Html css style hide

10 Ways to Hide Elements in CSS

Some CSS hiding options are all or nothing. The element is either fully visible or fully invisible and there’s no in-between state. Others, such as transparency, can have a range of values, so interpolated CSS animations become possible.

Accessibility

Each method described below will visually hide an element, but it may or may not hide the content from assistive technologies. For example, a screen reader could still announce tiny transparent text. Further CSS properties or ARIA attributes such as aria-hidden=»true» may be necessary to describe the appropriate action.

Be wary that animations can also cause disorientation, migraines, seizures, or other physical discomfort for some people. Consider using a prefers-reduced-motion media query to switch off animations when specified in user preferences.

Event Handling

Hiding will either stop events being triggered on that element or have no effect — that is, the element is not visible but can still be clicked or receive other user interactions.

Performance

After a browser loads and parses the HTML DOM and CSS object model, the page is rendered in three stages:

  1. Layout: generate the geometry and position of each element
  2. Paint: draw out the pixels for each element
  3. Composition: position element layers in the appropriate order
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An effect which only causes composition changes is noticeably smoother than those affecting layout. In some cases, the browser can also use hardware acceleration.

1. opacity and filter: opacity()

The opacity: N and filter: opacity(N) properties can be passed a number between 0 and 1, or a percentage between 0% and 100% denoting fully transparent and fully opaque accordingly.

There’s little practical difference between the two in modern browsers, although filter should be used if multiple effects are applied at the same time (blur, contrast, grayscale etc.)

Opacity can be animated and offers great performance, but be wary that a fully transparent element remains on the page and can trigger events.

metric effect
browser support good, but IE only supports opacity 0 to 1
accessibility content not read if 0 or 0% is set
layout affected? no
rendering required composition
performance best, can use hardware acceleration
animation frames possible? yes
events triggered when hidden? yes

2. color Alpha Transparency

opacity affects the whole element, but it’s also possible to set the color , background-color , and border-color properties separately. Applying a zero alpha channel using rgba(0,0,0,0) or similar renders an item fully transparent:

Each property can be animated separately to create interesting effects. Note that transparency can’t be applied to elements with image backgrounds unless they’re generated using linear-gradient or similar.

The alpha channel can be set with:

  • transparent : fully transparent (in-between animations are not possible)
  • rgba(r, g, b, a) : red, green, blue, and alpha
  • hsla(h, s, l, a) : hue, saturation, lightness, and alpha
  • #RRGGBBAA and #RGBA

3. transform

The transform property can be used to translate (move), scale, rotate, or skew an element. A scale(0) or translate(-999px, 0px) off-screen will hide the element:

transform offers excellent performance and hardware acceleration because the element is effectively moved into a separate layer and can be animated in 2D or 3D. The original layout space remains as is, but no events will be triggered by a fully hidden element.

metric effect
browser support good
accessibility content still read
layout affected? no — the original dimensions remain
rendering required composition
performance best, can use hardware acceleration
animation frames possible? yes
events triggered when hidden? no

4. clip-path

The clip-path property creates a clipping region that determines which parts of an element are visible. Using a value such as clip-path: circle(0); will completely hide the element.

clip-path offers scope for interesting animations, although it should only be relied on in modern browsers.

metric effect
browser support modern browsers only
accessibility content still read by some applications
layout affected? no — the original dimensions remain
rendering required paint
performance reasonable
animation frames possible? yes, in modern browsers
events triggered when hidden? no

5. visibility

The visibility property can be set to visible or hidden to show and hide an element:

The space used by the element remains in place unless a collapse value is used.

metric effect
browser support excellent
accessibility content not read
layout affected? no, unless collapse is used
rendering required composition, unless collapse is used
performance good
animation frames possible? no
events triggered when hidden? no

6. display

display is probably the most-used element-hiding method. A value of none effectively removes the element as if it never existed in the DOM.

However, it’s possibly the worst CSS property to use in the majority of cases. It can’t be animated and will trigger a page layout unless the element is moved out of the document flow using position: absolute or the new contain property is adopted.

display is also overloaded, with options such as block , inline , table , flexbox , grid and more. Resetting back to the correct value after display: none; can be problematic (although unset may help).

metric effect
browser support excellent
accessibility content not read
layout affected? yes
rendering required layout
performance poor
animation frames possible? no
events triggered when hidden? no

7. HTML hidden attribute

The HTML hidden attribute can be added to any element:

p hidden> Hidden content p> 

to apply the browser’s default style:

This has the same benefits and flaws as display: none , although it could be useful when using a content management system that doesn’t permit style changes.

8. Absolute position

The position property allows an element to be moved from its default static position within the page layout using top , bottom , left , and right . An absolute -positioned element can therefore be moved off-screen with left: -999px or similar:

metric effect
browser support excellent, unless using position: sticky
accessibility content still read
layout affected? yes, if positioning is changed
rendering required depends
performance reasonable if careful
animation frames possible? yes, on top , bottom , left , and right
events triggered when hidden? yes, but it may be impossible to interact with an off-screen element

9. Overlay Another Element

An element can be visually hidden by positioning another over the top which has the same color as the background. In this example, an ::after pseudo-element is overlaid, although any child element could be used:

While technically possible, this option required more code than other options.

metric effect
browser support excellent
accessibility content still read
layout affected? no, if absolutely positioned
rendering required paint
performance reasonable if careful
animation frames possible? yes
events triggered when hidden? yes, when a pseudo or child element is overlaid

10. Reduce Dimensions

An element can be hidden by minimizing its dimensions using width , height , padding , border-width and/or font-size . It may also be necessary to apply overflow: hidden; to ensure content doesn’t spill out.

