Our sister article, entitled creating proper mouse-over borders explains how to add a clean border around an image link on hover, without the all-too-common and undesirable “jump” effect. In this article, we will explain in detail how to apply a border INSIDE an image itself, for those situations where an image may be displayed up against another element, or where a hidden margin would not be appropriate. Before we get started we should warn you that this technique is not (at this time) IE 5.5 friendly, but does work in Internet Explorer 6, 7, Firefox and Safari just fine. On to the code!

First, we will create the div to encase our image link. In contrast to our original mouse-over borders article, this one will not include the image within the div (we’ll explain this in just a moment). We will continue using the image of our furry friend for this article, and here’s the code we’ll start with: <div class="catwidth"><a href="#"></a></div>

Now, instead of adding the image directly into our div, we will need to define this image in the background of the div that we are using. If you are only planning on using this code in one place, you can simply use this css to do it:.catwidth a{width:130px;height:130px;border:0; background-image:url(images/cat.jpg);display:block;}
.catwidth a:hover {border:3px solid #5f9215;
width:124px;height:124px;background-position:center;}What we have done here is told the browser that we have a 130 pixel image link, but on mouseover we would like it to remove three pixels on each side (to 124 pixels), replacing it with a three pixel border. Now, the way we get around the image jumping and becoming displaced is by adding background-position:center, which orders the browser to maintain the same position for the image, even if it has been clipped on all edges by three pixels. Make sense?

Here is our end result:

This is great for one image, but let’s say that you have three different places on a page that you would like to apply the same effect to. You could create three distinct classes, but a much easier method (if all three images are the same size) would be to simply change your div code to look like this:<div class="catwidth" style="background-image:url(images/second-image.gif);" ><a href="#"></a></div>

This will override the image defined within your stylesheet, and render second-image.gif in its place. As we mentioned, this will only work if the images are all the same size. This is because, while we can define width and height just fine within the style variable of our div, we can’t define what will happen on mouseover. So, we could add an image at twice that size and declare as such in our div, but as soon as the image is moused over it would go back to what is defined within the stylesheet.

Compatibility:
This method has been tested in and is compatible with Internet Explorer 6, 7, Firefox (PC and Mac), Netscape and Safari (PC and Mac). Note that at the present time, IE 5.5 is not supported.

That’s all folks!
If you have an idea or article that you would like to contribute, send it on! We’re always looking for good, quality articles. Note that we will not republish an article that has been published elsewhere, so keep it original!

Recently, we have noticed a number of prominent web sites that suffer from an all-too-common problem: jumping or displaced mouse-over effects. For an example of what we’re talking about, run your mouse over this image:

What’s happening here is that a border (in this case a solid, 3 pixel border) has been applied to this image on mouseover, but has not been applied (and also not accounted for) before the mouseover.

Simply put, the problem is that when a visitor runs their mouse over the image, it not only adds the border, it also shifts the content around it in a jerking motion.

Note: The code above has been modified to be Internet Explorer 6 compliant. IE 6 has trouble properly assigning a border around a linked image tag without a sort of “call to action,” something that compels the browser to change the border option. Luckily for us, the first option we’ve outlined below not only fixes the image “jumping” issue, it also forces Internet Explorer 6 to do what it should. Our second option (below) accomplishes this with the addition of one short line of code.

Fix #1: Create an “invisible” image border

There are a couple of easy ways to fix this, depending on how your site is designed. If you have a site with a solid content background color (like ours), you can simply add a border with the same color code as your content background to the standard image link, like this:

The code we used to fix the problem is here:.catfixed a img{border:3px solid #fffaef /*this is the background color of our site*/;}
.catfixed a:hover img{border:3px solid #5f9215 /*our desired mouseover color*/;}Obviously, you can remove our notations before using it on your web site.

