CSS style guide

Formatting

• Use soft tabs (2 spaces) for indentation
• Prefer dashes over camelCasing in class names
• Do not use ID selectors
• When using multiple selectors in a rule declaration, give each selector its own line
• Put a space before the opening brace { in rule declarations
• In properties, put a space after, but not before, the : character
• Put closing braces } of rule declarations on a new line
• Put blank lines between rule declarations

Comment

• Prefer line comments (// in Sass-land) to block comments.
• Prefer comments on their own line. Avoid end-of-line comments.
• Write detailed comments for code that isn’t self-documenting:
  
  • Uses of z-index
  • Compatibility or browser-specific hacks

Order

1. Positioning properties
2. Display properties
3. Box properties
4. Content properties (including background)
5. Pseudo properties