There are multiple ways to hide an element in CSS, but they differ in the way they affect accessibility, layout, animation, performance, and event handling.

Animation

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

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.

See the Pen
hide with opacity: 0 by SitePoint (@SitePoint)
on CodePen.

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:

See the Pen
hide with color alpha by SitePoint (@SitePoint)
on CodePen.

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

metric	effect
browser support	good, but IE only supports transparent and rgba
accessibility	content still read
layout affected?	no
rendering required	painting
performance	good, but not as fast as opacity
animation frames possible?	yes
events triggered when hidden?	yes

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:

See the Pen
hide with transform: scale(0); by SitePoint (@SitePoint)
on CodePen.

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.

See the Pen
hide with clip-path by SitePoint (@SitePoint)
on CodePen.

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:

See the Pen
hide with visibility: hidden by SitePoint (@SitePoint)
on CodePen.

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.

See the Pen
hide with display: none by SitePoint (@SitePoint)
on CodePen.

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:

[hidden] { display: none;
}

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:

See the Pen
hide with position: absolute by SitePoint (@SitePoint)
on CodePen.

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:

See the Pen
hide with an overlay by SitePoint (@SitePoint)
on CodePen.

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.

See the Pen
hide with width or height by SitePoint (@SitePoint)
on CodePen.

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.

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Source: https://www.sitepoint.com/hide-elements-in-css/?utm_source=rss