Fix #2: Creative use of margins

The first fix works fine if your site has a consistent background color, but what happens if your site has a background fade, or you want to apply the same style to items in different locations (with different colored backgrounds)? Instead of making multiple classes to accommodate each area, or resigning yourself to having a “jump” each time a visitor mouses over the affected item, we can simply replace our standard border with a margin instead, like this:.catmargin a img{margin:3px;border:0;}
.catmargin a:hover img{border:3px solid #5f9215; margin:0;}
.catmargin a:hover{margin:0; /*fixes IE 6*/}Don’t forget to zero out your margin on the image hover, or you will end up with the same jump that’s shown at the top of this article. Take a look at how this turns out, this time applied within a box that holds a background gradient.

Notice how the area around the image is still transparent, but there is no jump when the visitor mouses over the image.

Compare this to the first method under the same circumstances and you will see what we’re talking about here. To make the effect more obvious, we changed the initial, “invisible” border to a dark red:

Taking it further.

Now, there are ways to get a little more creative here, such as what CSS Design Yorkshire has done with the image links on their home page. In this case, the image jumps 1 pixel to the right and bottom, while keeping the content to the left and right intact. That last part is key, because it keeps what should be in focus emphasized, not the content that falls outside of the hover area. The text immediately below the image link jumps by 1 pixel as well, which serves as a light accent and an effective way to draw attention. The white-to-orange color choice also works well in this situation. Note that on this particular web site, the effect is not apparent in IE 6.

The point is, were this site to simply assign a border to the image on hover, the content all around the image would jump, making the site look unprofessional. But they took the time to do it right, and having a controlled, slight “bounce” as in this example adds emphasis to the item.

If you are interested in creating a mouseover image that has an inline border (one that does not increase the overall width or height of the image area), take a look at our sister article entitled creating an inline css image border.

Compatibility:
Both methods have been tested in and are compatible with Internet Explorer 5.5 and 6 (see above), 7, Firefox (PC and Mac), Netscape and Safari (PC and Mac).

That’s all folks!
If you have an idea or article that you would like to contribute, send it on! We’re always looking for good, quality articles. Note that we will not republish an article that has been published elsewhere, so keep it original!

Most of us have at one time or another have had to (or tried unsuccessfully to) alternate an image on mouse over. Most commonly, this is effect is used to provide a response when a visitor runs their mouse over a button, like the one below:

Now, this was very easy to create, using just the following CSS:
.buttonexample{background-image: url(images/button.gif); width:91px; height:28px;}
.buttonexample:hover{background-image: url(images/button-over.gif);}and the following html:
<div class="buttonexample"></div>

If you are just hoping to make a standard image change on mouseover, without having that image link to anything, then you are almost done. To prevent the hover image from “flashing” before loading, simply follow the steps listed on our sister article: A quick look: preloading images with css.

If, however you would like to have a mouseover effect on a linked image, it’s just a little bit more complex. In addition to the code above, we will add one more line to make this:
.buttonexample{background-image: url(images/button.gif); width:91px; height:28px;}
.buttonexample:hover{background-image: url(images/button-over.gif);}
.buttonexample a{display:block;width:91px;height:28px;}and the following html:
<div class="buttonexample"><a href="#"></a></div>

This is the simplest method, but is not compatible with IE 5.5/6. This is because IE 5.5 and 6 do not recognize the “hover” attribute when applied directly to a DIV. To make this button compatible, we’ll just need to define the same variables as we did on the standard div, but for the “a” tag, like this:
.buttonexample a{background-image: url(images/button.gif); display:block;width:91px;height:28px;}
.buttonexample a:hover{background-image: url(images/button-over.gif);

Now, we have this link. Remember to change the width and height of this link to correspond with the size of your image.

Compatibility:
This method has been tested in and is compatible with Internet Explorer 5.5 and 6 (see above), 7, Firefox (PC and Mac), Netscape and Safari (PC and Mac).

That’s all folks!

If you have an idea or article that you would like to contribute, send it on! We’re always looking for good, quality articles. Note that we will not republish an article that has been published elsewhere, so keep it original!