Bootstrap v4.0.0-alpha.5 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。

值得关注的更新：

Highlights

• Breakpoint specific grid gutters are here!

• Update the grid system so containers use width alongside a max-width: 100% for more durable layouts, fix the sm breakpoint and container dimension mismatch, and change the lg breakpoint width from 940px to 960px.

• Update utilities across the board, simplifying the margin and padding syntax (e.g., now mx-autoinstead of m-x-auto), separating background and color utilities for more explicit styling, renamed .img-rounded and .img-circle to .rounded and .rounded-circle, and removed display: blockfrom .img-fluid.

• Added new vertical alignment utilities.

• Updated development dependencies, so be sure to update to the latest Bundler and npm versions with gem install bundler, bundle update, and npm install.

• More customizable custom form controls with embedded SVGs and Sass variables.

• Brand new navbar toggler control featuring an SVG background-image.

• Fixed bug in our flexbox grid where columns didn't properly collapse at lower breakpoints.

• Removed momentum scrolling on modals for now due to an iOS 9-10 bug.

• Dozens of documentation updates and bug fixes.

CSS

• #17194, #20874: Ensure selects and inputs match their heights with .form-control.

• #17481: Add breakpoint-specific gutters to grid system.

• #18020: Improved custom checkbox and radio alignment.

• #18726, #19048: Add a margin-bottom: 0; to .card-header for use with headings.

• #19784, #20701: Improve units in dropdown components and remove margin-bottom from .dropdown-header.

• #19842 , #19847: Add .text-gray-dark utility class.

• #19926: Add .h-100 utility.

• #20118, #20700: Allow customization of custom form control background-image SVGs.

• #20234, #20329: Update navbar toggler to include a background SVG image for leaner markup and decently flexible styling.

• #20298, #20784: Remove margin-bottom on <label>-based buttons in button groups.

• #20395, #20873: Fix double border on items in flush list groups.

• #20428: Update to Normalize.css 4.2.0 to fix overflow problem on selects (#20384 and #20779).

• #20435, #20436: Add a couple !default flags to form CSS and update .form-control:focus to use proper box-shadow mixin.

• #20566, #20768: Restore collapse styles for table rows and table bodies.

• #20560, #20667: Update card images to use .img-fluid when appropriate, and fix rounded corner blemishes by using some calc() magic.

• #20654: Restore the display: inline-block on cards in columns to prevent cards from breaking across columns.

• #20684: Update ton of utilities for more explicit styling and better naming.

• #20733, #20869: Fix static form control sizing.

• #20752, #20868: Fix input groups width in inline forms.

• #20799, #20826: Apply same styling of disabled checks to disabled inline checks.

• #20803: Remove -webkit-overflow-scrolling: touch; due to an iOS Safari bug.

• #20810, #20874: Ensure the height of custom selects is maintained in IE/Edge.

• #20821: Update print styles borrowed from h5bp (fixes crash in IE11)

• #20829: Fix flexbox grid collapsing on lower breakpoints.

• #20865: Various grid updates to make containers use width and max-width, change lg breakpoint from 940px to 960px (cleanly divisible by 12), and fix mismatched sm breakpoint and container dimensions.

• #20866, #20932: Add vertical-alignment utilities.

• #20872: Updates to the form validation CSS and docs to show proper label styling, fix broken success icon, and implement a proper :focus state.

• #20933: Two variables now control the alert padding.

JS

• #17238: Tooltip and popover arrows are now generated via CSS.

• #17555, #17568: Fix issue where collapse plugin would leave an inline style of height: 0 after finishing the collapse animation.

• #17611, #17614: Change destroy to dispose for tooltip in _JQueryInterface.

Docs

• #16941, #19920: Document ability to add custom HTML in tooltips.

• #17159: Update collapse accordion example to use card component.

• #18437, #20825: Add social meta tags to the docs (e.g., for Twitter cards).

• #19287: Fix rendering of Examples overview page in the docs.

• #19409: Document modal focus option.

• #19466, #20697: Document the flexbox order utility classes.

• #19796, #20696: Update tooltip placement docs to remove mention of auto as it's no longer supported.

• #20214, #20247, #20695: Don't override border-radius on radio inputs.

• #20497, #20699: Document that all table styles are inherited.

• #20550, #20871: Document .bg-faded.

• #20557: Update tons of links to https and fix other broken links.

• #20600, #20870: Fix laggy collapse animations by ensuring .collapse elements have no padding on them.

• #20655: Update Reboot's font stack docs to match our CSS.

• #20646: Update font-size docs for our headings.

• #20678: Split out the Utilities docs from Components section and give each set of utilities their own page.

• #20688, #20864: Docs typo for grid dimensions.

• #20692, #20694: Fix integrity attributes on CDN assets.

• #20800, #20816: Remove the $ from the bash commands in docs.

• #20878: Update downloads page to include compiled, source, and CDN options.

Build tools

• #20446: Updated Hound and linting warnings.

• #20555: Upgrade devDependencies across the board.

• #20915: Change SauceLabs iPhone test to use Appium so builds pass again.

Packaging

• #18292, #20682: Provide compiled flex, grid, and Reboot dist stylesheets.

该版本其他更新：

• 新的 CSS 包

• Grid 升级

• 整改公共单元

• 导航栏升级

点此查看完整更新内容

发行说明及下载地址