Another exciting new border feature of CSS3 is the property border-image. With this feature you can define an image to be used instead of the normal border of an element. This feature is actually split up into a couple of properties: border-image and border-corner-image. These two values are shorthands for:
border-image:
border-top-imageborder-right-imageborder-bottom-imageborder-left-image
border-corner-image:
border-top-left-imageborder-top-right-imageborder-bottom-left-imageborder-bottom-right-image
border-image currently works in Safari and Firefox 3.1 (Alpha). The syntax to use it is:
border-image: url(border.png) 27 27 27 27 round round;
Which results in:
Lorem ipsum dolor sit amet.
Or:
border-image: url(border.png) 27 27 27 27 stretch stretch;
Which then results in:
Lorem ipsum dolor sit amet.
For those of you not so lucky as to be able to see this, here are screenshots of the two examples.
Number one:
Number two:
The new CSS3 property border-image is a little tricky, but it can allow you to create flexible boxes with custom borders (or drop shadows, if that’s your thing) with a single div and a single image. In this article I explain how the border-image shorthand property works in today’s browsers.
The basic idea
The border-image shorthand property has 3 parts:
border-image: url(border-image.png) 25% repeat;
Essentially, these allow you to specify:
- An image to use as the border
- Where to slice that image, dividing the image into 9 sections
- How the browser should apply those sections to the edges of your element
The pertinent details
Let’s look at each part of the process in a little more detail. The first part is easy, and is familiar from the background-image property. For demonstration purposes I’ll use this image, which is 100px x 100px:
Slicing your image
The second part can have from one to four values, much like the border-width property, and they are specified in the same order: top, right, bottom, left. You can use percentages or pixels. Strangely, the percentages require the “%”, while pixels should be listed without the “px”:
border-image: url(my-image.gif) 25% 30% 10% 20% repeat;
border-image: url(my-image.gif) 25 30 10 20 repeat;
In this case, since my image is 100px x 100px, the two rules above are equivalent – they slice the image in the same places. I’ve added some dimensions on my image to demonstrate:
Repeat, Round, Stretch
border-image will always place the corner sections of your image into the corresponding corners of your element box, but the third part of the shorthand rule tells the browser how to treat the middle sections of your image — the ones that will go along the edges of your element. Repeat (repeat, or tile, the image) and stretch (stretch, or scale, the image) are pretty self-explanatory. Round means tile the image but only so that a whole number of tiles fit, and otherwise scale the image. Right now, Safari and Chrome interpret round asrepeat. There can be up to two values: one for the top and bottom edges of the element, and one for the left and right. Here’s an example with the top/bottom value set to repeat, and the left/right value set to stretch:
#example-one {
border-width:25px 30px 10px 20px;
-moz-border-image:url("border-image.png") 25 30 10 20 repeat stretch;
-webkit-border-image:url("border-image.png") 25 30 10 20 repeat stretch;
border-image:url("border-image.png") 25 30 10 20 repeat stretch;
}
Screenshot for Example One
LIVE DEMO, RSS READERS CLICK OVER TO SEE. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean eu arcu non dui consequat vestibulum non vitae eros. Donec imperdiet lorem at mi rhoncus lacinia. Phasellus porttitor ligula eu justo condimentum eget placerat arcu pharetra. Proin fringilla vulputate eros in accumsan. Sed mi nibh, pulvinar eu sollicitudin ut, feugiat non ipsum. In ornare, quam sit amet tempor suscipit, erat odio suscipit nisi, eu gravida nisl orci ut arcu. Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Border-width
border-image won’t do anything if you don’t specify a width for your border. For browsers that understand border-image, your image slices will be scaled to the specified width. If you use the border shorthand property, it provides a nice fallback for browsers that don’t:
#example-two {
border:50px double orange;
-moz-border-image:url("border-image.png") 25 30 10 20 repeat;
-webkit-border-image:url("border-image.png") 25 30 10 20 repeat;
border-image:url("border-image.png") 25 30 10 20 repeat;
}
Screenshot of Example Two
LIVE DEMO, RSS READERS CLICK OVER TO SEE.Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean eu arcu non dui consequat vestibulum non vitae eros. Donec imperdiet lorem at mi rhoncus lacinia. Phasellus porttitor ligula eu justo condimentum eget placerat arcu pharetra. Proin fringilla vulputate eros in accumsan. Sed mi nibh, pulvinar eu sollicitudin ut, feugiat non ipsum. In ornare, quam sit amet tempor suscipit, erat odio suscipit nisi, eu gravida nisl orci ut arcu. Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Or you can specify each width individually (in this example I’ve specified widths such that the image slices aren’t scaled at all):
#example-three {
border-color:orange;
border-style:double;
border-width:25px 30px 10px 20px;
-moz-border-image:url("border-image.png") 25 30 10 20 repeat;
-webkit-border-image:url("border-image.png") 25 30 10 20 repeat;
border-image:url("border-image.png") 25 30 10 20 repeat;
}
Screenshot of Example Three
LIVE DEMO, RSS READERS CLICK OVER TO SEE. dolor sit amet, consectetur adipiscing elit. Aenean eu arcu non dui consequat vestibulum non vitae eros. Donec imperdiet lorem at mi rhoncus lacinia. Phasellus porttitor ligula eu justo condimentum eget placerat arcu pharetra. Proin fringilla vulputate eros in accumsan. Sed mi nibh, pulvinar eu sollicitudin ut, feugiat non ipsum. In ornare, quam sit amet tempor suscipit, erat odio suscipit nisi, eu gravida nisl orci ut arcu. Lorem ipsum dolor sit amet, consectetur adipiscing elit.
