"Purple should never be used outside of officially endorsed Heroku products or without explicit permission."

I wonder how others feel about this, I really enjoy breaking apart existing websites and having a guide like this is certainly something I can use for inspiration in any of my projects - but I also wonder about the above clause and any implications it may have on copycat behaviour.

I doubt if they care about copycats. At first glance I thought - "WTF? Why they publish this and do not make it Open Source". But after a while I think it's good for few reasons: - it can be inspiring for others - in terms of usability, typography, etc - it illustrates how to make good spec for your company / employees and avoid this "i-just-saw-nice-plugin-lets-use-it" behaviour - at some point this illustrates company`s culture - this shows how "organized" and "enterprisy" they are - I do belive, that there are still some people who judge herokus website and think, that this must be some kind of smaller hosting company for ones pet projects

I think mainly they don't want you making a tool that works with Heroku and using their branding so it's confusing for users as to whether it's endorsed or not.

Alex Lande did something similar for WalMart http://walmartlabs.github.io/web-style-guide/ ... on the tail of that, he built Radium. We had many conversations in between about the shortcomings of CSS after working on such large projects. http://projects.formidablelabs.com/radium/

GitHub has a similar "living" style guide that is open source: http://primercss.io/

Firebase has a similar style guide:

https://www.firebase.com/docs/styleguide.html

> Purple should never be used outside of officially endorsed Heroku products or without explicit permission.

then why opensource it at first place? Bootstrap became popular even though it used some Twitter design styles. How is it a bad thing?

When you write this in the lib description,you're making sure nobody's going to use that.

It isn't open source to begin with.

> The Purple source code and implementation details are limited to internal Heroku employees.

So was this really intended to be shared? Did someone "leak" it per se? or did they just want to show it off as best practice?

The red box has some text that says:

> It is publicly documented in order to illustrate our design philosophy and process.

How do people feel about the BEM naming scheme for CSS rules? It looks like overkill when used with a preprocessor but I haven't actually taken time to try it yet. I also find myself absolutely turned off by the idea of a class that mixes underscores and dashes.

Even though it's not open source, it's still great for inspiration.

This is just a Bootstrap theme. Even the column classes are the same.

Yeah, agreed, almost all of it is verbatim bootstrap code with a few extra classes added in for padding and some other light things.