CSS Basic

CSS HOME
CSS Introduction
CSS Syntax
CSS Id & Class
CSS How To

CSS Styling

Styling Backgrounds
Styling Text
Styling Fonts
Styling Links
Styling Lists
Styling Tables

CSS Box Model

CSS Box Model
CSS Border
CSS Outline
CSS Margin
CSS Padding

CSS Advanced

CSS Grouping/Nesting
CSS Dimension
CSS Display
CSS Positioning
CSS Floating
CSS Align
CSS Pseudo-class
CSS Pseudo-element
CSS Navigation Bar
CSS Image Gallery
CSS Image Opacity
CSS Image Sprites
CSS Media Types
CSS Attribute Selectors
CSS Don't
CSS Summary

CSS Examples

CSS Examples

CSS Quiz

CSS Quiz
CSS Certificate

CSS References

CSS Reference
CSS Reference A to Z
CSS Reference Aural
CSS Web Safe Fonts
CSS Units
CSS Colors
CSS Colorvalues
CSS Colornames

CSS Image Opacity / Transparency

« Previous Next Chapter »

Creating transparent images with CSS is easy.


Examples

Try it Yourself - Examples

Creating transparent images - mouseover effect

Creating a transparent box with text on a background image


Note: This is not yet a CSS standard. However, it works in all modern browsers, and is a part of the W3C CSS 3 recommendation.

Example 1 - Creating a Transparent Image

First we will show you how to create a transparent image with CSS.

Regular image:

klematis

The same image with transparency:

klematis

Look at the following source code:

<img src="klematis.jpg" width="150" height="113" alt="klematis"
style="opacity:0.4;filter:alpha(opacity=40)" />

Firefox uses the property opacity:x for transparency, while IE uses filter:alpha(opacity=x).

Tip: The CSS3 syntax for transparency is opacity:x.

In Firefox (opacity:x) x can be a value from 0.0 - 1.0. A lower value makes the element more transparent.

In IE (filter:alpha(opacity=x)) x can be a value from 0 - 100. A lower value makes the element more transparent.


Example 2 - Image Transparency - Mouseover Effect

Mouse over the images:

klematis klematis

The source code looks like this:

<img src="klematis.jpg" style="opacity:0.4;filter:alpha(opacity=40)"
onmouseover="this.style.opacity=1;this.filters.alpha.opacity=100"
onmouseout="this.style.opacity=0.4;this.filters.alpha.opacity=40" />

<img src="klematis2.jpg" style="opacity:0.4;filter:alpha(opacity=40)"
onmouseover="this.style.opacity=1;this.filters.alpha.opacity=100"
onmouseout="this.style.opacity=0.4;this.filters.alpha.opacity=40" />

We see that the first line of the source code is similar to the source code in Example 1. In addition, we have added an onmouseover attribute and an onmouseout attribute. The onmouseover attribute defines what will happen when the mouse pointer moves over the image. In this case we want the image to NOT be transparent when we move the mouse pointer over it.

The syntax for this in Firefox is: this.style.opacity=1 and the syntax in IE is: this.filters.alpha.opacity=100.

When the mouse pointer moves away from the image, we want the image to be transparent again. This is done in the onmouseout attribute.


Example 3 - Text in Transparent Box

This is some text that is placed in the transparent box. This is some text that is placed in the transparent box. This is some text that is placed in the transparent box. This is some text that is placed in the transparent box. This is some text that is placed in the transparent box.

The source code looks like this:

<html>
<head>
<style type="text/css">
div.background
  {
  width:500px;
  height:250px;
  background:url(klematis.jpg) repeat;
  border:2px solid black;
  }
div.transbox
  {
  width:400px;
  height:180px;
  margin:30px 50px;
  background-color:#ffffff;
  border:1px solid black;
  /* for IE */
  filter:alpha(opacity=60);
  /* CSS3 standard */
  opacity:0.6;
  }
div.transbox p
  {
  margin:30px 40px;
  font-weight:bold;
  color:#000000;
  }
</style>
</head>

<body>

<div class="background">
<div class="transbox">
<p>This is some text that is placed in the transparent box.
This is some text that is placed in the transparent box.
This is some text that is placed in the transparent box.
This is some text that is placed in the transparent box.
This is some text that is placed in the transparent box.
</p>
</div>
</div>

</body>
</html>

First, we create a div element (class="background") with a fixed height and width, a background image, and a border. Then we create a smaller div (class="transbox") inside the first div element. This div also have a fixed width, a background image, and a border. In addition we make this div transparent.

Inside the transparent div, we add some text inside a p element.


« Previous Next Chapter »

宏飞网络是你学习web开发、测试web程序实例、和培养职业技能的首选网站。我们提供例子也许有些简单,但对理解基本概念有帮助。

我们尽量避免在教程、参考及例子中出现错误,但不能保证所有的内容都是正确的。

你使用本网站时,我们默认你已经阅读并接受了我们的隐私政策。

Copyright 2003-2011宏飞网络 版权所有