/
index.md
522 lines (396 loc) · 22.1 KB
/
index.md
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
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
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
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
160
161
162
163
164
165
166
167
168
169
170
171
172
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
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
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
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
---
title: Advanced form styling
slug: Learn/Forms/Advanced_form_styling
page-type: learn-module-chapter
---
{{LearnSidebar}}{{PreviousMenuNext("Learn/Forms/Styling_web_forms", "Learn/Forms/UI_pseudo-classes", "Learn/Forms")}}
In this article, we will see what can be done with CSS to style the types of form control that are more difficult to style — the "bad" and "ugly" categories. As we saw [in the previous article](/en-US/docs/Learn/Forms/Styling_web_forms), text fields and buttons are perfectly easy to style; now we will dig into styling the more problematic bits.
<table>
<tbody>
<tr>
<th scope="row">Prerequisites:</th>
<td>
A basic understanding of
<a href="/en-US/docs/Learn/HTML/Introduction_to_HTML">HTML</a> and
<a href="/en-US/docs/Learn/CSS/First_steps">CSS</a>.
</td>
</tr>
<tr>
<th scope="row">Objective:</th>
<td>
To understand what parts of forms are hard to style, and why; to learn
what can be done to customize them.
</td>
</tr>
</tbody>
</table>
To recap what we said in the previous article, we have:
**The bad**: Some elements are more difficult to style, requiring more complex CSS or some more specific tricks:
- Checkboxes and radio buttons
- [`<input type="search">`](/en-US/docs/Web/HTML/Element/input/search)
**The ugly**: Some elements can't be styled thoroughly using CSS. These include:
- Elements involved in creating dropdown widgets, including {{HTMLElement("select")}}, {{HTMLElement("option")}}, {{HTMLElement("optgroup")}} and {{HTMLElement("datalist")}}.
- [`<input type="color">`](/en-US/docs/Web/HTML/Element/input/color)
- Date-related controls such as [`<input type="datetime-local">`](/en-US/docs/Web/HTML/Element/input/datetime-local)
- [`<input type="range">`](/en-US/docs/Web/HTML/Element/input/range)
- [`<input type="file">`](/en-US/docs/Web/HTML/Element/input/file)
- {{HTMLElement("progress")}} and {{HTMLElement("meter")}}
Let's first talk about the [`appearance`](/en-US/docs/Web/CSS/appearance) property, which is pretty useful for making all of the above more stylable.
## appearance: controlling OS-level styling
In the previous article we said that historically, the styling of web form controls was largely taken from the underlying operating system, which is part of the problem with customizing the look of these controls.
The {{cssxref("appearance")}} property was created as a way to control what OS- or system-level styling was applied to web form controls. By far the most helpful value, and probably the only one you'll use, is `none`. This stops any control you apply it to from using system-level styling, as much as possible, and lets you build up the styles yourself using CSS.
For example, let's take the following controls:
```html
<form>
<p>
<label for="search">search: </label>
<input id="search" name="search" type="search" />
</p>
<p>
<label for="text">text: </label>
<input id="text" name="text" type="text" />
</p>
<p>
<label for="date">date: </label>
<input id="date" name="date" type="datetime-local" />
</p>
<p>
<label for="radio">radio: </label>
<input id="radio" name="radio" type="radio" />
</p>
<p>
<label for="checkbox">checkbox: </label>
<input id="checkbox" name="checkbox" type="checkbox" />
</p>
<p><input type="submit" value="submit" /></p>
<p><input type="button" value="button" /></p>
</form>
```
Applying the following CSS to them removes system-level styling.
```css
input {
appearance: none;
}
```
The following live example shows you what they look like in your system — default on the left, and with the above CSS applied on the right ([find it here also](https://mdn.github.io/learning-area/html/forms/styling-examples/appearance-tester.html) if you want to test it on other systems).
{{EmbedGHLiveSample("learning-area/html/forms/styling-examples/appearance-tester.html", '100%', 400)}}
In most cases, the effect is to remove the stylized border, which makes CSS styling a bit easier, but isn't really essential. In a couple of cases — search and radio buttons/checkboxes, it becomes way more useful. We'll look at those now.
