MG Software.
HomeAboutServicesPortfolioBlogCalculator
Contact Us
  1. Home
  2. /Knowledge Base
  3. /What is CSS? - Definition & Meaning

What is CSS? - Definition & Meaning

Learn what CSS (Cascading Style Sheets) is and how it defines the visual style and layout of web pages.

CSS (Cascading Style Sheets) is a stylesheet language that defines the presentation of HTML documents: colors, fonts, spacing, layout and responsive behavior. CSS separates structure (HTML) from styling and is the standard for web styling.

What is What is CSS? - Definition & Meaning?

CSS (Cascading Style Sheets) is a stylesheet language that defines the presentation of HTML documents: colors, fonts, spacing, layout and responsive behavior. CSS separates structure (HTML) from styling and is the standard for web styling.

How does What is CSS? - Definition & Meaning work technically?

CSS uses selectors, properties and values. Cascading determines which rules take priority. Modern CSS includes Flexbox, Grid, Custom Properties (variables), media queries for responsive design, and animations. Preprocessors (Sass, Less) and frameworks (Tailwind, styled-components) extend CSS. CSS-in-JS combines styling with component logic in React. Critical CSS and tree-shaking optimize load performance.

How does MG Software apply What is CSS? - Definition & Meaning in practice?

MG Software uses Tailwind CSS for fast, consistent UI development. We combine utility-first CSS with design tokens for scalable design systems. For complex animations and theming we use CSS Custom Properties.

What are some examples of What is CSS? - Definition & Meaning?

  • An e-commerce site with responsive grid layout and dark mode via CSS Custom Properties, displaying correctly on all devices.
  • A SaaS dashboard with Tailwind where design tokens (colors, spacing) are centrally managed and reusable.
  • A marketing landing page with CSS animations for scroll-triggered effects and micro-interactions for better UX.

Related terms

reactnextjstypescriptdevtools

Further reading

Knowledge BaseWhat is Tailwind CSS? - Definition & MeaningWhat is React? - Definition & MeaningBest CSS Frameworks 2026CSS-in-JS vs CSS Modules: Which Should You Choose?

Related articles

What is a CSS Framework? - Explanation & Meaning

Learn what a CSS framework is, how Tailwind CSS and Bootstrap work, the difference between utility-first and component-based approaches, and modern options available.

What is Tailwind CSS? - Definition & Meaning

Learn what Tailwind CSS is, how utility-first CSS works, and why it is the standard for fast, consistent styling.

Best CSS Frameworks 2026

Discover the best CSS frameworks of 2026. Compare TailwindCSS v4, UnoCSS, Panda CSS, Vanilla Extract, and StyleX on performance, developer experience, and scalability.

CSS-in-JS vs CSS Modules: Which Should You Choose?

Compare CSS-in-JS and CSS Modules on component styling, performance and maintainability. Discover which approach fits your frontend best.

Frequently asked questions

SCSS (Sass) is a CSS preprocessor that adds variables, nesting, mixins and functions. The code is compiled to plain CSS. SCSS makes large stylesheets more manageable; Tailwind and CSS-in-JS are alternatives that do not require a preprocessor.
CSS Custom Properties (or CSS variables) are developer-defined values (e.g. --primary-color: #0070f3) that can be reused in the stylesheet. They support theming (e.g. dark mode) and runtime updates via JavaScript.
Use critical CSS for above-the-fold content, tree-shake unused utilities (e.g. with PurgeCSS/Tailwind), and minimize reflows by preferring transform and opacity for animations over layout properties.

What is the difference between CSS and SCSS?

SCSS (Sass) is a CSS preprocessor that adds variables, nesting, mixins and functions. The code is compiled to plain CSS. SCSS makes large stylesheets more manageable; Tailwind and CSS-in-JS are alternatives that do not require a preprocessor.

What are CSS Custom Properties?

CSS Custom Properties (or CSS variables) are developer-defined values (e.g. --primary-color: #0070f3) that can be reused in the stylesheet. They support theming (e.g. dark mode) and runtime updates via JavaScript.

How do I optimize CSS for performance?

Use critical CSS for above-the-fold content, tree-shake unused utilities (e.g. with PurgeCSS/Tailwind), and minimize reflows by preferring transform and opacity for animations over layout properties.

We work with this daily

The same expertise you're reading about, we put to work for clients.

Discover what we can do

Related articles

What is a CSS Framework? - Explanation & Meaning

Learn what a CSS framework is, how Tailwind CSS and Bootstrap work, the difference between utility-first and component-based approaches, and modern options available.

What is Tailwind CSS? - Definition & Meaning

Learn what Tailwind CSS is, how utility-first CSS works, and why it is the standard for fast, consistent styling.

Best CSS Frameworks 2026

Discover the best CSS frameworks of 2026. Compare TailwindCSS v4, UnoCSS, Panda CSS, Vanilla Extract, and StyleX on performance, developer experience, and scalability.

CSS-in-JS vs CSS Modules: Which Should You Choose?

Compare CSS-in-JS and CSS Modules on component styling, performance and maintainability. Discover which approach fits your frontend best.

MG Software
MG Software
MG Software.

MG Software builds custom software, websites and AI solutions that help businesses grow.

© 2026 MG Software B.V. All rights reserved.

NavigationServicesPortfolioAbout UsContactBlogCalculator
ResourcesKnowledge BaseComparisonsAlternativesExamplesToolsRefront
LocationsHaarlemAmsterdamThe HagueEindhovenBredaAmersfoortAll locations
IndustriesLegalEnergyHealthcareE-commerceLogisticsAll industries