Very Lightweight

1. Butter Cake

Butter Cake is a lightweight CSS framework which helps web developers create responsive, flexible mobile first web applications in an easy way, and built using Sass. Official Website

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2. Pure

Set of small, responsive CSS modules that you can use in every web project. Official Website

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3. Milligram

A minimalist CSS framework Official Website

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4. Picnic CSS

Lightweight and beautiful library Official Website

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