Skip to content
GitLab
Switch branch/tag
Find file Normal viewHistoryPermalink
reboot.md 9.65 KB
Newer Older
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
1 
---
Mark Otto's avatar
Massive cleanup    
Mark Otto committed
2 
layout: docs
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
3 
title: Reboot
Mark Otto's avatar
docs rearrange    
Mark Otto committed
4 
group: content
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
5
6 
---
Mark Otto's avatar
editing intro    
Mark Otto committed
7 
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.
Mark Otto's avatar
more reboot updates    
Mark Otto committed
8
9 

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.
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
10
Mark Otto's avatar
add markdown toc stuff    
Mark Otto committed
11
12
13
14
15 
## Contents

* Will be replaced with the ToC, excluding the "Contents" header
{:toc}
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
16
17 
## Approach
Mark Otto's avatar
more reboot updates    
Mark Otto committed
18
19 
Here are our guidelines and reasons for choosing what to override in Reboot:
Mark Otto's avatar
more reboot edits    
Mark Otto committed
20 
- Update some browser default values to use `rem`s instead of `em`s for scalable component spacing.
Mark Otto's avatar
more reboot updates    
Mark Otto committed
21
22
23
24
25 
- 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 minimal, using `inherit` whenever possible.

## Page defaults
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
26
Mark Otto's avatar
more reboot updates    
Mark Otto committed
27 
The `<html>` and `<body>` elements are updated to provide better page-wide defaults. More specifically:
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
28
Mark Otto's avatar
more reboot updates    
Mark Otto committed
29
30
31
32 
- 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`.
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
33
Mark Otto's avatar
nav and typo    
Mark Otto committed
34 
## Headings and paragraphs
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105 

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>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
106
107
108
109
110
111
112
113
114
115
116
117
118
119 
## 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>
.element {
  margin-bottom: 1rem;
}
</pre>
{% endmarkdown %}
</div>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
120
121 
## Tables
Mark Otto's avatar
clarify some docs, improve layout    
Mark Otto committed
122 
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](/components/tables/).
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
123
124
125
126 

<div class="bd-example">
  <table>
    <caption>
Chris Rebert's avatar
reboot.md: fix typo    
Chris Rebert committed
127 
      This is an example table, and this is its caption to describe the contents.
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159 
    </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>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
160 
## Forms
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
161
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
162 
Various form elements have been rebooted for simpler base styles. Here are some of the most notable changes:
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
163
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
164 
- `<fieldset>`s have no borders, padding, or margin so they can be easily used as wrappers for individual inputs or groups of inputs.
Mark Otto's avatar
clarify some docs, improve layout    
Mark Otto committed
165 
- `<legend>`s, like fieldsets, have also been restyled to be displayed as a heading of sorts.
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
166
167
168 
- `<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 resizeble vertically as horizontal resizing often "breaks" page layout.
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
169
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
170 
These changes, and more, are demonstrated below.
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
171
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
172 
<form class="bd-example">
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197 
  <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>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
198 
    <p>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
199
200
201
202 
      <label>
        <input type="checkbox" value="">
        Check this checkbox
      </label>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
203 
    </p>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
204
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
205 
    <p>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
206
207
208
209
210
211
212
213
214
215
216
217 
      <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>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
218 
    </p>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
219
220
221 

    <p>
      <label for="textarea">Example textarea</label>
Mark Otto's avatar
Merge branch 'v4' of https://github.com/twbs/derpstrap into v4    
Mark Otto committed
222 
      <textarea id="textarea" rows="3"></textarea>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
223
224
225 
    </p>

    <p>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
226 
      <label for="time">Example temporal</label>
Mark Otto's avatar
Merge branch 'v4' of https://github.com/twbs/derpstrap into v4    
Mark Otto committed
227 
      <input type="datetime" id="time">
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
228
229
230 
    </p>

    <p>
Mark Otto's avatar
Merge branch 'v4' of https://github.com/twbs/derpstrap into v4    
Mark Otto committed
231
232 
      <label for="output">Example output</label>
      <output name="result" id="output">100</output>
Mark Otto's avatar
start stubbing out a new reboot section and file  
Mark Otto committed
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247 
    </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>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
248
249
250
251
252 

## Misc elements

### Address
Mark Otto's avatar
remove some typography docs from that page because they're covered in the reboot    
Mark Otto committed
253 
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>`.
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
254
255
256
257 

<div class="bd-example">
  <address>
    <strong>Twitter, Inc.</strong><br>
Mark Otto's avatar
Merge branch 'master' into v4m    
Mark Otto committed
258
259 
    1355 Market St, Suite 900<br>
    San Francisco, CA 94103<br>
Mark Otto's avatar
More reboot work, commenting out things that have been moved over    
Mark Otto committed
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286 
    <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>
    <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 the amongst paragraph text.

<div class="bd-example">
  Nulla <abbr title="attribute">attr</abbr> vitae elit libero, a pharetra augue.
</div>