css/docs/content/principles/scss.md

title	path
SCSS	principles/scss

Spacing

• Use soft-tabs with a two space indent. Spaces are the only way to guarantee code renders the same in any person's environment.
• Put spaces after : in property declarations.
• Put spaces before { in rule declarations.
• Put line breaks between rulesets.
• When grouping selectors, keep individual selectors to a single line.
• Place closing braces of declaration blocks on a new line.
• Each declaration should appear on its own line for more accurate error reporting.

Formatting

• Use hex color codes #000 unless using rgba() in raw CSS (the SCSS rgba() function is overloaded to accept hex colors, as in rgba(#000, .5)).
• Use // for comment blocks (instead of /* */).
• Avoid specifying units for zero values, e.g., margin: 0; instead of margin: 0px;.
• Strive to limit use of shorthand declarations to instances where you must explicitly set all the available values.

Guidelines for using Sass features (WIP)

When and when not to create:

• Variables
• Mixins
• Functions

Lint rules (WIP)

As a rule of thumb, avoid unnecessary nesting in SCSS. At most, aim for three levels. If you cannot help it, step back and rethink your overall strategy (either the specificity needed, or the layout of the nesting).

• Nesting depth: 3
• Extends: no
• Duplicated properties: no
• Final new lines: yes
• Hex length: 6
• ID selectors: no
• Leading zero: yes
• Naming format: lowercase-with-hyphens
• Property order: see HTML property order
• Selector depth: 3
• Single line properties: yes

Examples

Here are some good examples that apply the above guidelines:

// Example of good basic formatting practices
.styleguide-format {
  color: #000;
  background-color: rgba(0, 0, 0, .5);
  border: 1px solid #0f0;
}

// Example of individual selectors getting their own lines (for error reporting)
.multiple,
.classes,
.get-new-lines {
  display: block;
}

// Avoid unnecessary shorthand declarations
.not-so-good {
  margin: 0 0 20px;
}
.good {
  margin-bottom: 20px;
}