About

This CSS Beautifier & Optimizer is an advanced parsing engine designed for front-end architects and developers working with legacy or minified stylesheets. Unlike simple regex-based formatters, this tool utilizes a recursive descent parser to construct an Abstract Syntax Tree (AST) of your CSS. This allows for context-aware operations such as safe property sorting (grouping vendor prefixes), intelligent nesting (converting flat CSS to SCSS/LESS), and granular syntax repair.

Clean code is not merely aesthetic; it is a prerequisite for maintainability and scalability. In large-scale applications, CSS entropy increases over time, leading to specificity wars and redundant declarations. This tool reverses that entropy, strictly enforcing consistency across indentation, spacing, and property ordering, reducing the cognitive load required to read and debug complex stylesheets.

Formulas

The core logic treats a CSS Rule R as a tuple containing a Selector Set S and a Declaration Block D. The optimization process opt transforms the input string I into an ordered structure.

{

R ∈ CSS ⇔ R = SDsort(D) &implies; ∀p_i,p_j ∈ D : key(p_i) ≤ key(p_j)

When converting to SCSS (Nesting), we analyze the specificity and descendant combinators. If selector S_B is a strict descendant of S_A (denoted S_A ⊃ S_B), we nest the rule.

nest(S_A, S_B) = TRUE if S_B = S_A + " " + S_child

Reference Data

CSS Unit	Type	Definition	Conversion Base (approx)
px	Absolute	Pixel (Screen logical unit)	1px = 196th of 1in
em	Relative	Relative to parent font-size	n × parent size
rem	Relative	Relative to root element (html)	n × root size
vw	Viewport	1% of Viewport Width	1vw = 0.01 × w_screen
vh	Viewport	1% of Viewport Height	1vh = 0.01 × h_screen
%	Relative	Percentage of containing block	Context dependent
ch	Relative	Width of the character "0"	Font dependent
vmin	Viewport	Min(vw, vh)	min(w, h) ÷ 100
deg	Angle	Degrees	360deg = 1 turn
s	Time	Seconds	1000ms

Frequently Asked Questions

Yes. The parser identifies all modern CSS3+ properties, including complex Grid template areas and Flexbox alignments. It does not alter values, only the formatting and indentation structure surrounding them.

Standard alphabetical sorting breaks CSS functionality if vendor prefixes (e.g., -webkit-, -moz-) are separated from their standard property. Our "Safe Sort" algorithm strips the prefix before comparing, ensuring that "-webkit-transform" stays immediately adjacent to "transform".

Yes. The "Fix Syntax" option actively scans for missing semicolons at the end of declaration blocks and automatically closes unclosed curly braces at the end of the file, preventing common cascade errors.

Beautify expands the code into a human-readable format with proper indentation (Tabs/Spaces). Minify removes all unnecessary whitespace, comments, and newlines to reduce file size for production environments.