IMPORTANT NOTE: Read the NEW Bootstrap 4 “How to use SCSS Mixins” post here. Things like CSS grids should remain behind the curtain. No one really needs to know how it works, or why. Until you have a broken design or something complex and you can’t figure out why your spacing, margins, paddings etc are all messed up. It can be a real pain, especially when you are generating content dynamically in
![The Subtle Magic Behind Why the Bootstrap 3 Grid Works | Experience Design at Hello Erik](https://cdn-ak-scissors.b.st-hatena.com/image/square/c3d7c6db961a53df3ce302dc9016967a67b81813/height=288;version=1;width=512/http%3A%2F%2Fwww.helloerik.com%2Fwp-content%2Fuploads%2Fimage-1.png)