Positioning of elements. Absolute positioning in CSS. Absolutely positioned elements ignore the float property
They work with all positioned elements except static ones.
Positioning example.
Elements can overlap each other!
Displaying an element above the rest!
The position property has 4 values: static, fixed, relative and absolute. Each of these meanings will be demonstrated below with an example of use.
Before we examine in detail all types of positioning of elements on a page, we will have to consider what document flow is.
Document flow
By default, elements on a web page are displayed in the order in which they appear in the HTML document, that is, block elements occupy the full width available to them and are stacked vertically one below the other. Inline elements are lined up horizontally until the entire available width is occupied, after the entire width is occupied, a line break is made and everything starts again. This arrangement of elements is called normal flow(also called document flow or general flow).
You can use the float or position property to remove an element from the normal flow. If an element "falls out" of the normal flow, then elements that are located in the code below that element will be shifted into its place on the web page.
Static positioning
Static is the default positioning for all elements on a web page. If not applied to the element position property, then it will be static and will be displayed on the web page according to the general flow of elements.
At using CSS properties top , left , right or bottom to a statically positioned element, they will be ignored.
If necessary, you can set static positioning in the style sheet using the static value:
First paragraph.
Second paragraph.
Try »Fixed positioning
Elements with fixed positioning are located on the page relative to the browser window. Such elements are removed from the overall flow; elements following the fixed element in the flow will ignore it, moving and taking its place on the web page.
It is worth paying attention to the fact that elements with fixed positioning can overlap other elements, hiding them completely or partially. While scrolling long pages, they create the effect of motionless objects, remaining in the same place:
Text Text Text Text Text Text Text Some text Text Text Text Text TextTry »
Relative Positioning
Relatively positioned elements, like static elements, remain in the general flow. When applying top , left , right or bottom properties to relatively positioned elements, they will move relative to their position, leaving empty space where the element was originally located.
Such elements do not affect the position of the elements surrounding them; the remaining elements remain in place and can be overlapped by a relatively positioned element:
First level title.
Relatively positioned title.
Third level heading.
Try »Note: Elements with relative positioning (relative) are usually used as a parent for elements with absolute positioning (absolute).
Absolute positioning
Absolutely positioned elements are completely removed from the overall flow, the remaining elements will take up the free space, completely ignoring absolutely positioned elements. You can then position the element wherever you want on the web page using the top , left , right , or bottom properties.
All absolutely positioned elements are placed relative to the browser window or relative to the nearest positioned ancestor (if there is one) that has a position property of absolute , fixed , or relative .
Let's change the location of the logo using absolute positioning.
Now the logo will be located on the right top corner pages.
Overlapping elements
When elements are outside the overall flow of the page, they can overlap each other. Typically, the order of elements corresponds to their order in the HTML code of the page, however, it is possible to control the order of overlap using the CSS property z-index , the higher its value, the higher the element will be.
15.03.2017
Not yet
Hi all!
In today's tutorial I'll show you how you can use block positioning to place an element anywhere on the screen.
What does block positioning give us? With the help of block positioning, a webmaster will be able to create any unique website design, placing blocks where he wants. To place blocks anywhere on the screen, just specify the coordinates.
Coordinates in CSS
Property "TOP» | «
LEFT» | «
RIGHT» | «
BOTTOM
»
Coordinates must be specified for the positioning of blocks, that is, where the block will be placed.
Coordinate system diagram:
Coordinates are specified by four rules:
- top- up;
- left- left;
- right- right;
- bottom- down.
Syntax:
Rule_Coordinate: value_coordinate;
Meaning:
Specify the value in px or %.
Top:100px; /* top edge */ left:100px; /* left edge */
It is enough just to specify the coordinates for two edges (top or bottom, left or right).
Positioning in CSS
Property "POSITION
»
Positioning is written in CSS through the “position” rule with the desired value.
Syntax:
Position: value;
Meaning:
- absolute– absolute;
- relative– relative;
- fixed– fixed.
Let's go through each value.
Meaning "
ABSOLUTE"
Absolute positioning allows the webmaster to place blocks on a web page anywhere on the screen. It is enough to write the “position” rule in CSS with the value “absolute” and the required coordinates:
Position:absolute; /* absolute positioning*/
Result:
Meaning "RELATIVE
»
Relative Positioning allows a webmaster to move a block on a web page, but the block's original space is not freed up for another element. In CSS, write the “position” rule with the value “relative” and the desired coordinates:
Position:relative; /* relative positioning*/
CSS stands for Cascading Style Sheets. CSS describes how HTML elements are to be displayed on screen, paper, or in other media. CSS saves a lot of work. It can control the layout of multiple web pages all at once. CSS can be added to HTML elements in 3 ways: Inline - by using the style attribute in HTML elements Internal - by using a element in the section External - by using an external CSS file The most common way to add CSS, is to keep the styles in separate CSS files. However, here we will use inline and internal styling, because this is easier to demonstrate, and easier for you to try it yourself.
