document migration for grid system /cc #17593

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Mark Otto 2016-02-06 13:02:59 -08:00
parent fb4f5f0bf1
commit ce81dd8537
1 changed files with 10 additions and 1 deletions

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@ -22,11 +22,20 @@ Here are the big ticket items you'll want to be aware of when moving from v3 to
### Global changes
- Switched from [Less](http://lesscss.org/) to [Sass](http://sass-lang.com/) for our source CSS files.
- Switched from `px` to `rem` as our primary CSS unit, though pixels are still used for media queries and more as viewports are not affected by type size.
- Switched from `px` to `rem` as our primary CSS unit, though pixels are still used for media queries and grid behavior as viewports are not affected by type size.
- Global font-size increased from `14px` to `16px`.
- Added a new grid tier for ~`480px` and below.
- Replaced the separate optional theme with configurable options via SCSS variables (e.g., `$enable-gradients: true`).
### Grid system
- Added support for flexbox (set `$enable-flex: true` and recompile) in the grid mixins and predefined classes.
- As part of flexbox, included support for vertical and horizontal alignment classes.
- Overhauled grid mixins to merge `make-col-span` into `make-col` for a singular mixin.
- Added a new `sm` grid tier below `768px` for more granular control. We now have `xs`, `sm`, `md`, `lg`, and `xl`. This also means every tier has been bumped up one level (so `.col-md-6` in v3 is now `.col-lg-6` in v4).
- Changed grid system media query breakpoints and container widths to account for new grid tier and ensure columns are evenly divisible by `12` at their max width.
- Grid breakpoints and container widths are now handled via Sass maps instead of a handful of separate variables. These replace the `@screen-*` variables entirely and allow you to fully customize the grid tiers.
### Components
- Dropped panels, thumbnails, and wells for a new all-encompassing component, cards.