diff --git a/frontend/app/(main)/mail/imap/page.tsx b/frontend/app/(main)/mail/imap/page.tsx
index f66229bd..cf734b8a 100644
--- a/frontend/app/(main)/mail/imap/page.tsx
+++ b/frontend/app/(main)/mail/imap/page.tsx
@@ -13,6 +13,17 @@ import {
   DialogTitle,
   DialogFooter,
 } from "@/components/ui/dialog";
+import {
+  AlertDialog,
+  AlertDialogAction,
+  AlertDialogCancel,
+  AlertDialogContent,
+  AlertDialogDescription,
+  AlertDialogFooter,
+  AlertDialogHeader,
+  AlertDialogTitle,
+} from "@/components/ui/alert-dialog";
+import { toast } from "sonner";
 import { Switch } from "@/components/ui/switch";
 import {
   ResizablePanelGroup,
@@ -44,6 +55,8 @@ import {
   FolderOpen,
   Send,
   Download,
+  Eye,
+  EyeOff,
 } from "lucide-react";
 import DOMPurify from "isomorphic-dompurify";
 import {
@@ -115,6 +128,9 @@ export default function ImapMailPage() {
   const [composeInReplyTo, setComposeInReplyTo] = useState("");
   const [composeReferences, setComposeReferences] = useState("");
   const [composeSending, setComposeSending] = useState(false);
+  const [pendingDeleteMail, setPendingDeleteMail] = useState<ReceivedMail | null>(null);
+  const [pendingDeleteAccount, setPendingDeleteAccount] = useState<UserMailAccount | null>(null);
+  const [showPassword, setShowPassword] = useState(false);
 
   const detailCacheRef = useRef<Map<string, MailDetail>>(new Map());
   const prefetchingRef = useRef<Set<string>>(new Set());
@@ -321,7 +337,13 @@ export default function ImapMailPage() {
 
   async function handleDeleteMail(mail: ReceivedMail) {
     if (!selectedAccount) return;
-    if (!confirm("메일을 삭제하시겠습니까?")) return;
+    setPendingDeleteMail(mail);
+  }
+
+  async function confirmDeleteMail() {
+    if (!selectedAccount || !pendingDeleteMail) return;
+    const mail = pendingDeleteMail;
+    setPendingDeleteMail(null);
     const seqno = parseInt(mail.id.split("-").pop() || "0");
     try {
       await deleteUserMail(selectedAccount.id, seqno);
@@ -334,7 +356,7 @@ export default function ImapMailPage() {
       if (selectedMail?.id === mail.id) setSelectedMail(null);
       loadFolders(selectedAccount);
     } catch (e: any) {
-      alert("메일 삭제 실패: " + e.message);
+      toast.error("메일 삭제 실패: " + e.message);
     }
   }
 
@@ -393,6 +415,7 @@ export default function ImapMailPage() {
     setEditingAccount(null);
     setForm(DEFAULT_FORM);
     setTestResult(null);
+    setShowPassword(false);
     setShowDialog(true);
   }
 
@@ -409,6 +432,7 @@ export default function ImapMailPage() {
       password: "",
     });
     setTestResult(null);
+    setShowPassword(false);
     setShowDialog(true);
   }
 
@@ -440,7 +464,13 @@ export default function ImapMailPage() {
   }
 
   async function handleDeleteAccount(account: UserMailAccount) {
-    if (!confirm(`"${account.displayName}" 계정을 삭제하시겠습니까?`)) return;
+    setPendingDeleteAccount(account);
+  }
+
+  async function confirmDeleteAccount() {
+    if (!pendingDeleteAccount) return;
+    const account = pendingDeleteAccount;
+    setPendingDeleteAccount(null);
     try {
       await deleteUserMailAccount(account.id);
       if (selectedAccount?.id === account.id) {
@@ -511,10 +541,6 @@ export default function ImapMailPage() {
             <Plus className="h-4 w-4 mr-1" />
             작성
           </Button>
-          <Button size="sm" onClick={openAddDialog}>
-            <Plus className="h-4 w-4 mr-1" />
-            계정 추가
-          </Button>
         </div>
       </div>
 
