Learn CSS variables for design systems, theme switching, responsive spacing, reusable components, and animation tuning.
CSS Variables & Custom Properties | Theming & Reusable Styles
CSS Variables, also called Custom Properties , completely change how we write scalable and maintainable CSS. They allow you to store values once and reuse them everywhere, just like variables in programming languages. This guide explains CSS Variables from real-world usage point of view: theming, dynamic styles, layout control, and component-based design with clear micro explanations and live examples. What are CSS Variables? CSS Variables are reusable values defined using the --variable-name syntax and accessed using var() . Info!
CSS Variables live in the browser, not at build time like Sass variables. This means they can change dynamically.
1. Declaring CSS Variables Variables are usually declared inside :root so they are globally available. ✏️ Edit ▶ Run <div class="card">Primary Card</div>
<style>
:root {
--primary-color: #6366f1;
--radius: 14px;
}
.card {
padding: 20px;
background: var(--primary-color);
color: white;
border-radius: var(--radius)…
