A starting point for CSS code standards

manual/en-US/coding-standards/chapters/css.md

@@ -1,3 +1,220 @@
 ## CSS
+These guidelines have been assembled following an examination of emerging practices, ideas and existing styleguides, namely:
 
-@TODO - Add style guide
+1. [OOCSS Code Standards](https://github.com/stubbornella/oocss-code-standards)
+2. [Oneweb Style Guide](https://github.com/nternetinspired/OneWeb/blob/master/STYLEGUIDE.md)
+3. [Idiomatic CSS](https://github.com/necolas/idiomatic-css)
+
+
+## Commenting
+
+### Major sections
+Major code sections should be named in caps and within a full comment block, eg:
+```css
+/* ==========================================================================
+   PRIMARY NAVIGATION
+   ========================================================================== */
+```
+
+### Sub sections
+Subsections should be normally cased and within an open comment block.
+```css
+/* Mobile navigation
+   ========================================================================== */
+```
+
+### Verbose comments
+```css
+/**
+ * Short description using Doxygen-style comment format
+ *
+ * The first sentence of the long description starts here and continues on this
+ * line for a while finally concluding here at the end of this paragraph.
+ *
+ * The long description is ideal for more detailed explanations and
+ * documentation. It can include example HTML, URLs, or any other information
+ * that is deemed necessary or useful.
+ *
+ * @tag This is a tag named 'tag'
+ *
+ * TODO: This is a todo statement that describes an atomic task to be completed
+ *   at a later date. It wraps after 80 characters and following lines are
+ *   indented by 2 spaces.
+ */
+ ```
+
+### Basic comments
+```css
+/* Basic comment */
+```
+
+### Uncompiled LESS/Scss comments
+```css
+// These are stripped on compile.
+```
+
+## Class naming
+Use dashes to create compound class names:
+
+```css
+/* Good - use dashes */
+.compound-class-name {…}
+
+/* Bad - uses underscores */
+.compound_class_name {…}
+
+/* Bad - uses camelCase */
+.compoundClassName {…}
+
+/* Bad - does not use seperators */
+.compoundclassname {…}
+```
+
+### Indentation
+Rules should be indented one tab (equal to 4 spaces):
+
+```css
+/* Good */
+.example {
+	color: #000;
+	visibility: hidden;
+}
+
+/* Bad - all on one line */
+.example {color: #000; visibility: hidden;}
+```
+
+LESS/Scss should also be nested , with child selectors and rules indented again. Nested rules should also be spaced by one line:
+
+```css
+/* Good */
+.example {
+
+  > li {
+    float: none;
+
+	+ li {
+		margin-top: 2px;
+		margin-left: 0;
+	}
+
+  }
+
+}
+/* Bad - nested rules not indented */
+.example {
+
+	> li {
+	float: none;
+
+	+ li {
+	margin-top: 2px;
+	margin-left: 0;
+	}
+
+	}
+
+}
+/* Bad - nested rules not spaced */
+.example {
+  > li {
+    float: none;
+	+ li {
+		margin-top: 2px;
+		margin-left: 0;
+	}
+  }
+}
+```
+
+### Alignment
+The opening brace must be on the same line as the last selector and preceded by a space. The closing brace must be on its own line after the last property and be indented to the same level as the opening brace.
+
+```css
+/* Good */
+.example {
+    color: #fff;
+}
+
+/* Bad - closing brace is in the wrong place */
+.example {
+    color: #fff;
+    }
+
+/* Bad - opening brace missing space */
+.example{
+    color: #fff;
+}
+```
+
+### Property Format
+Each property must be on its own line and indented one level. There should be no space before the colon and one space after. All properties must end with a semicolon.
+
+```css
+/* Good */
+.example {
+    background: black;
+    color: #fff;
+}
+
+/* Bad - missing spaces after colons */
+.example {
+    background:black;
+    color:#fff;
+}
+
+/* Bad - missing last semicolon */
+.example {
+    background: black;
+    color: #fff
+}
+```
+
+### HEX values
+HEX values must be declared in lowercase and shorthand:
+```css
+/* Good */
+.example {
+    color: #eee;
+}
+
+/* Bad */
+.example {
+    color: #EEEEEE;
+}
+```
+
+### Attribute selectors
+Always use double quotes around attribute selectors.
+
+```css
+/* Good */
+input[type="button"] {
+    ...
+}
+
+/* Bad - missing quotes */
+input[type=button] {
+    ...
+}
+
+/* Bad - using single quote */
+input[type='button'] {
+    ...
+}
+```
+
+### Zero value units
+Zero values should not carry units.
+
+```css
+/* Good */
+.example {
+   padding: 0;
+}
+
+/* Bad - uses units */
+.example {
+   padding: 0px;
+}
+```