@@ -527,7 +553,14 @@ export default function ImapMailPage() {
               <div className="px-3 py-2 border-b text-xs font-medium text-muted-foreground flex items-center gap-1">
                 <Inbox className="h-3.5 w-3.5" />
                 계정 목록
-                {loadingAccounts && <Loader2 className="h-3 w-3 animate-spin ml-auto" />}
+                {loadingAccounts && <Loader2 className="h-3 w-3 animate-spin" />}
+                <button
+                  className="ml-auto p-0.5 hover:text-foreground text-muted-foreground"
+                  onClick={openAddDialog}
+                  title="계정 추가"
+                >
+                  <Plus className="h-3.5 w-3.5" />
+                </button>
               </div>
               <div className="flex-1 overflow-y-auto">
                 {imapAccounts.length === 0 && !loadingAccounts ? (
@@ -633,7 +666,7 @@ export default function ImapMailPage() {
                 ) : filteredMails.length === 0 ? (
                   <div className="flex flex-col items-center justify-center h-full text-muted-foreground gap-2">
                     <Inbox className="h-8 w-8 opacity-30" />
-                    <p className="text-sm">메일이 없습니다</p>
+                    <p className="text-sm">{searchTerm ? `"${searchTerm}" 검색 결과가 없습니다` : "메일이 없습니다"}</p>
                   </div>
                 ) : (
                   <>
@@ -756,13 +789,13 @@ export default function ImapMailPage() {
                                 try {
                                   const list = await getUserMailAttachments(accountId, seqno, currentFolder);
                                   const matched = list.find(a => a.filename === att.filename) || list[i];
-                                  if (!matched) { alert('첨부파일 정보를 불러올 수 없습니다'); return; }
+                                  if (!matched) { toast.error('첨부파일 정보를 불러올 수 없습니다'); return; }
                                   await downloadAttachment(
                                     accountId, seqno, matched.partId, matched.filename, currentFolder,
                                     (pct) => setDownloadProgress(p => ({ ...p, [i]: pct })),
                                     matched.size
                                   );
-                                } catch (e: any) { alert(e.message); }
+                                } catch (e: any) { toast.error(e.message); }
                                 finally { setDownloadProgress(p => { const next = { ...p }; delete next[i]; return next; }); }
                               }}
                               className="relative inline-flex items-center gap-1 text-xs px-2 py-0.5 rounded-full bg-secondary hover:bg-accent border disabled:opacity-60 disabled:cursor-not-allowed cursor-pointer min-w-[80px] overflow-hidden">
@@ -873,7 +906,7 @@ export default function ImapMailPage() {
               <Input
                 type="email"
                 value={form.email}
-                onChange={(e) => setForm((p) => ({ ...p, email: e.target.value }))}
+                onChange={(e) => setForm((p) => ({ ...p, email: e.target.value, username: e.target.value }))}
                 placeholder="user@example.com"
               />
             </div>
@@ -909,12 +942,22 @@ export default function ImapMailPage() {
             </div>
             <div className="space-y-1">
               <Label className="text-xs">비밀번호 {editingAccount && "(변경 시에만 입력)"}</Label>
-              <Input
-                type="password"
-                value={form.password}
-                onChange={(e) => setForm((p) => ({ ...p, password: e.target.value }))}
-                placeholder="••••••••"
-              />
+              <div className="relative">
+                <Input
+                  type={showPassword ? "text" : "password"}
+                  value={form.password}
+                  onChange={(e) => setForm((p) => ({ ...p, password: e.target.value }))}
+                  placeholder="••••••••"
+                  className="pr-9"
+                />
+                <button
+                  type="button"
+                  className="absolute right-2 top-1/2 -translate-y-1/2 text-muted-foreground hover:text-foreground"
+                  onClick={() => setShowPassword((v) => !v)}
+                >
+                  {showPassword ? <EyeOff className="h-4 w-4" /> : <Eye className="h-4 w-4" />}
+                </button>
+              </div>
             </div>
             {editingAccount && (
               <div>
@@ -958,6 +1001,34 @@ export default function ImapMailPage() {
           </DialogFooter>
         </DialogContent>
       </Dialog>
+
+      {/* 메일 삭제 확인 */}
+      <AlertDialog open={!!pendingDeleteMail} onOpenChange={(open) => { if (!open) setPendingDeleteMail(null); }}>
+        <AlertDialogContent>
+          <AlertDialogHeader>
+            <AlertDialogTitle>메일 삭제</AlertDialogTitle>
+            <AlertDialogDescription>메일을 삭제하시겠습니까?</AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel>취소</AlertDialogCancel>
+            <AlertDialogAction onClick={confirmDeleteMail} className="bg-destructive text-destructive-foreground hover:bg-destructive/90">삭제</AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
+
+      {/* 계정 삭제 확인 */}
+      <AlertDialog open={!!pendingDeleteAccount} onOpenChange={(open) => { if (!open) setPendingDeleteAccount(null); }}>
+        <AlertDialogContent>
+          <AlertDialogHeader>
+            <AlertDialogTitle>계정 삭제</AlertDialogTitle>
+            <AlertDialogDescription>"{pendingDeleteAccount?.displayName}" 계정을 삭제하시겠습니까?</AlertDialogDescription>
+          </AlertDialogHeader>
+          <AlertDialogFooter>
+            <AlertDialogCancel>취소</AlertDialogCancel>
+            <AlertDialogAction onClick={confirmDeleteAccount} className="bg-destructive text-destructive-foreground hover:bg-destructive/90">삭제</AlertDialogAction>
+          </AlertDialogFooter>
+        </AlertDialogContent>
+      </AlertDialog>
     </div>
   );
 }