feat: 모바일 대응 + 삭제 모드 UI 개선

- 모바일: 헤더에 + 등록 버튼, 삭제는 아이콘 버튼
- 삭제 모드: 탭 아래 바에 전체선택/삭제/취소 배치
- 체크박스 CSS transition 애니메이션
- 100dvh 적용 (모바일 브라우저 대응)
- 최소 너비 320px 설정
- 운송장 번호 공백/하이픈 자동 제거
- 날짜에 요일 표시

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/App.jsx

@@ -1,23 +1,32 @@
+import { useState } from "react";
+import { Plus } from "lucide-react";
 import MainPage from "@/pages/MainPage";
 import Toast from "@/components/Toast";
 import useToastStore from "@/stores/useToastStore";
 
 function App() {
   const toastMessage = useToastStore((s) => s.message);
+  const [showForm, setShowForm] = useState(false);
 
   return (
-    <div className="h-screen overflow-hidden flex flex-col bg-secondary">
+    <div className="h-[100dvh] min-w-[320px] overflow-hidden flex flex-col bg-secondary">
       <header className="flex-shrink-0 bg-white border-b border-gray-200 z-10">
         <div className="max-w-2xl lg:max-w-4xl mx-auto px-4 py-3 lg:py-4 flex items-center gap-2">
           <a href="/" className="flex items-center gap-2 no-underline">
             <span className="text-xl lg:text-2xl font-bold text-primary">Traeon</span>
             <span className="text-sm lg:text-base text-gray-400">택배 배송조회</span>
           </a>
+          <button
+            onClick={() => setShowForm(!showForm)}
+            className="ml-auto lg:hidden text-primary hover:text-primary-dark p-1.5"
+          >
+            <Plus size={22} />
+          </button>
         </div>
       </header>
       <main className="flex-1 min-h-0 overflow-hidden">
         <div className="h-full max-w-2xl lg:max-w-4xl mx-auto px-4 py-6 lg:py-8 flex flex-col">
-          <MainPage />
+          <MainPage showForm={showForm} setShowForm={setShowForm} />
         </div>
       </main>
       <Toast message={toastMessage} />

frontend/src/pages/MainPage.jsx

@@ -13,8 +13,7 @@ import { Loader2, Package, Trash2 } from "lucide-react";
 
 const PAGE_LIMIT = 20;
 
-function MainPage() {
-  const [showForm, setShowForm] = useState(false);
+function MainPage({ showForm, setShowForm }) {
   const [selectedId, setSelectedId] = useState(null);
   const [deleteMode, setDeleteMode] = useState(false);
   const [checkedIds, setCheckedIds] = useState(new Set());
@@ -122,56 +121,91 @@ function MainPage() {
 
