Correct way to create rounded corners in Twitter Bootstrap

I've just started with Twitter Bootstrap and here is one question.

I am creating custom <header> block, and I want it's bottom corners to be rounded.

Is there any "correct" way to do this by using predefined classes, or I have to specify it manually like:

border-radius: 10px;               // and all that cross-browser trumpery

For now, I'm using css styles. Maybe it will be better to use less for that issue?

How do I create a rounded circle in Bootstrap?

To create a rounded circle with Bootstrap, use the rounded-circle class.

Which class in Bootstrap used to provide rounded corners to the border is?

Border-radius Add classes to an element to easily round its corners.

Which Bootstrap 4 class is used to add rounded corners to an image?

img-rounded − You can make rounded corners to an image by using . rounded class.

Which of these would give a block element rounded corners?

With the CSS border-radius property, you can give any element "rounded corners".

<div class="img-rounded"> will give you rounded corners.

Related questions