mirror of
https://github.com/mdbootstrap/mdb-ui-kit.git
synced 2024-11-30 13:33:43 +03:00
329 lines
14 KiB
Markdown
329 lines
14 KiB
Markdown
---
|
||
layout: docs
|
||
title: Reboot
|
||
group: content
|
||
redirect_from: "/content/"
|
||
---
|
||
|
||
[//]: # DO NOT EDIT IT WILL BE OVERWRITTEN - copy of bootstrap documentation generated by grunt docs-copy-bootstrap-docs
|
||
|
||
{% callout info %}
|
||
**Bootstrap Reference Documentation**
|
||
This is reference documentation from <a href="http://getbootstrap.com">Bootstrap</a>.
|
||
It is being rendered with Material Design for Bootstrap to demonstrate default styling.
|
||
See addons(TODO: add link) for additional Material Design elements.
|
||
{% endcallout %}
|
||
|
||
|
||
|
||
Part of Bootstrap's job is to provide an elegant, consistent, and simple baseline to build upon. We use Reboot, a collection of element-specific CSS changes in a single file, to kickstart that.
|
||
|
||
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.
|
||
|
||
## Contents
|
||
|
||
* Will be replaced with the ToC, excluding the "Contents" header
|
||
{:toc}
|
||
|
||
## Approach
|
||
|
||
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.
|
||
- A base `font-size: 16px` is declared on the `<html>` and `font-size: 1rem` on the `<body>` for easy responsive type-scaling via media queryies.
|
||
- 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`.
|
||
|
||
## 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.
|
||
|
||
<div class="bd-example">
|
||
{% markdown %}
|
||
# h1 heading
|
||
Curabitur blandit tempus porttitor. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
|
||
|
||
## h2 heading
|
||
Curabitur blandit tempus porttitor. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
|
||
|
||
### h3 heading
|
||
Curabitur blandit tempus porttitor. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
|
||
|
||
#### h4 heading
|
||
Curabitur blandit tempus porttitor. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
|
||
|
||
##### h5 heading
|
||
Curabitur blandit tempus porttitor. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
|
||
|
||
###### h6 heading
|
||
Curabitur blandit tempus porttitor. Aenean eu leo quam. Pellentesque ornare sem lacinia quam venenatis vestibulum.
|
||
{% endmarkdown %}
|
||
</div>
|
||
|
||
## 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 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, `<selects>`s, `<textareas>`s, and `<buttons>`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" 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:#">first.last@example.com</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](http://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 IE9-10, 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 }}/components/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 currently iOS Safari (and any other iOS WebView-based browser) – though this is likely to change in iOS 10, see [WebKit bug #150604](https://bugs.webkit.org/show_bug.cgi?id=150604) – and IE11 on Windows Phone 8.1.
|
||
|
||
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 iOS, the currently 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](http://patrickhlauke.github.io/touch/tests/results/#suppressing-300ms-delay).
|