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Border Radius: Part 2

Border Radius: Part 2


In this video, you'll learn about several border-radius syntactic features beyond just rounding off the four corners. Additionally, you'll learn several practical tips to keep in mind when using border-radius.

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    [? music playing ?]

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    [Think Vitamin Membership, membership.thinkvitamin.com]

  • 0:07

    [CSS3 Borders, Border Radius: Part 2 with Nick Pettit]

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    Everything I've shown you so far will work in Chrome,

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    Safari, and Firefox.

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    However, there are a few more things to learn about the Border Radius Property.

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    But don't worry, I'll point out the browser compatibility issues along the way.

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    With that said, there is an alternative

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    shorthand syntax that we can use to target individual corners.

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    If we use the Border Radius property on its own

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    and then type in four consecutive values

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    separated by spaces,

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    we can target the corners in a clockwise

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    order starting with the upper-left corner.

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    Now if we refresh the browser,

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    we can see that each one of these corners has a

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    slightly different curvature applied to it.

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    It's very important to point out here that this

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    only works in Chrome and Firefox,

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    but it does not currently work in Safari.

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    And just so you can see, here's how it works

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    in Firefox.

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    Just as you'd expect.

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    Just copy and paste there.

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    And I'll flip over to Firefox, and it looks just like that.

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    Now, what I've shown you so far will work just fine if you want your

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    borders to be perfectly round.

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    However, we can take things a step further and create corners that have

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    an oval or an oblong shape to them.

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    To do this, I will delete what we have so far here,

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    and we'll type webkit-border-radius:,

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    and we'll put two values

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    into the border radius property.

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    And then we'll separate those two values with a slash.

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    And the syntax for Mozilla is

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    exactly the same except for the vendor prefix.

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    The value before the slash

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    will represent the horizontal radius

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    measuring from the corner.

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    The larger the first value is, the wider the curve will appear.

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    The second value is the vertical height of the radius.

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    The larger the second value is, the taller the

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    curve will appear.

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    If we switch back to our browsers,

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    we can see that the border radii are

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    no longer perfectly round and that they have taken

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    on a more oblong shape.

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    And here's what it looks like in Firefox.

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    This trick will work in Chrome and Firefox,

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    but it does not currently work in the latest release of Safari.

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    Now that you know how Border Radius works,

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    let's take a look at some more practical tips to keep in mind when using Border Radius.

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    First, I want to show you one of my favorite tricks.

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    Here we have our same example div as before,

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    without any styling applied.

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    Now, in our style sheet, we can apply a border radius,

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    and we'll set the border radius to

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    a really high value.

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    When we switch back to our browser and refresh the page,

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    you can see that our four-cornered div now

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    looks like a circle.

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    The reason for this is that we've curved our corners so much,

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    the radii are intersecting one another.

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    A nice way to use this might be to highlight a piece of text.

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    You could put a border on your element

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    and make the background color of the element the same as the element behind it.

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    This will create a circle that you can use to lasso up

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    important pieces of text or images.

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    There is a really cool example of this on the web that I'd like to show you.

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    This animated map of the solar system was created entirely in CSS3.

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    [CSS3 Solar System, Alex Giron neography.com/experiment/circles/solarsystem/]

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    The planets are actually just boxes that have a high border radius

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    value applied to them to the point that they look like circles.

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    Pretty neat.

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    Just as a point of style, it's difficult to say arbitrarily

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    when you should use Border Radius and when you shoud not.

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    Really, it depends on the context.

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    What I say is, use it sparingly.

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    Border Radius is a really cool effect, so it's easy to overuse

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    it and curve everything.

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    Already there's lots of sites on the web that are very obviously

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    using Border Radius, because every box on their site has large,

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    rounded corners and they're just using it all over the place.

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    Don't fall into this trap just because you want to show off your

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    Border Radius skills.

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    Instead, you can actually do a lot to soften up the look of your site

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    in a very subtle way.

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    Instead of rounding off every corner on your site with curves,

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    try to use Border Radius sparingly.

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    So, for example, when you apply a border radius,

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    try applying a much lower value, like 10 pixels,

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    or even 5 pixels.

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    Using Border Radius this way tends to make

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    sites look and feel more natural.

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    Finally, you probably noticed that I made no mention of Internet Explorer.

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    That's because all current releases of IE do not

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    support Border Radius at all.

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    However, there is a platform preview of Internet Explorer 9 available now.

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    [IE9 Platform Preview http://ie.microsoft.com/testdrive/]

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    IE9 will indeed offer support for Border Radius.

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    If you target Google Chrome 5 or the platform preview

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    of Internet Explorer 9, you can

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    actually use the Border Radius property without any

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    browser prefixes, like so.

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    IE9 is expected to be released in 2011.

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    So, as you've just seen, Border Radius is a

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    very fast way to create rounded corners

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    without the use of images, tables, or other markup hacks.

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    It's a great tool for making boxy-looking sites feel

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    a lot more organic.

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