In absolute positioning, what parameters can be used as a reference?-CSS Tutorial-php.cn

Home

Web Front-end

CSS Tutorial

In absolute positioning, what parameters can be used as a reference?

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jan 23, 2024 am 09:55 AM

absolute positioningReference parametersPositioning parameters

In absolute positioning, what parameters can be used as a reference?

Absolute positioning is a layout method commonly used in front-end development. It can accurately place elements at specified positions and follow the page scroll without position changes. When performing absolute positioning, we need to refer to some parameters to ensure that the element can be accurately positioned at the desired location. This article will introduce several commonly used parameters as a reference and give specific code examples.

1. Left, top, right, and bottom parameters

In absolute positioning, specify the left side of the element relative to its containing element by setting the left, top, right, and bottom parameters of the element. , upper, right and lower offsets. These parameters can be specific pixel values or percentage values.

Code example:

<!DOCTYPE html>
<html>
  <head>
    <style>
      .container {
        position: relative;
        width: 400px;
        height: 400px;
        background-color: lightgray;
      }
      .box {
        position: absolute;
        left: 50px;
        top: 50px;
        width: 200px;
        height: 200px;
        background-color: red;
      }
    </style>
  </head>
  <body>
    <div class="container">
      <div class="box"></div>
    </div>
  </body>
</html>

In the above code, the box element is positioned 50px offset from the upper left corner of the container element by setting the left and top parameters to 50px.

2. Z-index parameter

There may be multiple elements on the page for absolute positioning. If these elements overlap, the z-index parameter can be used to control the stacking order of the elements. Elements with larger z-index values are placed closer to the front and will cover other elements.

Code example:

<!DOCTYPE html>
<html>
  <head>
    <style>
      .container {
        position: relative;
        width: 400px;
        height: 400px;
        background-color: lightgray;
      }
      .box1 {
        position: absolute;
        left: 50px;
        top: 50px;
        width: 200px;
        height: 200px;
        background-color: red;
        z-index: 1;
      }
      .box2 {
        position: absolute;
        left: 100px;
        top: 100px;
        width: 200px;
        height: 200px;
        background-color: blue;
        z-index: 2;
      }
    </style>
  </head>
  <body>
    <div class="container">
      <div class="box1"></div>
      <div class="box2"></div>
    </div>
  </body>
</html>

In the above code, the z-index value of the box1 element is 1, and the z-index value of the box2 element is 2, so the box2 element will cover the box1 element above.

3. Position the position attribute of the parent element

When performing absolute positioning, you need to pay attention to the position attribute of the parent element. If the position attribute is not set on the positioned parent element, the position of the absolutely positioned element will be positioned relative to the visible area of the document. If the positioned parent element has the position attribute set, the position of the absolutely positioned element will be positioned relative to the positioned parent element.

Code example:

<!DOCTYPE html>
<html>
  <head>
    <style>
      .container {
        position: relative;
        width: 400px;
        height: 400px;
        background-color: lightgray;
      }
      .box1 {
        position: absolute;
        left: 50px;
        top: 50px;
        width: 200px;
        height: 200px;
        background-color: red;
      }
      .box2 {
        position: absolute;
        left: 100px;
        top: 100px;
        width: 200px;
        height: 200px;
        background-color: blue;
      }
    </style>
  </head>
  <body>
    <div class="container">
      <div class="box1"></div>
      <div class="box2"></div>
    </div>
  </body>
</html>

In the above code, the positioning parent element of the box1 and box2 elements is the container element, so the box1 and box2 elements are positioned relative to the container element.

Absolute positioning is a very common layout method in front-end development. By referring to the above parameters, elements can be positioned flexibly and accurately. In actual development, we can flexibly use these parameters according to needs to achieve diverse page layouts.

The above is the detailed content of In absolute positioning, what parameters can be used as a reference?. For more information, please follow other related articles on the PHP Chinese website!

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Next Level CSS Styling for CursorsApr 23, 2025 am 11:04 AM

Custom cursors with CSS are great, but we can take things to the next level with JavaScript. Using JavaScript, we can transition between cursor states, place dynamic text within the cursor, apply complex animations, and apply filters.

Worlds Collide: Keyframe Collision Detection Using Style QueriesApr 23, 2025 am 10:42 AM

Interactive CSS animations with elements ricocheting off each other seem more plausible in 2025. While it’s unnecessary to implement Pong in CSS, the increasing flexibility and power of CSS reinforce Lee's suspicion that one day it will be a

Using CSS backdrop-filter for UI EffectsApr 23, 2025 am 10:20 AM

Tips and tricks on utilizing the CSS backdrop-filter property to style user interfaces. You’ll learn how to layer backdrop filters among multiple elements, and integrate them with other CSS graphical effects to create elaborate designs.

SMIL on?Apr 23, 2025 am 09:57 AM

Well, it turns out that SVG's built-in animation features were never deprecated as planned. Sure, CSS and JavaScript are more than capable of carrying the load, but it's good to know that SMIL is not dead in the water as previously

'Pretty' is in the eye of the beholderApr 23, 2025 am 09:40 AM

Yay, let's jump for text-wrap: pretty landing in Safari Technology Preview! But beware that it's different from how it works in Chromium browsers.

CSS-Tricks Chronicles XLIIIApr 23, 2025 am 09:35 AM

This CSS-Tricks update highlights significant progress in the Almanac, recent podcast appearances, a new CSS counters guide, and the addition of several new authors contributing valuable content.

Tailwind's @apply Feature is Better Than it SoundsApr 23, 2025 am 09:23 AM

Most of the time, people showcase Tailwind's @apply feature with one of Tailwind's single-property utilities (which changes a single CSS declaration). When showcased this way, @apply doesn't sound promising at all. So obvio