.gitignore file for front-end projects

.gitignore

# Created by https://www.gitignore.io/api/node,bower,osx,linux,windows,dropbox,sass,less,grunt,sublimetext,code

### Node ###
# Logs
logs
*.log
npm-debug.log*

# Runtime data
pids
*.pid
*.seed

# Directory for instrumented libs generated by jscoverage/JSCover
lib-cov

# Coverage directory used by tools like istanbul
coverage

# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
.grunt

# node-waf configuration
.lock-wscript

# Compiled binary addons (http://nodejs.org/api/addons.html)
build/Release

# Dependency directory
# https://docs.npmjs.com/misc/faq#should-i-check-my-node-modules-folder-into-git
node_modules

# Optional npm cache directory
.npm

# Optional REPL history
.node_repl_history


### Bower ###
bower_components
.bower-cache
.bower-registry
.bower-tmp


### OSX ###
.DS_Store
.AppleDouble
.LSOverride

# Icon must end with two \r
Icon


# Thumbnails
._*

# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns

# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk


### Linux ###
*~

# KDE directory preferences
.directory

# Linux trash folder which might appear on any partition or disk
.Trash-*


### Windows ###
# Windows image file caches
Thumbs.db
ehthumbs.db

# Folder config file
Desktop.ini

# Recycle Bin used on file shares
$RECYCLE.BIN/

# Windows Installer files
*.cab
*.msi
*.msm
*.msp

# Windows shortcuts
*.lnk


### Dropbox ###
# Dropbox settings and caches
.dropbox
.dropbox.attr
.dropbox.cache


### Sass ###
.sass-cache/
*.css.map


### Less ###
*.css


### grunt ###
# Grunt usually compiles files inside this directory
dist/

# Grunt usually preprocesses files such as coffeescript, compass... inside the .tmp directory
.tmp/


### SublimeText ###
# cache files for sublime text
*.tmlanguage.cache
*.tmPreferences.cache
*.stTheme.cache

# workspace files are user-specific
*.sublime-workspace

# project files should be checked into the repository, unless a significant
# proportion of contributors will probably not be using SublimeText
# *.sublime-project

# sftp configuration file
sftp-config.json


### Code ###
# Visual Studio Code - https://code.visualstudio.com/
.settings/
.vscode/

Searching .gitignore template for frontend development and end up here, thank you for your elaborated share. But I seem to find a little bug here, should the matching rule for LESS stylesheets be *.less instead of *.css?

.less are actually your source files, whereas .css are just some intermediate results that .less files get transpiled into during the build. So you normally want to store your source files in git and ignore build artifacts.