The element is removed from the normal document flow and is positioned relative to the nearest positioned ancestor (an ancestor with position set to relative, absolute, fixed, or sticky). If no positioned ancestor is found, it will be positioned relative to the initial containing block (usually the <html> element).
Position properties (top, right, bottom, left) specify the distance between the element and its positioned ancestor.
Use it, when you want to place an element at a specific position on the page, such as for dropdown menus, tooltips, or modal popups.
Key Characteristics
1. When an element is positioned absolutely, it does not take up space in the normal flow of the document. Surrounding elements behave as if the absolutely positioned element does not exist.
2. Use of top, right, bottom, and left Properties
These properties define the position offsets from the containing block's edges.The values can be positive or negative, affecting the direction of movement:
· top: 20px moves the element 20 pixels down from the top of the containing block.
· right: 30px moves the element 30 pixels to the left from the right edge.
· bottom: 15px moves the element 15 pixels up from the bottom edge.
· left: 10px moves the element 10 pixels to the right from the left edge.
3. Stacking Context and Z-Index
position: absolute allows you to use the z-index property to control stacking order. Elements with higher z-index values appear on top of elements with lower values.
Following example will help you understand how the absolute positioning relates to the grandparent when the parent container doesn't have a position set.
absolute-position.html
<!DOCTYPE html> <html> <head> <title>Position Absolute Example</title> <style> .grandParent { display: flex; flex-wrap: wrap; padding: 20px; margin: 20px; width: 90vw; height: 60vh; background-color: lightgrey; position: relative; /* Establishes a positioning context */ } .parent { background: #dc9096; width: 200px; height: 150px; color: white; font-size: 1.2em; margin: 30px; padding-top: 20px; /* Prevents margin collapse */ position: static; /* Default position, no positioning context set here */ } .parent .child { height: 30px; margin-top: 10px; display: flex; align-items: center; justify-content: center; background-color: #ccc; color: black; } .child1 { background: #f0d43a; } .child2 { background: #22b2da; } .child3 { background: #3b4a6b; color: white; } /* Absolute positioning of child1 within different parents */ .parent1 .child1 { position: absolute; top: 50px; /* Moves 50px down from the top of the grandParent */ left: 20px; /* Moves 20px right from the left of the grandParent */ background: #f89f29; } .parent2 .child1 { position: absolute; bottom: 30px; /* Moves 30px up from the bottom of the grandParent */ right: 40px; /* Moves 40px left from the right of the grandParent */ background: #8bc34a; } /* Styles for better visibility */ h1 { width: 100%; text-align: center; margin-bottom: 20px; } </style> </head> <body> <div class="grandParent"> <h1>Grand Parent Container</h1> <div class="parent"> <div class="child1 child">Child 1 (No Position)</div> <div class="child2 child">Child 2</div> <div class="child3 child">Child 3</div> </div> <div class="parent parent1"> <div class="child1 child">{top: 50px; left: 20px}</div> <div class="child2 child">Child 2</div> <div class="child3 child">Child 3</div> </div> <div class="parent parent2"> <div class="child1 child">{bottom: 30px; right: 40px}</div> <div class="child2 child">Child 2</div> <div class="child3 child">Child 3</div> </div> </div> </body> </html>
Above snippet generate below screen.
Grand Parent Container (.grandParent)
The .grandParent has position: relative, which establishes it as the nearest positioned ancestor. This means any absolutely positioned child elements will use the .grandParent as their reference for positioning.
Parent Containers (.parent, .parent1, .parent2)
These containers do not have a position set (default static), meaning they do not establish a new positioning context. Therefore, the absolute positioning of .child1 elements will still be relative to the .grandParent.
Positioning the .child1 Elements:
· In .parent1, the .child1 is set with position: absolute; top: 50px; left: 20px;, moving it 50 pixels down from the top and 20 pixels right from the left of the .grandParent.
· In .parent2, the .child1 is set with position: absolute; bottom: 30px; right: 40px;, moving it 30 pixels up from the bottom and 40 pixels left from the right of the .grandParent.
Visual Indicators
The different background colors and positions of the .child1 elements help visualize how the absolute positioning is based on the .grandParent's boundaries, not the .parent containers.
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