        try {
            const response = await fetch('./909-questions.json');
            const data = await response.json();
            this.questions = data.filter(q => !this.correctQuestions.some(cq => cq.question === q.question));
          } catch (error) {
            console.error('加载题目失败:', error);
            alert('加载题目失败，请检查网络连接。');
          }
          this.loading = false; // 加载完成后设置加载状态为 false
        },
        renderMarkdo