SaaS Boilerplate is a complete, working app shell you can open by double-clicking a file: a polished marketing page, sign in and sign up, a dashboard with sidebar navigation, projects, a team page with invites and roles, a billing page with a mock plan switcher, tabbed settings, a notifications drawer and a Ctrl/Cmd+K command palette.

It is plain HTML, CSS and vanilla JavaScript with no build step and no dependencies. It is framework-free on purpose, but it is organised the way a React/Next.js app is: one small render function per view, layouts, a tiny router and store, and every network call isolated in a single js/api.js file with TODO comments. That makes it fast to customize today and straightforward to port to React or Next.js later.

It is not a React project itself, and it has no real backend - auth, billing and email are mocks backed by localStorage.

Design is dark-first with a lime accent and a warm light theme, serif display headings, system fonts only, responsive from 360px to 1920px, keyboard accessible, and respectful of reduced-motion. Everything is original and released under CC0.