In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.

Code words in text, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "The sizes attribute can also be used with the <picture> element, but we're going to focus on using the sizes attribute with the <img> tag."

A block of code is set as follows:

*, *:before, *:after {
    box-sizing: border-box;
}

//Moble-first Media Queries Mixin
@mixin forLargeScreens($width) {
    @media (min-width: $width/16+em) { @content }
}

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

*, *:before, *:after {
    box-sizing: border-box;
}

//Moble-first Media Queries Mixin
@mixin forLargeScreens($width) {
    @media (min-width: $width/16+em) { @content }
}

Any command-line input or output is written as follows:

gem install sass

New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: "clicking the Next button moves you to the next screen".