### Taming search boxes
[`<input type="search">`](/en-US/docs/Web/HTML/Element/input/search) is basically just a text input, so why is `appearance: none;` useful here? The answer is that Safari search boxes have some styling restrictions — you can't adjust their `height` or `font-size` freely, for example.
This can be fixed using our friend `appearance: none;`, which disables the default appearance:
```css
input[type="search"] {
appearance: none;
}
```
In the example below, you can see two identical styled search boxes. The right one has `appearance: none;` applied, and the left one doesn't. If you look at it in Safari on macOS you'll see that the left one isn't sized properly.
{{EmbedGHLiveSample("learning-area/html/forms/styling-examples/search-appearance.html", '100%', 200)}}
Interestingly, setting border/background on the search field also fixes this problem. The following styled search doesn't have `appearance: none;` applied, but it doesn't suffer from the same problem in Safari as the previous example.
{{EmbedGHLiveSample("learning-area/html/forms/styling-examples/styled-search.html", '100%', 200)}}
> **Note:** You may have noticed that in the search field, the "x" delete icon, which appears when the value of the search is not null, disappears when the input loses focus in Edge and Chrome, but stays put in Safari. To remove via CSS, you can use `input[type="search"]:not(:focus, :active)::-webkit-search-cancel-button { display: none; }`.
### Styling checkboxes and radio buttons
Styling a checkbox or a radio button is tricky by default. The sizes of checkboxes and radio buttons are not meant to be changed with their default designs, and browsers react very differently when you try.
For example, consider this simple test case:
```html
<label
><span><input type="checkbox" name="q5" value="true" /></span> True</label
>
<label
><span><input type="checkbox" name="q5" value="false" /></span> False</label
>
```
```css
span {
display: inline-block;
background: red;
}
input[type="checkbox"] {
width: 100px;
height: 100px;
}
```
Different browsers handle the checkbox and span differently, often ugly ways:
| Browser | Rendering |
| ----------------------------------- | ------------------------------------------------------------------------------------------------------ |
| Firefox 71 (macOS) | ![Rounded corners and 1px light grey border](firefox-mac-checkbox.png) |
| Firefox 57 (Windows 10) | ![Rectangular corners with 1px medium grey border](firefox-windows-checkbox.png) |
| Chrome 77 (macOS), Safari 13, Opera | ![Rounded corner with 1px medium grey border](chrome-mac-checkbox.png) |
| Chrome 63 (Windows 10) | ![Rectangular borders with slightly greyish background instead of white.](chrome-windows-checkbox.png) |
| Edge 16 (Windows 10) | ![Rectangular borders with slightly greyish background instead of white.](edge-checkbox.png) |
#### Using appearance: none on radios/checkboxes
As we showed before, you can remove the default appearance of a checkbox or radio button altogether with {{cssxref('appearance')}}`:none;`. Let's take this example HTML:
```html
<form>
<fieldset>
<legend>Fruit preferences</legend>
<p>
<label>
<input type="checkbox" name="fruit" value="cherry" />
I like cherry
</label>
</p>
<p>
<label>
<input type="checkbox" name="fruit" value="banana" disabled />
I can't like banana
</label>
</p>
<p>
<label>
<input type="checkbox" name="fruit" value="strawberry" />
I like strawberry
</label>
</p>
</fieldset>
</form>
```
Now, let's style these with a custom checkbox design. Let's start by unstyling the original check boxes:
```css
input[type="checkbox"] {
appearance: none;
}
```
We can use the {{cssxref(":checked")}} and {{cssxref(":disabled")}} pseudo-classes to change the appearance of our custom checkbox as its state changes:
```css
input[type="checkbox"] {
position: relative;
width: 1em;
height: 1em;
border: 1px solid gray;
/* Adjusts the position of the checkboxes on the text baseline */
vertical-align: -2px;
/* Set here so that Windows' High-Contrast Mode can override */
color: green;
}
input[type="checkbox"]::before {
content: "✔";
position: absolute;
font-size: 1.2em;
right: -1px;
top: -0.3em;
visibility: hidden;
}
input[type="checkbox"]:checked::before {
/* Use `visibility` instead of `display` to avoid recalculating layout */
visibility: visible;
}
input[type="checkbox"]:disabled {
border-color: black;
background: #ddd;
color: gray;
}
```
You'll find out more about such pseudo-classes and more in the [next article](/en-US/docs/Learn/Forms/UI_pseudo-classes); the above ones do the following:
- `:checked` — the checkbox (or radio button) is in a checked state — the user has clicked/activated it.
