軟件簡介
Bootstrap是Twitter推出的一個開源的用于前端開發的工具包。它由Twitter的設計師Mark Otto和Jacob Thornton合作開發，是一個CSS/HTML框架。Bootstrap提供了優雅的HTML和CSS規范，它即是由動態CSS語言Less寫成，與CSS框架Blueprint存在很多相似之處。Bootstrap一經推出后頗受歡迎，一直是GitHub上的熱門開源項目，包括NASA的MSNBC（微軟全國廣播公司）的Breaking News都使用了該項目。
Bootstrap 發布了一個新的大版本，解決了大量的 bug，改進了靈活性和持續性，引入一些很棒的新特性。
主要包括：
- Submenu support on dropdowns. We avoided this for some time as we thought it would unnecessarily complicate things, but we've backtracked on that and opted to add them in. See the docs for more info.
- Affix JavaScript plugin. Make anything stick to the top of the viewport as you scroll with our newest plugin, built to power our new docs navigation.
- Block level buttons. Add .btn-block to a button to make it full-width.
- State classes on table rows. Better convey success, warning, and error messages in tables.
- Improved disabled states on navs and dropdowns. Where by "improve" we mean actually present—just add .disabled to the li.
- The navbar component is now white by default, with an optional class to darken it. In order to have two options for the navbar, light and dark, we needed to have better defaults. Having a lighter default navbar means fewer lines of code as we don't need to override anything for the basic navbar functionality and the override it again to restore the default styles. Missing the black? Just add .navbar-inverse to get the dark gray navbar back.
- Improved prepended and appended inputs. No need to place the input and .add-on on the same line of code (sorry about that by the way). Break them up as you like and they'll still stick together with some crafty font-size working.
- New base font-size and line-height. 13px/18px is out, 14px/20px is in. This also has changed the size, line-height, and margin of our heading elements, buttons, and more.
- Added variable for navbar collapse trigger point. Instead of a fixed pixel width of 980pxfor triggering the collapsed navbar, we now use a variable so you can customize it for your projects.
- Fluid grid offsets. Thanks to our contributors, the fluid grid now has offset support to match our fixed (pixel) grid.
- Fluid grid system variables are no longer fixed percentages. Instead, they are calculated in LESS with percentage() based on the default, fixed-width grid variables. Math!
- Removed LESS docs page. We will no longer document variables and mixins in two places—rewriting that stuff was painful and took too much time. Instead, just checkout the .less files.