into one css file?

[zhaoyi0113]

I am using below scripts to compile less files:

"build-css": "node-less-chokidar src/scenes -o src/scenes",
"watch-css": "yarn run build-css && node-less-chokidar src/scenes -o src/scenes --watch --recursive",

I will compile each less file to one css file. I wonder whether there is a way for me to compile all less files into one big css file.