Atomic CSS (also historically called Functional CSS) shares conceptual parallels with functional programming. The post explores three core FP principles — pure functions, immutability, and function composition — and maps each to Atomic CSS equivalents. Purity in CSS means element styles depend only on their own classes, not on context or parent selectors. Immutability means utility classes don't override each other, unlike BEM modifiers that mutate base styles. Composition means combining small single-purpose utilities to achieve complex styling, just as FP composes simple functions. Examples use the mlut framework alongside Tailwind CSS references to illustrate each concept.
Table of contents
PrerequisitesWhat We'll Cover:The Basic Principles of Functional ProgrammingHow the Principles of FP Meet Their Incarnation in Atomic CSSConclusionSort: