css圆角属性是什么

#rcorners4 {

    border-radius: 15px 50px 30px 5px;

    background: #8AC007;

    padding: 20px;

    width: 200px;

    height: 150px;

}

#rcorners5 {

    border-radius: 15px 50px 30px;

    background: #8AC007;

    padding: 20px;

    width: 200px;

    height: 150px;

}

#rcorners6 {

    border-radius: 15px 50px;

    background: #8AC007;

    padding: 20px;

    width: 200px;

    height: 150px;

}