Where is bootstrap-responsive.css?

I know that by default the bootstrap doesn't come with the file, but after I customized (I've selected all the responsive features!) I still can't see the file. At the docs, it says that I should do this on head tag:

<meta name="viewport" content="width=device-width, initial-scale=1.0"> <link href="assets/css/bootstrap-responsive.css" rel="stylesheet">

But the truth is that I don't even have the folder assets. What I do have is:

\bootstrap     \img     \css     \js

Can anyone help me?

Is Bootstrap CSS responsive?

Bootstrap includes a responsive, mobile first fluid grid system that appropriately scales up to 12 columns as the device or viewport size increases. It includes predefined classes for easy layout options, as well as powerful mixins for generating more semantic layouts.

Is Bootstrap responsive by default?

Apart from this, you're good to go: Bootstrap is responsive by default.

Since Bootstrap 3 you don't need responsive.css anymore. Because it is inside default bootstrap.css.

Related: https://stackoverflow.com/a/16379181/429938