Result:
Default
Relative Positioning
Fixed positioning in CSS
"FIXED" value
Fixed positioning allows the webmaster to place blocks on a web page anywhere on the screen, and when scrolling the web page, the block will always be located relative to the browser window (will always be visible on the screen). It is enough to write the “position” rule in CSS with the value “fixed” and the required coordinates:
Position:fixed; /* fixed positioning */
CSS stands for Cascading Style Sheets. CSS describes how HTML elements are to be displayed on screen, paper, or in other media. CSS saves a lot of work. It can control the layout of multiple web pages all at once. CSS can be added to HTML elements in 3 ways: Inline - by using the style attribute in HTML elements Internal - by using a element in the section External - by using an external CSS file The most common way to add CSS, is to keep the styles in separate CSS files. However, here we will use inline and internal styling, because this is easier to demonstrate, and easier for you to try it yourself.
If the result is not visible or clear, add enough text to create a scroll bar on the web page screen.
That's it for the lesson! There are still 2-3 lessons left and you will finish mastering CSS basics. This means you can create beautiful websites with ease.
Don't miss the rest of the lessons! Subscribe to updates!
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When working with text, the user may need to swap sentences or entire paragraphs or arrange fragments in some non-standard way. Move a block of text in an application Microsoft Office Word can be done in several ways.
Instructions
Ctrl, Shift and right/left arrow highlight a word, and if you use the up or down arrows, you can select an entire paragraph.
A block element in HTML is an element that, by default, occupies the entire width of its parent element. The parent element can be another block element, or a browser window. You can set the width and height of a block element using CSS properties. Positioning block elements called the process of their location inside the browser window and relative friend with using CSS properties position , left , top , right and bottom . Property CSS position is intended to set one of four available types of positioning: static (default), absolute, fixed and relative. Rest CSS properties, namely left , top , right and bottom are intended to specify distances relative to the left, top, right and bottom edges of the parent element. Also, block elements can overlap each other when setting certain properties, and this opportunity the same can be used on websites.
Default positioning (static)
If you did not specify a position for a block element or specified static , which is the same thing, then the block elements are arranged in order. Moreover, the next block (for example: red) is located with new line. Also, this positioning is not affected by setting the distances left , top , right and bottom .
Absolute positioning (absolute)
With absolute positioning, the position of an element is specified relative to the edges of the browser window using distances specified by the left , top , right , and bottom properties. If you specify the distances left and right at the same time, and they conflict with each other, then preference is given to left , the same goes for top and bottom , in which the distance top takes precedence. Absolute positioning is very often used in conjunction with relative positioning for design purposes, when it is necessary to place various elements relative to each other; it can also be used to create drop-down menus, site layout, etc.
Fixed positioning
Fixed positioning is different from other types of positioning and does not move with the content as you scroll the page. Fixed-position block elements are anchored using the left , top , right , and bottom properties to the edges of the browser window. Fixed positioning is used to create frame interfaces (the browser window is divided into several areas), fixed menus, fixed basement site and “permanent” blocks (list of links, social buttons etc.).
Relative positioning
Relative positioning is specified by specifying the distances left , top , right , and bottom relative to its current position.
However, this block position can also be created using margin properties(indents).
Relative positioning isn't fun to use on its own, it's mostly used in conjunction with absolute positioning.
Let's consider the options:
Two main tools are often used for page layout - positioning And free movement (floating). CSS positioning lets you specify where an element's box appears, and free float moves elements to the left or right edge of the container box, allowing the rest of the content to "flow" around it.
Positioning and free movement of elements
1. Types of positioning
The position property allows you to specify the new location of the block relative to where it would be in the normal flow of the document. By default, all elements are arranged sequentially one after another in the order in which they are defined in the structure of the HTML document. The property is not inherited.