- `:disabled` — the checkbox (or radio button) is in a disabled state — it cannot be interacted with.
You can see the live result:
{{EmbedGHLiveSample("learning-area/html/forms/styling-examples/checkboxes-styled.html", '100%', 200)}}
We've also created a couple of other examples to give you more ideas:
- [Styled radio buttons](https://mdn.github.io/learning-area/html/forms/styling-examples/radios-styled.html): Custom radio button styling.
- [Toggle switch example](https://mdn.github.io/learning-area/html/forms/toggle-switch-example/): A checkbox styled to look like a toggle switch.
If you view these checkboxes in a browser that doesn't support {{cssxref("appearance")}}, your custom design will be lost, but they will still look like checkboxes and be usable.
## What can be done about the "ugly" elements?
Now let's turn our attention to the "ugly" controls — the ones that are really hard to thoroughly style. In short, these are drop-down boxes, complex control types like [`color`](/en-US/docs/Web/HTML/Element/input/color) and [`datetime-local`](/en-US/docs/Web/HTML/Element/input/datetime-local), and feedback—oriented controls like {{HTMLElement("progress")}} and {{HTMLElement("meter")}}.
The problem is that these elements have very different default looks across browsers, and while you can style them in some ways, some parts of their internals are literally impossible to style.
If you are prepared to live with some differences in look and feel, you can get away with some simple styling to make sizing consistent, uniform styling of things like background-colors, and usage of appearance to get rid of some system-level styling.
Take the following example, which shows a number of the "ugly" form features in action:
{{EmbedGHLiveSample("learning-area/html/forms/styling-examples/ugly-controls.html", '100%', 750)}}
This example has the following CSS applied to it:
```css
body {
font-family: "Josefin Sans", sans-serif;
margin: 20px auto;
max-width: 400px;
}
form > div {
margin-bottom: 20px;
}
select {
appearance: none;
width: 100%;
height: 100%;
}
.select-wrapper {
position: relative;
}
.select-wrapper::after {
content: "▼";
font-size: 1rem;
top: 3px;
right: 10px;
position: absolute;
}
button,
label,
input,
select,
progress,
meter {
display: block;
font-family: inherit;
font-size: 100%;
margin: 0;
box-sizing: border-box;
width: 100%;
padding: 5px;
height: 30px;
}
input[type="text"],
input[type="datetime-local"],
input[type="color"],
select {
box-shadow: inset 1px 1px 3px #ccc;
border-radius: 5px;
}
label {
margin-bottom: 5px;
}
button {
width: 60%;
margin: 0 auto;
}
```
> **Note:** If you want to test these examples across a number of browsers simultaneously, you can [find it live here](https://mdn.github.io/learning-area/html/forms/styling-examples/ugly-controls.html) (also [see here for the source code](https://github.com/mdn/learning-area/blob/main/html/forms/styling-examples/ugly-controls.html)).
>
> Also bear in mind that we've added some JavaScript to the page that lists the files selected by the file picker, below the control itself. This is a simplified version of the example found on the [`<input type="file">`](/en-US/docs/Web/HTML/Element/input/file#examples) reference page.
As you can see, we've done fairly well at getting these to look uniform across modern browsers.
