diff --git a/frontend/src/pages/ChallengeDetail.jsx b/frontend/src/pages/ChallengeDetail.jsx
index b824bc5..b62335a 100644
--- a/frontend/src/pages/ChallengeDetail.jsx
+++ b/frontend/src/pages/ChallengeDetail.jsx
@@ -312,9 +312,9 @@ export default function ChallengeDetail() {
                         borderRadius: '0.5rem'
                       }}
                     >
-                      <div style={{ flex: 1, minWidth: 0 }}>
-                        <div style={{ fontWeight: 500 }}>{friend.username}</div>
-                        <div style={{ fontSize: '0.875rem', color: 'var(--text-muted)' }}>{friend.email}</div>
+                      <div style={{ flex: 1, minWidth: 0, overflow: 'hidden' }}>
+                        <div style={{ fontWeight: 500, overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>{friend.username}</div>
+                        <div style={{ fontSize: '0.875rem', color: 'var(--text-muted)', overflow: 'hidden', textOverflow: 'ellipsis', whiteSpace: 'nowrap' }}>{friend.email}</div>
                       </div>
                       <button
                         className="btn btn-primary btn-sm"