| position | |
|---|---|
| Meaning: | |
| static | The default value means no positioning. Elements are displayed sequentially one after another in the order in which they are defined in the HTML document. Used to clear any other positioning value. |
| relative | A relatively positioned element is moved from its normal location in different directions relative to the boundaries parent container, and the space it occupied does not disappear. However, such an element may overlap other content on the page. If for a relatively positioned element you set the properties top and bottom or left and right at the same time, then in the first case only top will work, in the second - left. Relative positioning allows you to set a z-index for an element, as well as absolute positioning child elements inside the block. |
| absolute | An absolutely positioned element is completely removed from the document flow and positioned relative to the boundaries of its container block (another element or browser window). The container block for an absolutely positioned element is the closest ancestor element whose position property value is not static . The location of the element's edges is determined using the offset properties. The space that such an element occupied collapses as if the element did not exist on the page. An absolutely positioned element can overlap or be superseded by other elements (due to z-index properties). Any absolutely positioned element generates a block, that is, it takes on the value display: block; . |
| fixed | Fixes an element at a specified location on the page. The container block of a fixed element is the viewport, that is, the element is always fixed relative to the browser window and does not change its position while scrolling the page. The element itself is completely removed from the main document flow and created in a new document flow. |
| initial | Sets the property value to the default value. |
| inherit | Inherits the property value from the parent element. |
Rice. 1. Difference between static, relative and absolute positioning 2. Offset properties
Properties describe the offset relative to the nearest side of the container block. Set for elements for which the position property value is not static . They can take both positive and negative values. Not inherited.
For the top property, positive values move the top edge of the positioned element below, and negative values move the top edge of its container block. For the left property, positive values move the edge of the positioned element to the right, and negative values move the edge of the positioned element to the left. That is, positive values move the element inside the container block, and negative values move it outside it.
3. Positioning within an element
For the container block of an absolutely positioned element, the position: relative property is set without offsets. This allows elements to be positioned within a container element.
Rice. 2. Absolute relative positioning4. Positioning problems
1. If the width or height of an absolutely positioned element is set to auto , then its value will be determined by the width or height of the element's content. If the width or height is declared explicitly, then this is the value that will be assigned.
2. If inside a block with position: absolute there are elements for which the float is set, then the height of this element will be equal to the height of the tallest of these elements.
3. An element with position: absolute or position: fixed cannot be set at the same time float property, but for an element with position: relative - it’s possible.
4. If the ancestor of the positioned element is a block element, then the block container is formed by the content area limited by the border. If the ancestor is an inline element, the container block is formed by the outer boundary of its contents. If there is no ancestor, the container block is the body element.
5. Free movement of elements
In the normal order, block elements are rendered starting from the top edge of the browser window and working towards the bottom edge. The float property allows you to move any element, aligning it to the left or right edge of the web page or the container element that contains it. In this case, other block elements will ignore it, and inline elements will shift to the right or left, freeing up space for it and flowing around it.
Rice. 3. Free movement of elements A floating block takes on the dimensions of its contents, taking into account padding and borders. The top and bottom margins of floating elements do not collapse. The float property applies to both block elements and inline elements.
The left or right outer edge of a moved element, unlike positioned elements, cannot be located to the left (or right) of the inner edge of its container block, i.e. go beyond its boundaries. Moreover, if the container block is set to padding, then the floating block will be spaced from the edge of the container block at a specified distance.
The property automatically changes the calculated (displayed in the browser) value display properties to display: block for the following values: inline , inline-block , table-row , table-row-group , table-column , table-column-group , table-cell , table-caption , table-header-group , table- footer-group . The value of inline-table changes to table .
The property has no effect on elements with display: flex and display: inline-flex .
When using the float property on block elements, be sure to specify a width. This will allow the browser to create space for other content. But if the combined width of all columns is greater than the available space, then the last element will go down.
At the same time, the vertical margins streamlined elements do not collapse with the padding of adjacent elements, unlike regular block elements.
6. Cancel flow around elements
6.1. clear property
The clear property determines how the element that follows the floating element will be positioned. The property cancels the float on one or both sides of the element that is set by the float property. To prevent background or borders from being displayed under floating elements, use the (overflow: hidden;) rule.
6.2. Cleaning a stream with styles using the clearfix class and the :after pseudo-class
Suppose you have a block container for which the width and height are not specified. A floating block with specified dimensions is placed inside it.
Rice. 4. “Collapse effect” of the container blockSolution to the problem:
We create the .clearfix class and, in combination with the :after pseudo-class, apply it to the container block.
Second option for clearing the stream:
Clearfix:after ( content: ""; display: table; clear: both; ) 
Rice. 5. Applying the “cleaning” method to a container block containing a floating element
6.3. An easy way to clean a stream
There is another trick to clean up the flow for an element containing floating elements, such as a horizontal bulleted list:
Ul ( margin: 0; list-style: none; padding: 20px; background: #e7e6d4; overflow: auto; ) li ( float: left; width: calc(100% / 3 - 20px); height: 50px; margin- right: 20px; background: #ffffff; border: 3px dashed #666666; ) li:last-child (margin-right: 0;) Fig. 6. Cleaning up the horizontal list flow