Using a plain border at the same widths as your border-image won’t always be ideal, however, so you may want to use conditional stylesheets to give IE some different border styles altogether.
Browser quirks
Predictably, IE doesn’t understand anything of border-image. Browsers that do support border-image only support the shorthand property, not all the individual properties that aredescribed in the spec. Some potentially useful properties aren’t supported at all, especiallyborder-image-outset, which would solve this problem.
Also, the default behavior is supposed to be to discard the center section of the image, and use the ‘fill’ keyword on the border-image-slice property to preserve it:
The ‘fill’ keyword, if present, causes the middle part of the border-image to be preserved. (By default it is discarded, i.e., treated as empty.) (Read the spec)
But the current browser behavior is to preserve the middle, and there is no way to turn it off. Thus, if you don’t want your element’s content area to have a background, the center section of your image must be empty. However, you can use this filling behavior to your advantage, to create a box with a fancy border and background, with only one image.
Interactive demo
I built a border-image demo page to help me get my head around this complicated new set of CSS3 properties. You can pick an image, specify repeat, round, or stretch, and adjust the border-width and slicing. Enjoy!
Examples in the wild
CSS3 makes it possible to specify an image as an element’s border, instead of just a solid color. While on the surface this doesn’t seem particularly interesting, the way the property works makes it more than that which meets the eye. The border-image property lets you specify a single image for the purpose and then slices that image to create the desired border effect. Yes, CSS is slicing now. border-image is currently supported in all the modern browsers to various degrees except IE (as of IE9). The shorthand syntax is:
border-image: url(image.png) 25 40 12 10 stretch;
Where:
- url: The image that should be used as the border image.
- slicevalues: Up to four numbers that specify where the browser should slice the image:
-
The 1st value sets the offset of the first horizontal cut from the top of the image. For pixel units, do NOT include the “px” suffix.
-
The 2nd value sets the offset of the second vertical cut from the right edge of the image.
-
The 3rd value sets the offset of the third horizontal cut from the bottom of the image.
-
The 4th value sets the offset of the fourth vertical cut from the left edge of the image.
- stretch: How the slices should be oriented inside the element’s border. Valid values are “stretch”, “repeat”, “round”, or “space”.
For slicevalues, if only one number is defined, the same value will be used for all 4 cuts. If 2 numbers are defined, the first is used for the top and bottom cuts, and the second the left and right cuts. Regardless, 4 cuts are made to the image in total, and the browser ends up with 9 slices that it uses to put together the border image of an element. Each slice is used to fill the corresponding edges of the element’s border, with the center slice covering the element itself (and should be made transparent in most cases).
This post isn’t about a detailed description of border-image– that will have to be for another post. For this post, what I want to demonstrate is how to use this property to easily add image frames to containers on your page. First, create the image you’d like to use as the frame; here I’ve whipped up 2 simple frames to illustrate the technique:
Note that both images above have a transparent inside so the content they are framing can show through.
Now, to the heart of the matter- to add an image border to an element, define the border-image property with slicevalues that cut up the image as desired. Also define a border-width property echoing those values. Enough talk, to some examples now! Note that the below examples do not work in IE (as of IE9):
Example 1:
Found across much of the tropics, the coconut is known for its great versatility as seen in the many domestic, commercial, and industrial uses of its different parts. Coconuts are part of the daily diet of many people. Its endosperm is known as the edible “flesh” of the coconut; when dried it is called copra. The oil and milk derived from it are commonly used in cooking and frying; coconut oil is also widely used in soaps and cosmetics. The clear liquid coconut water within is a refreshing drink and can be processed to create alcohol. The husks and leaves can be used as material to make a variety of products for furnishing and decorating. It also has cultural and religious significance in many societies that use it. -Wikipedia
CSS:
.imageborder{
border-width: 20px;
-moz-border-image: url(frame.gif) 20 stretch; /*Mozilla version*/
-webkit-border-image: url(frame.gif) 20 stretch; /*Webkit version*/
-o-border-image: url(frame.gif) 20 stretch; /*Opera version*/
-ms-border-image: url(frame.gif) 20 stretch; /*IE syntax when it does support this prop*/
border-image: url(frame.gif) 20 stretch; /*Standard version*/
}
Markup:
<div style=”width:50%;min-height:150px”>
Content text here…
</div>
Example 2:
CSS: Same as above.
Markup:
<img src=”coconut.jpg” />
Example 3:
CSS:
.imageborder2{
border-width: 25px 30px;
-moz-border-image: url(frame2.png) 25 30 stretch;
-webkit-border-image: url(frame2.png) 25 30 stretch;
-o-border-image: url(frame2.png) 25 30 stretch;
-ms-border-image: url(frame2.png) 25 30 stretch;
border-image: url(frame2.png) 25 30 stretch;
}.
Markup:
<div style=”width:470px;height:300px;background:url(ocean_thumb.jpg) center center no-repeat”>
</div>
If you have other examples on live sites, I’d love to see them. Leave a link in the comments!
Like this:
Like Loading...
Denno Secqtinstien