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| author | Mark Otto <[email protected]> | 2017-05-28 22:50:57 -0700 |
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| committer | Mark Otto <[email protected]> | 2017-05-29 23:32:28 -0700 |
| commit | 3e76d6565603fafa2c85ad81d7b6345c4e279c72 (patch) | |
| tree | fad0aa6a4a70cafb4a803bd920d6ae2fa44dc466 /docs/content/reboot.md | |
| parent | 32153eb7cba316b873e82cd7b9362c92ca00eddf (diff) | |
| download | bootstrap-3e76d6565603fafa2c85ad81d7b6345c4e279c72.tar.xz bootstrap-3e76d6565603fafa2c85ad81d7b6345c4e279c72.zip | |
Rearrange all the docs to allow for a docs/major.minor/ setup
Diffstat (limited to 'docs/content/reboot.md')
| -rw-r--r-- | docs/content/reboot.md | 359 |
1 files changed, 0 insertions, 359 deletions
diff --git a/docs/content/reboot.md b/docs/content/reboot.md deleted file mode 100644 index a9dd6a6d0..000000000 --- a/docs/content/reboot.md +++ /dev/null @@ -1,359 +0,0 @@ ---- -layout: docs -title: Reboot -description: Reboot, a collection of element-specific CSS changes in a single file, kickstart Bootstrap to provide an elegant, consistent, and simple baseline to build upon. -group: content -redirect_from: "/content/" -toc: true ---- - -## Approach - -Reboot builds upon Normalize, providing many HTML elements with somewhat opinionated styles using only element selectors. Additional styling is done only with classes. For example, we reboot some `<table>` styles for a simpler baseline and later provide `.table`, `.table-bordered`, and more. - -Here are our guidelines and reasons for choosing what to override in Reboot: - -- Update some browser default values to use `rem`s instead of `em`s for scalable component spacing. -- Avoid `margin-top`. Vertical margins can collapse, yielding unexpected results. More importantly though, a single direction of `margin` is a simpler mental model. -- For easier scaling across device sizes, block elements should use `rem`s for `margin`s. -- Keep declarations of `font`-related properties to a minimum, using `inherit` whenever possible. - -## Page defaults - -The `<html>` and `<body>` elements are updated to provide better page-wide defaults. More specifically: - -- The `box-sizing` is globally set on every element—including `*:before` and `*:after`, to `border-box`. This ensures that the declared width of element is never exceeded due to padding or border. - - No base `font-size` is declared on the `<html>`, but `16px` is assumed (the browser default). `font-size: 1rem` is applied on the `<body>` for easy responsive type-scaling via media queries while respecting user preferences and ensuring a more accessible approach. -- The `<body>` also sets a global `font-family` and `line-height`. This is inherited later by some form elements to prevent font inconsistencies. -- For safety, the `<body>` has a declared `background-color`, defaulting to `#fff`. - -## Native font stack - -The default web fonts (Helvetica Neue, Helvetica, and Arial) have been dropped in Bootstrap 4 and replaced with a "native font stack" for optimum text rendering on every device and OS. Read more about [native font stacks in this *Smashing Magazine* article](https://www.smashingmagazine.com/2015/11/using-system-ui-fonts-practical-guide/). - -{% highlight sass %} -$font-family-sans-serif: - // Safari for OS X and iOS (San Francisco) - -apple-system, - // Chrome >= 56 for OS X (San Francisco), Windows, Linux and Android - system-ui, - // Chrome < 56 for OS X (San Francisco) - BlinkMacSystemFont, - // Windows - "Segoe UI", - // Android - "Roboto", - // Basic web fallback - "Helvetica Neue", Arial, sans-serif !default; -{% endhighlight %} - -This `font-family` is applied to the `<body>` and automatically inherited globally throughout Bootstrap. To switch the global `font-family`, update `$font-family-base` and recompile Bootstrap. - -## Headings and paragraphs - -All heading elements—e.g., `<h1>`—and `<p>` are reset to have their `margin-top` removed. Headings have `margin-bottom: .5rem` added and paragraphs `margin-bottom: 1rem` for easy spacing. - -<table> - <thead> - <tr> - <th>Heading</th> - <th>Example</th> - </tr> - </thead> - <tbody> - <tr> - <td> - {% markdown %}`<h1></h1>`{% endmarkdown %} - </td> - <td><span class="h1">h1. Bootstrap heading</span></td> - </tr> - <tr> - <td> - {% markdown %}`<h2></h2>`{% endmarkdown %} - </td> - <td><span class="h2">h2. Bootstrap heading</span></td> - </tr> - <tr> - <td> - {% markdown %}`<h3></h3>`{% endmarkdown %} - </td> - <td><span class="h3">h3. Bootstrap heading</span></td> - </tr> - <tr> - <td> - {% markdown %}`<h4></h4>`{% endmarkdown %} - </td> - <td><span class="h4">h4. Bootstrap heading</span></td> - </tr> - <tr> - <td> - {% markdown %}`<h5></h5>`{% endmarkdown %} - </td> - <td><span class="h5">h5. Bootstrap heading</span></td> - </tr> - <tr> - <td> - {% markdown %}`<h6></h6>`{% endmarkdown %} - </td> - <td><span class="h6">h6. Bootstrap heading</span></td> - </tr> - </tbody> -</table> - -## Lists - -All