We've applied some global normalizing CSS to all the controls and their labels, to get them to size in the same way, adopt their parent font, etc., as mentioned in the previous article:
```css
button,
label,
input,
select,
progress,
meter {
display: block;
font-family: inherit;
font-size: 100%;
margin: 0;
box-sizing: border-box;
width: 100%;
padding: 5px;
height: 30px;
}
```
We also added some uniform shadow and rounded corners to the controls on which it made sense:
```css
input[type="text"],
input[type="datetime-local"],
input[type="color"],
select {
box-shadow: inset 1px 1px 3px #ccc;
border-radius: 5px;
}
```
On other controls like range types, progress bars, and meters they just add an ugly box around the control area, so it doesn't make sense.
Let's talk about some specifics of each of these types of control, highlighting difficulties along the way.
### Selects and datalists
In modern browsers, selects and datalists are generally not too bad to style provided you don't want to vary the look and feel too much from the defaults.
We've managed to get the basic look of the boxes looking pretty uniform and consistent. The datalist control is `<input type="text">` anyway, so we knew this wouldn't be a problem.
Two things are slightly more problematic. First of all, the select's "arrow" icon that indicates it is a dropdown differs across browsers. It also tends to change if you increase the size of the select box, or resize in an ugly fashion. To fix this in our example we first used our old friend `appearance: none` to get rid of the icon altogether:
```css
select {
appearance: none;
}
```
We then created our own icon using generated content. We put an extra wrapper around the control, because [`::before`](/en-US/docs/Web/CSS/::before)/[`::after`](/en-US/docs/Web/CSS/::after) don't work on `<select>` elements (this is because generated content is placed relative to an element's formatting box, but form inputs work more like replaced elements — their display is generated by the browser and put in place — and therefore don't have one):
```html
<label for="select">Select a fruit</label>
<div class="select-wrapper">
<select id="select" name="select">
<option>Banana</option>
<option>Cherry</option>
<option>Lemon</option>
</select>
</div>
```
We then use generated content to generate a little down arrow, and put it in the right place using positioning:
```css
.select-wrapper {
position: relative;
}
.select-wrapper::after {
content: "▼";
font-size: 1rem;
top: 6px;
right: 10px;
position: absolute;
}
```
The second, slightly more important issue is that you don't have control over the box that appears containing the options when you click on the `<select>` box to open it. You can inherit the font set on the parent, but you won't be able to set things like spacing and colors. The same is true for the autocomplete list that appears with {{HTMLElement("datalist")}}.
If you really need full control over the option styling, you'll have to either use some kind of library to generate a custom control, or build your own custom control, or in the case of select use the `multiple` attribute, which makes all the options appear on the page, sidestepping this particular problem:
```html
<label for="select">Select fruits</label>
<select id="select" name="select" multiple>
…
</select>
```
Of course, this might also not fit in with the design you are going for, but it's worth noting!
### Date input types
The date/time input types ([`datetime-local`](/en-US/docs/Web/HTML/Element/input/datetime-local), [`time`](/en-US/docs/Web/HTML/Element/input/time), [`week`](/en-US/docs/Web/HTML/Element/input/week), [`month`](/en-US/docs/Web/HTML/Element/input/month)) all have the same major associated issue. The actual containing box is as easy to style as any text input, and what we've got in this demo looks fine.
However, the internal parts of the control (e.g. the popup calendar that you use to pick a date, the spinner that you can use to increment/decrement values) are not stylable at all, and you can't get rid of them using `appearance: none;`. If you really need full control over the styling, you'll have to either use some kind of library to generate a custom control, or build your own.
> **Note:** It is worth mentioning [`<input type="number">`](/en-US/docs/Web/HTML/Element/input/number) here too — this also has a spinner that you can use to increment/decrement values, so potentially suffers from the same problem. However, in the case of the `number` type the data being collected is simpler, and it is easy to just use a `tel` input type instead which has the appearance of `text`, but displays the numeric keypad in devices with touch keyboards.
