Watch how it simply overlaps the existing content instead of pushing it around. Make the following highlighted changes to the two rules: Specifying dimensions Absolutely positioned elements will shrink-wrap to fit their contents unless you specify their dimensions. This stuff is tricky, but it's essential to creating great CSS layouts. If a positioned ancestor doesn't exist, the initial container is used. A stickily positioned element is treated as relatively positioned until it crosses a specified threshold, at which point it is treated as fixed.
Absolute vs. Relative - Explaining CSS Positioning
The region, a by pixel square, displays only a portion of the image; the rest is clipped from view. Rather than sliding offscreen with the rest of the content, the "B" heading will then remain fixed to the top of the viewport until all the "B" items have scrolled offscreen, at which point it will be covered up by the "C" heading, and so on. At the bottom of the stack is an envelope with stack level 1, containing two inner envelopes the blue square and the cyan square. You'll have to remove the automatic horizontal margins on the body element to make this possible. Sticky position offsets may cause them to overlap. Copy This example places the img element at the upper-left corner of the div element, which is itself positioned on the page.
CSS absolute and fixed positioning - W3C Wiki
Auto heights for block formatting context roots 2 3 9. Similar to the containing boxes of absolute positioning, fixed position elements are independent. It would remain in the normal flow of the document, and just be offset slightly. Relative positioning depends on the default flow of the document, and reflows content should the user resize the browser.
Description: The parent and its descendants will form an indivisible unit within the stacking context that surrounds the parent. Add the following highlighted lines to your CSS rules: Since boxes are not split or stretched as a result of left or right , the used values are always: CSS absolute and fixed positioning , written by Tommy Olsson. Controlling an elements position can make use of a variety of layout techniques.