Interesting animated effects are possible, but performance is noticeably better with transform .

metric effect
browser support excellent
accessibility content still read
layout affected? yes
rendering required layout
performance poor
animation frames possible? yes
events triggered when hidden? no

Hidden Choices

display: none has been the favorite solution to hide elements for many years, but it’s been superseded by more flexible, animatable options. It’s still valid, but perhaps only when you want to permanently hide content from all users. transform or opacity are better choices when considering performance.

Take your CSS skills to the next level with CSS Master. Learn CSS architecture, debugging, custom properties, advanced layout and animation techniques, how to use CSS with SVG, and more.

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Craig is a freelance UK web consultant who built his first page for IE2.0 in 1995. Since that time he’s been advocating standards, accessibility, and best-practice HTML5 techniques. He’s created enterprise specifications, websites and online applications for companies and organisations including the UK Parliament, the European Parliament, the Department of Energy & Climate Change, Microsoft, and more. He’s written more than 1,000 articles for SitePoint and you can find him @craigbuckler.

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visibility

Чтобы скрыть и удалить элемент из разметки, установите свойству display значение none , вместо использования visibility .

Синтаксис

/* Значения */ visibility: visible; visibility: hidden; visibility: collapse; /* Глобальные значения */ visibility: inherit; visibility: initial; visibility: unset; 

Свойство visibility указывается в качестве одного из значений ниже.

Значения

Значение по умолчанию, элемент виден.

Элемент не виден (полностью прозрачный, ничего не отображается), но продолжает влиять на шаблон. Потомки элемента могут быть показаны с помощью свойства visibility:visible . Элемент не может получить focus (например, при навигации с помощью tabindex).

* Для строк, столбцов, групп столбцов и групп строк в таблице, которые должны быть удалены (как с помощью display : none применённого к столбцу/строке таблицы). Однако, размер других строк и столбцов должен продолжать вычисляться так, словно скрытые строки/столбцы присутствуют. Это создано для быстрого удаления строк/столбцов из таблицы без дополнительного вычисления ширины и высоты частей таблицы.

  • Для XUL элементов размер всегда равен 0, независимо от других стилей, влияющих на размер, хотя отступы продолжают учитываться.
  • Для других элементов collapse обрабатывается также, как hidden

Синтаксис

Интерполяция

Значения видимости изменяются между видим и не видим. Интерполяция будет, если одно из начальных или конечных значений будет видимо или нет. Если одно из значений visible , интерполируется как дискретный шаг, где значения временной функции от 0 до 1 для visible и другие значения временной функции (которые происходят только в начале/конце перехода, или как результат функции cubic-bezier() со значениями вне [0, 1]) ближе к конечной точке.

Примеры

Базовый пример

HTML

p class="visible">Первый параграф виден.p> p class="not-visible">Второй параграф не виден.p> p class="visible">Третий параграф также виден. Заметь, второй параграф занимает место.p> 

CSS

.visible  visibility: visible; > .not-visible  visibility: hidden; > 

Пример с таблицей

HTML

table> tr> td>1.1td> td class="collapse">1.2td> td>1.3td> tr> tr class="collapse"> td>2.1td> td>2.2td> td>2.3td> tr> tr> td>3.1td> td>3.2td> td>3.3td> tr> table> 

CSS

.collapse  visibility: collapse; > table  border: 1px solid red; > td  border: 1px solid gray; > 

Соображения доступности

Использование visibility со значением hidden на элементе удалит его из дерева доступности. Это приведёт к тому, что элемент и все его дочерние элементы больше не будут показаны в скринридерах.

Примечания

  • Поддержка visibility:collapse отсутствует или частично не работает в некоторых современных браузерах. Во многих случаях может не корректно работать visibility:hidden со столбцами и строками.
  • visibility:collapse может изменить шаблон таблицы, если таблица содержит вложенные таблицы, пока visibility:visible не указан явно для вложенной таблицы.

Спецификация

Specification Status Comment
CSS Flexible Box Layout Module
Определение ‘visibility’ в этой спецификации.
Кандидат в рекомендации Определяет значение collapse применимым к flex элементам
CSS Box Model
Определение ‘visibility’ в этой спецификации.
Кандидат в рекомендации Без изменений
CSS Transitions
Определение ‘visibility’ в этой спецификации.
Рабочий черновик Определяет visibility как анимируемое.
CSS Level 2 (Revision 1)
Определение ‘visibility’ в этой спецификации.
Рекомендация Изначальное определение
Начальное значение visible
Применяется к все элементы
Наследуется да
Обработка значения как указано
Animation type видимость

Совместимость с браузерами

BCD tables only load in the browser

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This page was last modified on 13 авг. 2022 г. by MDN contributors.

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