Why Doesn't My Sticky Element with `bottom: 0` Appear to Stick?
Dec 20, 2024 am 10:53 AMUnderstanding CSS Sticky Positioning and Its Behavior with top and bottom
CSS's sticky positioning allows an element to remain fixed within its containing block until a specific threshold is crossed, where it then becomes relatively positioned. However, there appears to be a discrepancy when using 'bottom: 0' with sticky elements.
Problem Explanation:
Consider the following code:
<div class="block"> <div class="move"> </div> </div>
.block { background: pink; width: 50%; height: 200px; } .move { position: sticky; bottom: 0; }
When 'move' is set to 'top:0', it sticks to the top of the pink block, behaving as expected. However, when 'move' is set to 'bottom:0', it appears to become detached and no longer remains fixed.
Understanding the behavior of 'bottom: 0' with sticky elements:
To understand this behavior, it's crucial to grasp the definition of sticky positioning:
A stickily positioned element remains relatively positioned until its containing block crosses a specified threshold (such as setting 'top' to a value other than 'auto'), after which it becomes 'stuck' until meeting the opposite edge of its containing block.
In the case of 'bottom: 0', the sticky element is not visible because it is stuck to the bottom edge of its containing block. As the scroll position passes the threshold, the containing block moves up, but the sticky element remains fixed to the bottom edge. Since the sticky element is already at the bottom, it cannot move any further upwards.
To observe the sticky behavior, ensure the containing block has sufficient height to accommodate the sticky element. By providing a significant top margin to the block element, you can scroll through the page and see the sticky element adhere to the bottom
The above is the detailed content of Why Doesn't My Sticky Element with `bottom: 0` Appear to Stick?. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

CSS blocks page rendering because browsers view inline and external CSS as key resources by default, especially with imported stylesheets, header large amounts of inline CSS, and unoptimized media query styles. 1. Extract critical CSS and embed it into HTML; 2. Delay loading non-critical CSS through JavaScript; 3. Use media attributes to optimize loading such as print styles; 4. Compress and merge CSS to reduce requests. It is recommended to use tools to extract key CSS, combine rel="preload" asynchronous loading, and use media delayed loading reasonably to avoid excessive splitting and complex script control.

ThebestapproachforCSSdependsontheproject'sspecificneeds.Forlargerprojects,externalCSSisbetterduetomaintainabilityandreusability;forsmallerprojectsorsingle-pageapplications,internalCSSmightbemoresuitable.It'scrucialtobalanceprojectsize,performanceneed

No,CSSdoesnothavetobeinlowercase.However,usinglowercaseisrecommendedfor:1)Consistencyandreadability,2)Avoidingerrorsinrelatedtechnologies,3)Potentialperformancebenefits,and4)Improvedcollaborationwithinteams.

CSSismostlycase-insensitive,butURLsandfontfamilynamesarecase-sensitive.1)Propertiesandvalueslikecolor:red;arenotcase-sensitive.2)URLsmustmatchtheserver'scase,e.g.,/images/Logo.png.3)Fontfamilynameslike'OpenSans'mustbeexact.

Autoprefixer is a tool that automatically adds vendor prefixes to CSS attributes based on the target browser scope. 1. It solves the problem of manually maintaining prefixes with errors; 2. Work through the PostCSS plug-in form, parse CSS, analyze attributes that need to be prefixed, and generate code according to configuration; 3. The usage steps include installing plug-ins, setting browserslist, and enabling them in the build process; 4. Notes include not manually adding prefixes, keeping configuration updates, prefixes not all attributes, and it is recommended to use them with the preprocessor.

CSScounterscanautomaticallynumbersectionsandlists.1)Usecounter-resettoinitialize,counter-incrementtoincrease,andcounter()orcounters()todisplayvalues.2)CombinewithJavaScriptfordynamiccontenttoensureaccurateupdates.

In CSS, selector and attribute names are case-sensitive, while values, named colors, URLs, and custom attributes are case-sensitive. 1. The selector and attribute names are case-insensitive, such as background-color and background-Color are the same. 2. The hexadecimal color in the value is case-sensitive, but the named color is case-sensitive, such as red and Red is invalid. 3. URLs are case sensitive and may cause file loading problems. 4. Custom properties (variables) are case sensitive, and you need to pay attention to the consistency of case when using them.

CSSselectorsandpropertynamesarecase-insensitive,whilevaluescanbecase-sensitivedependingoncontext.1)Selectorslike'div'and'DIV'areequivalent.2)Propertiessuchas'background-color'and'BACKGROUND-COLOR'aretreatedthesame.3)Valueslikecolornamesarecase-insens
