Bootstrap v4.0.0-beta.2 发布了，Bootstrap是快速开发Web应用程序的前端工具包。它是一个CSS和HTML的集合，它使用了最新的浏览器技术，给你的Web开发提供了时尚的版式，表单，buttons，表格，网格系统等等。

此次更新的亮点有：

• Improved Sass map customization with #23260. With this change, it's now possible to override specific key value pairs instead of resetting the entire map, ideal for color scheme customization.

• Restored grid .offset- modifiers in #23445. Originally our intent was to supplement this with our margin utilities, but we underestimated the appeal of fixed number column offsets.

• Remove unnecessary color from .badge, and it's associated $badge-color variable, in #23529.

• Rename grayscale function to gray to avoid breaking CSS native grayscale filter in #23579.

• Renamed .table-inverse, .thead-inverse, and .thead-default to .*-dark and .*-light, matching our color schemes used elsewhere in #23560.

• Responsive tables now generate classes for each grid breakpoint, meaning we've added .table-responsive-{sm,md,lg,xl} to the already present .table-responsive. You might need to adjust your usage depending on when you want a table to resize. See #22804.

• Include two new dist files which contain Popper.js inside bootstrap.bundle.js and bootstrap.bundle.min.js. See #23735.

• Dropped support for Bower as they've deprecated the package manager. See #23568.

• Switched breadcrumbs from float to flexbox in #23683.

• Added new CSS variables in #23761.

• Switched to Stylelint in #23572.

• New Theming page in the docs from #23611

• #23943: Changed the color-yiq from a mixin that included the color property to a function that returns a value, allowing you to use it for any CSS property. For example, instead of color-yiq(#000), you'd write color: color-yiq(#000);.

• New and improved theming in #24429.

完整内容请查看。

下载地址：

• bootstrap-4.0.0-beta.2-dist.zip

• Source code (zip)

• Source code (tar.gz)