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@@ -4,7 +4,8 @@ This project produces the cheatsheet at [cljs.info/cheatsheet]
 
 ## Design
 
-TODO: write this section
+You can read about some of the design decisions that went into the cheatsheet
+[here](design.md).
 
 ## Development Setup
 
diff --git a/design.md b/design.md
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+# ClojureScript Cheatsheet Design
+
+Below are some design notes for the [ClojureScript cheatsheet].
+
+## Type
+
+Open Sans (weights 300, 400, 600) was chosen for its clean appearance and
+excellent legibility. Droid Sans Mono was chosen as a compliment pair for
+monospaced code. Both typefaces have a neutral appearance and keep the focus on
+the content, not the type.
+
+Type differentiation is used to distinguish between groups headers, section
+headers, row labels, and table symbols. Each has a distinct appearance and can
+be recognized at a glance.
+
+## Info Tooltips
+
+Info tooltips (marked with the circle "i" icon) provide context and additional
+information helpful to developers coming from other languages. Comparisons to
+JavaScript are mentioned as relevant. Tooltips are unobtrusive unless hovered
+over. Grey is used to make them visually "wash over" when not needed.
+
+Tooltips have a small mouse pointer launch target, but once opened the range
+expands to allow for the mouse to enter the tooltip body and "explore" the
+content. This also allows the user to copy/paste content from a tooltip.
+
+## Tables
+
+Tables contain no additional marks other than labels and content. Color is used
+to separate table rows.
+
+## Colors
+
+High contrast colors are used to ensure legibility on a wide range of devices
+and screens.
+
+## Literal Forms
+
+Where appropriate, section headers contain the literal representation or
+shorthand version of their form. Users already familiar with the literal forms
+will instantly recognize their connection to the section. Users unfamiliar with
+the literal forms may be confused at first, but should eventually have an
+"aha!" moment when they make the connection. This is my favorite feature of the
+cheatsheet :)
+
+## Search
+
+Search highlights matching symbols in yellow and leaves the containing section
+visible for context. Sections with no match are hidden and the content "folds"
+smartly around the matched sections. Red is used in the search bar to indicate
+no match.
+
+## Inline Tooltips
+
+Inline tooltips provide rich information about each function, macro, or special
+form. Like the info tooltips, inline tooltips allow for the mouse to enter the
+body to "explore" the content and copy/paste.
+
+Mousing over a related symbol in a tooltip highlights it on the page, visually
+connecting related sections. When a related symbol is underneath the tooltip
+body (as often happens due to the organization of the symbols), opacity is used
+to show the location of the related symbol.
+
+## Content Organization
+
+Sections are defined and ordered by common usage first, implementation
+organization second. Links are repeated in multiple sections where appropriate.
+
+## Footer
+
+The footer contains no color and provides relevant links to related material.
+
+## Documentation
+
+Documentation is contained in simple [kidif files] that allow for management
+and collaboration using existing tools (git, text editors, etc).
+
+Docstrings were extracted from the code and converted to Markdown format to
+allow for more structure than simple text can provide (ie: code highlighting,
+links, tables, etc). The descriptions were edited to have consistent voice and
+structure.
+
+## Responsive Layout
+
+The content folds into three layouts depending on browser width. The sections
+are organized in each layout to fill the space as best they can.
+
+[ClojureScript cheatsheet]:http://cljs.info/cheatsheet
+[kidif files]:https://github.com/oakmac/kidif.js