CSS 3 border-radius

HTML

<!DOCTYPE html>
<html>
    <div id="example_A"><span>Example A</span></div>
    
    <div id="example_B"><span>Example B</span></div>
    
    <div id="example_C"><span>Example C</span></div>

    <div id="example_D"><span>Example D</span></div>
</html>

CSS

body
{
    font-family:Segoe UI;
}
div
{
    width:100px;
    height:100px;
    color:#fff;
    background-color: rgb(0,113,188);
    margin:40px;
    float:left;
    text-align:center;    
}

div > span
{
    position:relative;
    top:35px;
}

#example_A
{
    border-radius: 10px;
}

#example_B
{
    border-top-left-radius:10px 25px;
}

#example_C
{
    border-radius: 50px;
 
}

#example_D
{
    border-bottom-right-radius: 150px; 
}