   return (
     <div className="flex flex-col h-full min-h-0">
-      <div className="flex-shrink-0 flex items-center justify-between mb-4">
-        <FilterTabs
-          filter={filter}
-          onFilterChange={handleFilterChange}
-          activeCount={activeCount}
-          deliveredCount={deliveredCount}
-          totalCount={allCount}
-        />
-        <div className="flex items-center gap-2">
-          {deleteMode ? (
-            <>
-              <button
-                onClick={toggleAll}
-                className="px-3 lg:px-4 py-2 lg:py-2.5 text-sm lg:text-base text-gray-500 hover:text-gray-700 transition-colors"
-              >
-                {checkedIds.size === parcels.length ? "선택해제" : "전체선택"}
-              </button>
-              <button
-                onClick={() => checkedIds.size > 0 && setShowDeleteConfirm(true)}
-                disabled={checkedIds.size === 0}
-                className="px-4 lg:px-5 py-2 lg:py-2.5 bg-red-500 text-white rounded-lg text-sm lg:text-base font-medium hover:bg-red-600 transition-colors disabled:opacity-40"
-              >
-                삭제 ({checkedIds.size})
-              </button>
-              <button
-                onClick={exitDeleteMode}
-                className="px-3 lg:px-4 py-2 lg:py-2.5 text-sm lg:text-base text-gray-500 hover:text-gray-700 transition-colors"
-              >
-                취소
-              </button>
-            </>
-          ) : (
-            <>
-              {parcels.length > 0 && (
+      <div className="flex-shrink-0 mb-4 space-y-3">
+        <div className="flex items-center justify-between">
+          <FilterTabs
+            filter={filter}
+            onFilterChange={handleFilterChange}
+            activeCount={activeCount}
+            deliveredCount={deliveredCount}
+            totalCount={allCount}
+          />
+          <div className="flex items-center gap-2 shrink-0">
+            {!deleteMode && parcels.length > 0 && (
+              <>
                 <button
                   onClick={() => setDeleteMode(true)}
-                  className="px-4 lg:px-5 py-[7px] lg:py-[9px] border border-red-300 text-red-500 rounded-lg text-sm lg:text-base font-medium hover:bg-red-50 transition-colors"
+                  className="hidden lg:block px-5 py-[9px] border border-red-300 text-red-500 rounded-lg text-base font-medium hover:bg-red-50 transition-colors"
                 >
                   삭제
                 </button>
-              )}
+                <button
+                  onClick={() => setDeleteMode(true)}
+                  className="lg:hidden p-2 text-gray-400 hover:text-red-500 transition-colors"
+                >
+                  <Trash2 size={18} />
+                </button>
+              </>
+            )}
+            {!deleteMode && (
               <button
                 onClick={() => setShowForm(!showForm)}
-                className="px-4 lg:px-5 py-2 lg:py-2.5 bg-primary text-white rounded-lg text-sm lg:text-base font-medium hover:bg-primary-dark transition-colors"
+                className="hidden lg:block px-5 py-2.5 bg-primary text-white rounded-lg text-base font-medium hover:bg-primary-dark transition-colors"
               >
                 {showForm ? "취소" : "+ 등록"}
               </button>
-            </>
-          )}
+            )}
+          </div>
         </div>
+
+        <AnimatePresence>
+          {deleteMode && (
+            <motion.div
+              initial={{ opacity: 0, height: 0 }}
+              animate={{ opacity: 1, height: "auto" }}
+              exit={{ opacity: 0, height: 0 }}
+              transition={{ duration: 0.2 }}
+              className="overflow-hidden"
+            >
+              <div className="flex items-center justify-between bg-red-50 rounded-lg px-3 lg:px-4 py-2.5 lg:py-3">
+                <button
+                  onClick={toggleAll}
+                  className="flex items-center gap-2 text-xs lg:text-sm text-gray-600"
+                >
+                  <div
+                    className={`w-4 h-4 lg:w-[18px] lg:h-[18px] rounded border-2 flex items-center justify-center transition-all ${
+                      checkedIds.size === parcels.length && parcels.length > 0
+                        ? "bg-red-500 border-red-500"
+                        : "border-gray-300"
+                    }`}
+                  >
+                    {checkedIds.size === parcels.length && parcels.length > 0 && (
+                      <svg viewBox="0 0 12 12" className="w-2.5 h-2.5 text-white" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+                        <path d="M2 6l3 3 5-5" />
+                      </svg>
+                    )}
+                  </div>
+                  전체선택 ({checkedIds.size}/{parcels.length})
+                </button>
+                <div className="flex items-center gap-2">
+                  <button
+                    onClick={exitDeleteMode}
+                    className="px-3 lg:px-4 py-1.5 text-xs lg:text-sm text-gray-500 hover:text-gray-700 rounded-lg transition-colors"
+                  >
+                    취소
+                  </button>
+                  <button
+                    onClick={() => checkedIds.size > 0 && setShowDeleteConfirm(true)}
+                    disabled={checkedIds.size === 0}
+                    className="px-3.5 lg:px-4 py-2 lg:py-2 bg-red-500 text-white rounded-lg text-xs lg:text-sm font-medium hover:bg-red-600 transition-colors disabled:opacity-40"
+                  >
+                    삭제 ({checkedIds.size})
+                  </button>
+                </div>
+              </div>
+            </motion.div>
+          )}
+        </AnimatePresence>
       </div>
 
       <AnimatePresence>
@@ -222,31 +256,30 @@ function MainPage() {
                   }}
                 >
                   <div className="flex items-center gap-2">
-                    {deleteMode && (
-                      <motion.div
-                        initial={{ opacity: 0, width: 0 }}
-                        animate={{ opacity: 1, width: "auto" }}
-                        className="shrink-0"
-                      >
-                        <div
-                          onClick={(e) => {
-                            e.stopPropagation();
-                            toggleCheck(parcel.id);
-                          }}
-                          className={`w-5 h-5 rounded-md border-2 flex items-center justify-center cursor-pointer transition-all ${
-                            checkedIds.has(parcel.id)
-                              ? "bg-primary border-primary"
-                              : "border-gray-300 hover:border-primary/50"
-                          }`}
-                        >
-                          {checkedIds.has(parcel.id) && (
-                            <svg viewBox="0 0 12 12" className="w-3 h-3 text-white" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
-                              <path d="M2 6l3 3 5-5" />
-                            </svg>
-                          )}
-                        </div>
-                      </motion.div>
-                    )}
+                    <div
+                      onClick={(e) => {
+                        if (!deleteMode) return;
+                        e.stopPropagation();
+                        toggleCheck(parcel.id);
+                      }}
+                      className={`w-5 h-5 rounded-md border-2 flex items-center justify-center shrink-0 transition-all duration-300 ${
+                        deleteMode
+                          ? "opacity-100 scale-100 mr-0"
+                          : "opacity-0 scale-0 w-0 -mr-2"
+                      } ${
+                        deleteMode && checkedIds.has(parcel.id)
+                          ? "bg-primary border-primary cursor-pointer"
+                          : deleteMode
+                            ? "border-gray-300 hover:border-primary/50 cursor-pointer"
+                            : "border-transparent"
+                      }`}
+                    >
+                      {checkedIds.has(parcel.id) && deleteMode && (
+                        <svg viewBox="0 0 12 12" className="w-3 h-3 text-white" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round" strokeLinejoin="round">
+                          <path d="M2 6l3 3 5-5" />
+                        </svg>
+                      )}
+                    </div>
                     <div className="flex-1 min-w-0">
                       <ParcelCard
                         parcel={parcel}