Buttons
Options
Use any of the available button classes to quickly create a styled button.
Sizes
Fancy larger or smaller buttons? Add .btn-lg, .btn-sm, or .btn-xs for additional sizes.
{% endhighlight %}
Create block level buttons—those that span the full width of a parent— by adding .btn-block.
Active state
Buttons will appear pressed (with a darker background, darker border, and inset shadow) when active. For <button> elements, this is done via :active. For <a> elements, it's done with .active. However, you may use .active on <button>s should you need to replicate the active state programmatically.
Button element
No need to add :active as it's a pseudo-class, but if you need to force the same appearance, go ahead and add .active.
{% highlight html %} {% endhighlight %}
Anchor element
Add the .active class to <a> buttons.
Disabled state
Make buttons look unclickable by fading them back 50%.
Button element
Add the disabled attribute to <button> buttons.
{% highlight html %} {% endhighlight %}
Cross-browser compatibility
If you add the disabled attribute to a <button>, Internet Explorer 9 and below will render text gray with a nasty text-shadow that we cannot fix.
Anchor element
Add the .disabled class to <a> buttons.
We use .disabled as a utility class here, similar to the common .active class, so no prefix is required.
Link functionality caveat
This class uses pointer-events: none to try to disable the link functionality of <a>s, but that CSS property is not yet standardized and isn't fully supported in Opera 18 and below, or in Internet Explorer 11. So to be safe, use custom JavaScript to disable such links.
Context-specific usage
While button classes can be used on <a> and <button> elements, only <button> elements are supported within our nav and navbar components.
Button tags
Use the button classes on an <a>, <button>, or <input> element.
Cross-browser rendering
As a best practice, we highly recommend using the <button> element whenever possible to ensure matching cross-browser rendering.
Among other things, there's a bug in Firefox <30 that prevents us from setting the line-height of <input>-based buttons, causing them to not exactly match the height of other buttons on Firefox.