diff --git a/app/modules/cupang/router.py b/app/modules/cupang/router.py
index 38cf4da..58d52b1 100644
--- a/app/modules/cupang/router.py
+++ b/app/modules/cupang/router.py
@@ -592,6 +592,7 @@ async def box_calc_page(request: Request) -> HTMLResponse:
             "page_title": "쿠팡 밀크런 — 박스 계산",
             "page_subtitle": "제품명과 수량을 넣으면 박스 수와 남은 낱개를 계산합니다.",
             "box_rules": store.list_box_rules(),
+            "centers": store.list_centers(),
         },
     )
 
diff --git a/app/modules/cupang/templates/cupang/box_calc.html b/app/modules/cupang/templates/cupang/box_calc.html
index ab83b4c..32e2075 100644
--- a/app/modules/cupang/templates/cupang/box_calc.html
+++ b/app/modules/cupang/templates/cupang/box_calc.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
@@ -8,6 +8,7 @@
   <div class="erp-page-actions">
     <a class="erp-btn erp-btn-primary" href="/cupang/">◀◀ 달력</a>
     <a class="erp-btn erp-btn-outline" href="/cupang/box-rules">박스 입수량 설정</a>
+    <a class="erp-btn erp-btn-outline" href="/cupang/centers">입고센터 관리</a>
   </div>
 
   {% if not box_rules %}
@@ -19,69 +20,99 @@
   </div>
   {% else %}
 
-  <div class="cpg-calc-layout">
+  <div class="cpg-calc3">
 
-  <div class="erp-card cpg-form-card cpg-calc-card">
-    <div class="cpg-card-head">
-      <h2>박스 계산</h2>
-      <span class="erp-muted">수량을 고치고 다시 계산하면 결과가 갱신됩니다.</span>
+    <!-- ① 박스 계산 — 제품명 + 수량만 입력 -->
+    <div class="erp-card cpg-form-card cpg-calc-card">
+      <div class="cpg-card-head">
+        <h2>① 박스 계산</h2>
+        <span class="erp-muted">수량 칸에서 Tab = 다음 상품 수량, Enter = 계산</span>
+      </div>
+
+      <div class="erp-table-wrap">
+        <table class="erp-table cpg-calc-table">
+          <colgroup>
+            <col class="cpg-col-name" />
+            <col class="cpg-col-qty" />
+            <col class="cpg-col-act" />
+          </colgroup>
+          <thead>
+            <tr>
+              <th>제품명</th>
+              <th>수량</th>
+              <th></th>
+            </tr>
+          </thead>
+          <tbody id="cpg-calc-rows"></tbody>
+        </table>
+      </div>
+
+      <div class="erp-page-actions cpg-calc-actions">
+        <button type="button" class="erp-btn erp-btn-primary" id="cpg-calc-run">계산 / 재계산</button>
+        <button type="button" class="erp-btn erp-btn-outline" id="cpg-calc-add">+ 제품 추가</button>
+        <button type="button" class="erp-btn erp-btn-outline" id="cpg-calc-reset">초기화</button>
+        <span class="erp-muted" id="cpg-calc-msg"></span>
+      </div>
     </div>
 
-    <div class="erp-table-wrap">
-      <table class="erp-table cpg-calc-table">
-        <colgroup>
-          <col class="cpg-col-name" />
-          <col class="cpg-col-qty" />
-          <col class="cpg-col-box" />
-          <col class="cpg-col-n" />
-          <col class="cpg-col-n" />
-          <col class="cpg-col-n" />
-          <col class="cpg-col-act" />
-        </colgroup>
-        <thead>
-          <tr>
-            <th>제품명</th>
-            <th class="cpg-calc-num">수량</th>
-            <th>박스 / 입수량</th>
-            <th class="cpg-calc-num">박스</th>
-            <th class="cpg-calc-num">낱개</th>
-            <th class="cpg-calc-num">필요</th>
-            <th></th>
-          </tr>
-        </thead>
-        <tbody id="cpg-calc-rows"></tbody>
-      </table>
+    <!-- ② 박스 요약 — 센터에 배분하고 남은 수량이 실시간 반영 -->
+    <div class="erp-card cpg-form-card cpg-calc-sum">
+      <div class="cpg-card-head">
+        <h2>② 박스 요약</h2>
+        <span class="erp-muted">카드를 ③ 센터로 끌어다 놓으면 잔여가 줄어듭니다.</span>
+      </div>
+
+      <div id="cpg-sum-empty" class="erp-muted">왼쪽에서 제품과 수량을 넣고 계산하세요.</div>
+
+      <div id="cpg-sum-body" hidden>
+        <div class="cpg-sum-kpis" id="cpg-sum-kpis"></div>
+
+        <h3 class="cpg-sum-h3">제품별 박스 <span class="erp-muted">잔여 기준</span></h3>
+        <div class="cpg-sum-prods" id="cpg-sum-prods"></div>
+
+        <h3 class="cpg-sum-h3">자투리 혼합 박스 <span class="erp-muted" id="cpg-sum-mix-note"></span></h3>
+        <div class="cpg-sum-boxes" id="cpg-sum-boxes"></div>
+      </div>
     </div>
 