### Range input types
[`<input type="range">`](/en-US/docs/Web/HTML/Element/input/range) is annoying to style. You can use something like the following to remove the default slider track completely and replace it with a custom style (a thin red track, in this case):
```css
input[type="range"] {
appearance: none;
background: red;
height: 2px;
padding: 0;
outline: 1px solid transparent;
}
```
However, it is very difficult to customize the style of the range control's drag handle — to get full control over range styling you'll need to use a whole bunch of complex CSS code, including multiple non-standard, browser-specific pseudo-elements. Check out [Styling Cross-Browser Compatible Range Inputs with CSS](https://css-tricks.com/styling-cross-browser-compatible-range-inputs-css/) on CSS tricks for a detailed write-up of what's needed.
### Color input types
Input controls of type color are not too bad. In supporting browsers, they tend to just give you a block of solid color with a small border.
You can remove the border, just leaving the block of color, using something like this:
```css
input[type="color"] {
border: 0;
padding: 0;
}
```
However, a custom solution is the only way to get anything significantly different.
### File input types
Inputs of type file are generally OK — as you saw in our example, it is fairly easy to create something that fits in OK with the rest of the page — the output line that is part of the control will inherit the parent font if you tell the input to do so, and you can style the custom list of file names and sizes in any way you want; we created it after all.
The only problem with file pickers is that the button provided that you press to open the file picker is completely unstylable — it can't be sized or colored, and it won't even accept a different font.
One way around this is to take advantage of the fact that if you have a label associated with a form control, clicking the label will activate the control. So you could hide the actual form input using something like this:
```css
input[type="file"] {
height: 0;
padding: 0;
opacity: 0;
}
```
And then style the label to act like a button, which when pressed will open the file picker as expected:
```css
label[for="file"] {
box-shadow: 1px 1px 3px #ccc;
background: linear-gradient(to bottom, #eee, #ccc);
border: 1px solid rgb(169, 169, 169);
border-radius: 5px;
text-align: center;
line-height: 1.5;
}
label[for="file"]:hover {
background: linear-gradient(to bottom, #fff, #ddd);
}
label[for="file"]:active {
box-shadow: inset 1px 1px 3px #ccc;
}
```
You can see the result of the above CSS styling in the below live example (see also [styled-file-picker.html](https://mdn.github.io/learning-area/html/forms/styling-examples/styled-file-picker.html) live, and the [source code](https://github.com/mdn/learning-area/blob/main/html/forms/styling-examples/styled-file-picker.html)).
{{EmbedGHLiveSample("learning-area/html/forms/styling-examples/styled-file-picker.html", '100%', 200)}}
### Meters and progress bars
[`<meter>`](/en-US/docs/Web/HTML/Element/meter) and [`<progress>`](/en-US/docs/Web/HTML/Element/progress) are possibly the worst of the lot. As you saw in the earlier example, we can set them to the desired width relatively accurately. But beyond that, they are really difficult to style in any way. They don't handle height settings consistently between each other and between browsers, you can color the background, but not the foreground bar, and setting `appearance: none` on them makes things worse, not better.
It is easier to just create your own custom solution for these features, if you want to be able to control the styling, or use a third-party solution such as [progressbar.js](https://kimmobrunfeldt.github.io/progressbar.js/#examples).
The article [How to build custom form controls](/en-US/docs/Learn/Forms/How_to_build_custom_form_controls) provides an example of how to build a custom designed select with HTML, CSS, and JavaScript.
## Summary
While there are still difficulties using CSS with HTML forms, there are ways to get around many of the problems. There are no clean, universal solutions, but modern browsers offer new possibilities. For now, the best solution is to learn more about the way the different browsers support CSS when applied to HTML form controls.
In the next article of this module, we will explore the different [UI pseudo-classes](/en-US/docs/Learn/Forms/UI_pseudo-classes) available to us in modern browsers for styling forms in different states.
{{PreviousMenuNext("Learn/Forms/Styling_web_forms", "Learn/Forms/UI_pseudo-classes", "Learn/Forms")}}
### Advanced Topics
- [How to build custom form controls](/en-US/docs/Learn/Forms/How_to_build_custom_form_controls)
- [Sending forms through JavaScript](/en-US/docs/Learn/Forms/Sending_forms_through_JavaScript)
- [Property compatibility table for form widgets](/en-US/docs/Learn/Forms/Property_compatibility_table_for_form_controls)