pod 'Masonry' 自动布局
//redView和父视图左边距10
[redView mas_makeConstraints:^(MASConstraintMaker *make) {
make.leading.equalTo(self.view.mas_leading).offset(10);
make.top.equalTo(self.view.mas_top).offset(30);
make.width.equalTo(blueView.mas_width).offset(0);
make.height.equalTo(@150);
}];