lists—`<ul>`, `<ol>`, and `<dl>`—have their `margin-top` removed and a `margin-bottom: 1rem`. Nested lists have no `margin-bottom`. - -<div class="bd-example"> -{% markdown %} -* Lorem ipsum dolor sit amet -* Consectetur adipiscing elit -* Integer molestie lorem at massa -* Facilisis in pretium nisl aliquet -* Nulla volutpat aliquam velit - * Phasellus iaculis neque - * Purus sodales ultricies - * Vestibulum laoreet porttitor sem - * Ac tristique libero volutpat at -* Faucibus porta lacus fringilla vel -* Aenean sit amet erat nunc -* Eget porttitor lorem - -1. Lorem ipsum dolor sit amet -2. Consectetur adipiscing elit -3. Integer molestie lorem at massa -4. Facilisis in pretium nisl aliquet -5. Nulla volutpat aliquam velit -6. Faucibus porta lacus fringilla vel -7. Aenean sit amet erat nunc -8. Eget porttitor lorem -{% endmarkdown %} -</div> - -For simpler styling, clear hierarchy, and better spacing, description lists have updated `margin`s. `<dd>`s reset `margin-left` to `0` and add `margin-bottom: .5rem`. `<dt>`s are **bolded**. - -<div class="bd-example"> -{% markdown %} -<dl> - <dt>Description lists</dt> - <dd>A description list is perfect for defining terms.</dd> - <dt>Euismod</dt> - <dd>Vestibulum id ligula porta felis euismod semper eget lacinia odio sem.</dd> - <dd>Donec id elit non mi porta gravida at eget metus.</dd> - <dt>Malesuada porta</dt> - <dd>Etiam porta sem malesuada magna mollis euismod.</dd> -</dl> -{% endmarkdown %} -</div> - -## Preformatted text - -The `<pre>` element is reset to remove its `margin-top` and use `rem` units for its `margin-bottom`. - -<div class="bd-example"> -{% markdown %} -<pre> -.example-element { - margin-bottom: 1rem; -} -</pre> -{% endmarkdown %} -</div> - -## Tables - -Tables are slightly adjusted to style `<caption>`s, collapse borders, and ensure consistent `text-align` throughout. Additional changes for borders, padding, and more come with [the `.table` class]({{ site.baseurl }}/content/tables/). - -<div class="bd-example"> - <table> - <caption> - This is an example table, and this is its caption to describe the contents. - </caption> - <thead> - <tr> - <th>Table heading</th> - <th>Table heading</th> - <th>Table heading</th> - <th>Table heading</th> - </tr> - </thead> - <tbody> - <tr> - <td>Table cell</td> - <td>Table cell</td> - <td>Table cell</td> - <td>Table cell</td> - </tr> - <tr> - <td>Table cell</td> - <td>Table cell</td> - <td>Table cell</td> - <td>Table cell</td> - </tr> - <tr> - <td>Table cell</td> - <td>Table cell</td> - <td>Table cell</td> - <td>Table cell</td> - </tr> - </tbody> - </table> -</div> - -## Forms - -Various form elements have been rebooted for simpler base styles. Here are some of the most notable changes: - -- `<fieldset>`s have no borders, padding, or margin so they can be easily used as wrappers for individual inputs or groups of inputs. -- `<legend>`s, like fieldsets, have also been restyled to be displayed as a heading of sorts. -- `<label>`s are set to `display: inline-block` to allow `margin` to be applied. -- `<input>`s, `<select>`s, `<textarea>`s, and `<button>`s are mostly addressed by Normalize, but Reboot removes their `margin` and sets `line-height: inherit`, too. -- `<textarea>`s are modified to only be resizable vertically as horizontal resizing often "breaks" page layout. - -These changes, and more, are demonstrated below. - -<form class="bd-example"> - <fieldset> - <legend>Example legend</legend> - - <p> - <label for="input">Example input</label> - <input type="text" id="input" placeholder="Example input"> - </p> - - <p> - <label for="select">Example select</label> - <select id="select"> - <option value="">Choose...</option> - <optgroup label="Option group 1"> - <option value="">Option 1</option> - <option value="">Option 2</option> - <option value="">Option 3</option> - </optgroup> - <optgroup label="Option group 2"> - <option value="">Option 4</option> - <option value="">Option 5</option> - <option value="">Option 6</option> - </optgroup> - </select> - </p> - - <p> - <label> - <input type="checkbox" value=""> - Check this checkbox - </label> - </p> - - <p> - <label> - <input type="radio" name="optionsRadios" id="optionsRadios1" value="option1" checked> - Option one is this and that - </label> - <label> - <input type="radio" name="optionsRadios" id="optionsRadios2" value="option2"> - Option two is something else that's also super long to demonstrate the wrapping of these fancy form controls. - </label> - <label> - <input type="radio" name="optionsRadios" id="optionsRadios3" value="option3" disabled> - Option three is disabled - </label> - </p> - - <p> - <label for="textarea">Example textarea</label> - <textarea id="textarea" rows="3"></textarea> - </p> - - <p> - <label for="time">Example temporal</label> - <input type="datetime-local" id="time"> - </p> - - <p> - <label for="output">Example output</label> - <output name="result" id="output">100</output> - </p> - - <p> - <button type="submit">Button submit</button> - <input type="submit" value="Input submit button"> - <input type="button" value="Input button"> - </p> - - <p> - <button type="submit" disabled>Button submit</button> - <input type="submit" value="Input submit button" disabled> - <input type="button" value="Input button" disabled> - </p> - </fieldset> -</form> - -## Misc elements - -### Address - -The `<address>` element is updated to reset the browser default `font-style` from `italic` to `normal`. `line-height` is also now inherited, and `margin-bottom: 1rem` has been added. `<address>`s are for presenting contact information for the nearest ancestor (or an entire body of work). Preserve formatting by ending lines with `<br>`. - -<div class="bd-example"> - <address> - <strong>Twitter, Inc.