How to clear the contents of a file in gulp? And how to make sure that a new folder does not appear when compiling SASS?

Question

gulp.js

Hello everyone, I've run into a few problems. I collect a new assembly in GULP and this is the point:
1) I use concat-css to connect all CSS files in style.css, but I noticed that concat-css connects everything without deleting what was, and gulp-clean deletes the file , after which concat-css gives an error like there is no such file, where to connect your CSS? Is it possible somehow to clear only the content of style.css so that later I can just put the necessary code there?
2) I compile SCSS to CSS, but it creates an unnecessary folder in the css folder, i.e. I specified asssets/app/css and I get assets/app/css/sass/ the desired file . How to remove this subfolder and compile the code exactly to CSS
Screenshots of the necessary tasks, thanks in advance.

Answer 1

вот тебе ответ-)