border

Container(
                    // color: Colors.yellow,
                    margin: EdgeInsets.only(left: 15, right: 7),
                    decoration: BoxDecoration(
                      color: Colors.white,
                      borderRadius: BorderRadius.circular(5),
                      border: Border.all(color: Color(0xff667EF5), width: 0.5),
                    ),
                    height: 40,
                    child: TextButton(
                      child: Text(
                        "添加成员", style: TextStyle(color: Color(0xff3D77E5)),),
                      onPressed: () {},
                    ),
                    // width: window
                  )