Update 13 files

- /TeacherDashboard/index.html
- /TeacherDashboard/TeacherDashboard.code-workspace
- /TeacherDashboard/components/resourceModal.html
- /TeacherDashboard/components/subjectModal.html
- /TeacherDashboard/components/topicModal.html
- /TeacherDashboard/js/main.js
- /TeacherDashboard/js/subjects/colors.js
- /TeacherDashboard/js/subjects/subjectManager.js
- /TeacherDashboard/js/subjects/SubjectModel.js
- /TeacherDashboard/js/subjects/SubjectStorage.js
- /TeacherDashboard/js/topics/TopicModel.js
- /TeacherDashboard/js/topics/topicManager.js
- /TeacherDashboard/styles/main.css

TeacherDashboard/js/subjects/SubjectStorage.js

@@ -0,0 +1,39 @@
+export class SubjectStorage {
+    constructor() {
+        this.storageKey = 'teacherDash_subjects';
+    }
+
+    async getAllSubjects() {
+        try {
+            const data = localStorage.getItem(this.storageKey);
+            return data ? JSON.parse(data) : [];
+        } catch (error) {
+            console.error('Error loading subjects:', error);
+            return [];
+        }
+    }
+
+    async saveSubject(subject) {
+        try {
+            const subjects = await this.getAllSubjects();
+            const existingIndex = subjects.findIndex(s => s.id === subject.id);
+
+            if (existingIndex >= 0) {
+                subjects[existingIndex] = subject;
+            } else {
+                subjects.push(subject);
+            }
+
+            localStorage.setItem(this.storageKey, JSON.stringify(subjects));
+            return subject;
+        } catch (error) {
+            throw new Error('Failed to save subject: ' + error.message);
+        }
+    }
+
+    async deleteSubject(subjectId) {
+        const subjects = await this.getAllSubjects();
+        const filtered = subjects.filter(s => s.id !== subjectId);
+        localStorage.setItem(this.storageKey, JSON.stringify(filtered));
+    }
+}