</strong><br> - 1355 Market St, Suite 900<br> - San Francisco, CA 94103<br> - <abbr title="Phone">P:</abbr> (123) 456-7890 - </address> - - <address> - <strong>Full Name</strong><br> - <a href="mailto:#">[email protected]</a> - </address> -</div> - -### Blockquote - -The default `margin` on blockquotes is `1em 40px`, so we reset that to `0 0 1rem` for something more consistent with other elements. - -<div class="bd-example"> - <blockquote class="blockquote"> - <p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p> - <footer>Someone famous in <cite title="Source Title">Source Title</cite></footer> - </blockquote> -</div> - -### Inline elements - -The `<abbr>` element receives basic styling to make it stand out amongst paragraph text. - -<div class="bd-example"> - Nulla <abbr title="attribute">attr</abbr> vitae elit libero, a pharetra augue. -</div> - -## HTML5 `[hidden]` attribute - -HTML5 adds [a new global attribute named `[hidden]`](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/hidden), which is styled as `display: none` by default. Borrowing an idea from [PureCSS](https://purecss.io), we improve upon this default by making `[hidden] { display: none !important; }` to help prevent its `display` from getting accidentally overridden. While `[hidden]` isn't natively supported by IE10, the explicit declaration in our CSS gets around that problem. - -{% highlight html %} -<input type="text" hidden> -{% endhighlight %} - -{% callout warning %} -#### jQuery incompatibility - -`[hidden]` is not compatible with jQuery's `$(...).hide()` and `$(...).show()` methods. This could potentially change in jQuery 3, but we're not holding our breath. Therefore, we don't currently especially endorse `[hidden]` over other techniques for managing the `display` of elements. -{% endcallout %} - -To merely toggle the visibility of an element, meaning its `display` is not modified and the element can still affect the flow of the document, use [the `.invisible` class]({{ site.baseurl }}/utilities/invisible-content/) instead. - -## Click delay optimization for touch - -Traditionally, browsers on touchscreen devices have a delay of approximately 300ms between the end of a "tap" – the moment when a finger/stylus is lifted from screen – and the [`click` event](https://developer.mozilla.org/en-US/docs/Web/Events/click) being fired. This delay is necessary for these browsers to correctly handle "double-tap to zoom" gestures without prematurely triggering actions or links after the first "tap", but it can make your site feel slightly sluggish and unresponsive. - -Most mobile browsers automatically optimize away this 300ms delay for sites that use the `width=device-width` property as part of their [responsive meta tag]({{ site.baseurl }}/getting-started/introduction/#responsive-meta-tag) (as well as for sites that disable zooming, for instance with `user-scalable=no`, though this practice is strongly discouraged for accessibility and usability reasons). The biggest exceptions here are IE11 on Windows Phone 8.1, and iOS Safari (and any other iOS WebView-based browser) [prior to iOS 9.3](https://webkit.org/blog/5610/more-responsive-tapping-on-ios/). - -On touch-enabled laptop/desktop devices, IE11 and Microsoft Edge are currently the only browsers with "double-tap to zoom" functionality. As the [responsive meta tag]({{ site.baseurl }}/getting-started/introduction/#responsive-meta-tag) is ignored by all desktop browsers, using `width=device-width` will have no effect on the 300ms delay here. - -To address this problem in IE11 and Microsoft Edge on desktop, as well as IE11 on Windows Phone 8.1, Bootstrap explicitly uses the [`touch-action:manipulation` CSS property](https://developer.mozilla.org/en-US/docs/Web/CSS/touch-action) on all interactive elements (such as buttons and links). This property essentially disables double-tap functionality on those elements, eliminating the 300ms delay. - -In the case of old iOS versions (prior to 9.3), the suggested approach is to use additional scripts such as [FastClick](https://github.com/ftlabs/fastclick) to explicitly work around the delay. - -For further details, see the compatibility table for [suppressing 300ms delay for touchscreen interactions](https://patrickhlauke.github.io/touch/tests/results/#suppressing-300ms-delay). |