diff --git a/public/admin.html b/public/admin.html
index 6175c1b..a94c9ea 100644
--- a/public/admin.html
+++ b/public/admin.html
@@ -76,6 +76,7 @@
             <input id="cd-color-input" type="color">
             <label class="checkbox-label"><input type="checkbox" id="cd-archived"> Archived</label>
             <button type="submit">Save</button>
+            <button type="button" id="cd-duplicate" class="secondary">Duplicate course</button>
             <button type="button" id="cd-delete" class="danger">Delete course</button>
           </form>
         </div>
diff --git a/public/admin.js b/public/admin.js
index 9f11c5f..2f86cc3 100644
--- a/public/admin.js
+++ b/public/admin.js
@@ -280,6 +280,13 @@ $('#course-meta-form').addEventListener('submit', async (e) => {
   openCourseDetail(currentCourseId);
 });
 
+$('#cd-duplicate').addEventListener('click', async () => {
+  const { id } = await api(`/api/courses/${currentCourseId}/duplicate`, { method: 'POST' });
+  currentCourseId = id;
+  showPanel('course-detail');
+  msg('Course duplicated — update the name and details below.');
+});
+
 $('#cd-delete').addEventListener('click', async () => {
   if (!confirm('Delete this whole course, including all units, items, and grades?')) return;
   await api(`/api/courses/${currentCourseId}`, { method: 'DELETE' });
diff --git a/public/styles.css b/public/styles.css
index dd6df45..6bf5cdc 100644
--- a/public/styles.css
+++ b/public/styles.css
@@ -214,9 +214,9 @@ button.danger { background: var(--bad); }
 .inline-form input { flex: 1; min-width: 140px; }
 
 .item-row {
-  display: flex; align-items: center; gap: 0.75rem;
-  background: var(--card); border-radius: 12px; padding: 0.75rem 1rem; margin: 0.5rem 0;
-  box-shadow: 0 2px 6px rgba(45, 49, 66, 0.06);
+  display: flex; align-items: center; gap: 0.6rem;
+  background: var(--card); border-radius: 10px; padding: 0.45rem 0.75rem; margin: 0.2rem 0;
+  box-shadow: 0 1px 4px rgba(45, 49, 66, 0.06);
   flex-wrap: wrap;
 }
 .item-row .grow { flex: 1; min-width: 120px; }
@@ -349,9 +349,29 @@ table.results tr:nth-child(even) td { background: #faf7ee; }
 }
 
 .checkbox-label { display: inline-flex; align-items: center; gap: 0.4rem; font-weight: 400; margin-right: 1rem; }
+/* admin-card sets label { flex-direction: column } — override for checkboxes */
+.admin-card .checkbox-label { flex-direction: row; font-size: 1rem; }
 .color-dot { width: 14px; height: 14px; border-radius: 50%; display: inline-block; flex-shrink: 0; }
 .archived-badge { background: #e8e2d0; color: var(--muted); font-size: 0.75rem; padding: 0.2rem 0.5rem; border-radius: 999px; }
 
+/* ---------- roster chips ---------- */
+#cd-roster { display: flex; flex-wrap: wrap; gap: 0.5rem; }
+#cd-roster .checkbox-label {
+  margin-right: 0;
+  background: #f7f2e3; border: 1.5px solid #d8d2c0; border-radius: 999px;
+  padding: 0.3rem 0.85rem; cursor: pointer; font-size: 0.95rem;
+  transition: background 0.12s, border-color 0.12s;
+}
+#cd-roster .checkbox-label:hover { border-color: var(--accent); }
+
+/* ---------- admin list panels — 2-col grid on wider screens ---------- */
+#course-rows, #student-rows {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
+  gap: 0.4rem;
+}
+#course-rows .item-row, #student-rows .item-row { margin: 0; }
+
 button.small { font-size: 0.85rem; padding: 0.4rem 0.8rem; }
 button.tiny { font-size: 0.75rem; padding: 0.15rem 0.5rem; }
 .hint.tiny { font-size: 0.8rem; margin: 0.25rem 0; }
diff --git a/server.js b/server.js
index caf09bf..c6ca6aa 100644
--- a/server.js
+++ b/server.js
@@ -479,6 +479,43 @@ app.delete('/api/courses/:id', requirePin, (req, res) => {
   res.json({ ok: true });
 });
 
+app.post('/api/courses/:id/duplicate', requirePin, (req, res) => {
+  const src = db.prepare(`SELECT name, subject, color FROM courses WHERE id = ?`).get(req.params.id);
+  if (!src) return res.status(404).json({ error: 'No such course' });
+
+  const newCourseId = db.prepare(`INSERT INTO courses (name, subject, color) VALUES (?, ?, ?)`)
+    .run(`Copy of ${src.name}`, src.subject || '', src.color || '#4f86f7').lastInsertRowid;
+
+  const insUnit = db.prepare(`INSERT INTO units (course_id, name, sort) VALUES (?, ?, ?)`);
+  const insItem = db.prepare(`
+    INSERT INTO items (unit_id, type, title, body, points, ref_id, sort, due_date, allow_retakes, prereq_item_id, evidence_mode, retake_policy)
+    VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+  `);
+  const insQ = db.prepare(`INSERT INTO quiz_questions (item_id, type, prompt, choices, correct_answer, points, sort) VALUES (?, ?, ?, ?, ?, ?, ?)`);
+  const getItems = db.prepare(`SELECT * FROM items WHERE unit_id = ? ORDER BY sort, id`);
+  const getQs = db.prepare(`SELECT * FROM quiz_questions WHERE item_id = ? ORDER BY sort, id`);
+
+  const units = db.prepare(`SELECT id, name, sort FROM units WHERE course_id = ? ORDER BY sort, id`).all(req.params.id);
+  for (const u of units) {
+    const newUnitId = insUnit.run(newCourseId, u.name, u.sort).lastInsertRowid;
+    for (const it of getItems.all(u.id)) {
+      const newItemId = insItem.run(
+        newUnitId, it.type, it.title, it.body, it.points, it.ref_id,
+        it.sort, it.due_date, it.allow_retakes,
+        null, // prereq_item_id: don't copy — old IDs won't match new items
+        it.evidence_mode || 'none', it.retake_policy || 'latest'
+      ).lastInsertRowid;
+      if (it.type === 'quiz') {
+        for (const q of getQs.all(it.id)) {
+          insQ.run(newItemId, q.type, q.prompt, q.choices, q.correct_answer, q.points, q.sort);
+        }
+      }
+    }
+  }
+
+  res.json({ id: newCourseId });
+});
+
 app.post('/api/courses/:id/enroll', requirePin, (req, res) => {
   db.prepare(`INSERT OR IGNORE INTO enrollments (student_id, course_id) VALUES (?, ?)`)
     .run(req.body.studentId, req.params.id);