Sample gulp file for sass to css into wwwroot/css

gulpfile.js

var gulp = require("gulp"),
scss = require("gulp-sass");

gulp.task("sass", function () {
return gulp.src('Styles/*.scss')
  .pipe(scss.sync().on('error', scss.logError))
  .pipe(gulp.dest('wwwroot/css'));
});

gulp.task('watch', function () {
  gulp.watch('Styles/*.scss', ['sass']);
});

// In VS Code you have to run task which related with your tasks.json file.

tasks.json

{
    "version": "0.1.0",
    "command": "gulp",
    "isShellCommand": true,
    "args": [
        "--no-color"
    ],
    "task": [
        {
            "taskName": "sass",
            "isBuildCommand": true,
            "showOutput": "always"
        }
        {
            "taskName": "watch",
            "isBuildCommand": true,
            "showOutput": "always"
        }
    ]
}