-- 毛玻璃效果

// UIBlurEffectStyleLight UIBlurEffectStyleExtraLight UIBlurEffectStyleDark
UIBlurEffect *effect = [UIBlurEffect effectWithStyle:UIBlurEffectStyleExtraLight];
UIVisualEffectView *effectView = [[UIVisualEffectView alloc] initWithEffect:effect];
[self.view addSubview:effectView];
[effectView mas_makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(self.tableView.mas_top).with.offset(ALL_HEIGHT(100/2));
make.left.equalTo(self.tableView.mas_left);
make.right.equalTo(self.tableView.mas_right);
make.height.mas_equalTo(ALL_HEIGHT(100/2));
}];