-    <div class="erp-page-actions cpg-calc-actions">
-      <button type="button" class="erp-btn erp-btn-primary" id="cpg-calc-run">계산 / 재계산</button>
-      <button type="button" class="erp-btn erp-btn-outline" id="cpg-calc-add">+ 제품 추가</button>
-      <button type="button" class="erp-btn erp-btn-outline" id="cpg-calc-reset">초기화</button>
-      <span class="erp-muted" id="cpg-calc-msg"></span>
-    </div>
-  </div>
+    <!-- ③ 센터 분배 — 드래그해서 담고 수량 입력 -->
+    <div class="erp-card cpg-form-card cpg-dist-card">
+      <div class="cpg-card-head">
+        <h2>③ 센터 분배</h2>
+        <span class="erp-muted">입고센터 관리에 등록한 센터만 표시됩니다.</span>
+      </div>
 
-  <div class="erp-card cpg-form-card cpg-calc-sum" id="cpg-calc-sum-card" hidden>
-    <div class="cpg-card-head">
-      <h2>박스 요약</h2>
-      <span class="erp-muted">제품별 박스 + 자투리를 모아 담은 혼합 박스</span>
+      {% if not centers %}
+      <p class="erp-muted">
+        등록된 입고센터가 없습니다. <a href="/cupang/centers">입고센터 관리</a>에서 먼저 센터를 추가하세요.
+      </p>
+      {% else %}
+      <div class="cpg-dist-list" id="cpg-dist-list">
+        {% for c in centers %}
+        <div class="cpg-dist-center" data-center-id="{{ c.id }}" data-center-name="{{ c.name }}">
+          <div class="cpg-dist-head">
+            <strong>{{ c.name }}</strong>
+            <span class="erp-badge erp-badge-neutral cpg-dist-total" data-total-for="{{ c.id }}">0박스</span>
+          </div>
+          <div class="cpg-dist-drop" data-drop-for="{{ c.id }}">
+            <span class="cpg-dist-hint">여기로 박스를 끌어다 놓기</span>
+            <ul class="cpg-dist-items" data-items-for="{{ c.id }}"></ul>
+          </div>
+        </div>
+        {% endfor %}
+      </div>
+      {% endif %}
     </div>
 
-    <div class="cpg-sum-kpis" id="cpg-sum-kpis"></div>
-
-    <h3 class="cpg-sum-h3">제품별 박스</h3>
-    <div class="cpg-sum-prods" id="cpg-sum-prods"></div>
-
-    <h3 class="cpg-sum-h3">자투리 혼합 박스 <span class="erp-muted" id="cpg-sum-mix-note"></span></h3>
-    <div class="cpg-sum-boxes" id="cpg-sum-boxes"></div>
-  </div>
-
-  </div><!-- /cpg-calc-layout -->
+  </div><!-- /cpg-calc3 -->
 
   <script type="application/json" id="cpg-calc-rules">{{ box_rules | tojson }}</script>
   <script>
-  // 박스 계산기 — 행 추가/삭제, 수량 수정 후 재계산.
-  // 계산 자체는 서버(POST /cupang/api/box-calc, store.compute_boxes)에서 수행한다.
+  // 박스 계산 3열 화면.
+  //  ① 제품명·수량 입력 → 서버(POST /cupang/api/box-calc)에서 계산
+  //  ② 계산 결과 요약(제품별 박스 / 자투리 혼합 박스) — 드래그 소스
+  //  ③ 센터별 분배 — 드롭 대상. 배분한 수량만큼 ② 의 잔여가 줄어든다.
+  // 분배 내역은 화면 안에서만 유지된다(DB 저장 없음).
   (function () {
     var tbody = document.getElementById("cpg-calc-rows");
     if (!tbody) return;
@@ -89,144 +120,168 @@
     var addBtn = document.getElementById("cpg-calc-add");
     var resetBtn = document.getElementById("cpg-calc-reset");
     var msg = document.getElementById("cpg-calc-msg");
-    var sumCard = document.getElementById("cpg-calc-sum-card");
+    var sumEmpty = document.getElementById("cpg-sum-empty");
+    var sumBody = document.getElementById("cpg-sum-body");
     var sumKpis = document.getElementById("cpg-sum-kpis");
     var sumProds = document.getElementById("cpg-sum-prods");
     var sumBoxes = document.getElementById("cpg-sum-boxes");
     var sumMixNote = document.getElementById("cpg-sum-mix-note");
+    var distList = document.getElementById("cpg-dist-list");
 
     var rules = [];
     try { rules = JSON.parse(document.getElementById("cpg-calc-rules").textContent || "[]"); } catch (e) {}
 
-    var optionsHtml = '<option value="">— 제품명 선택 —</option>';
-    rules.forEach(function (r) {
-      var label = r.product_name_snapshot || r.product_code;
-      optionsHtml += '<option value="' + esc(r.product_code) + '">' + esc(label) + "</option>";
-    });
-
     function esc(s) { var d = document.createElement("div"); d.textContent = s == null ? "" : s; return d.innerHTML; }
 
+    var optionsHtml = '<option value="">— 제품명 선택 —</option>';
+    rules.forEach(function (r) {
+      optionsHtml += '<option value="' + esc(r.product_code) + '">' +
+                     esc(r.product_name_snapshot || r.product_code) + "</option>";
+    });
+
+    // 계산 결과 + 센터 배분 상태
+    var calc = { results: [], mixes: [] };
+    var alloc = {};   // centerId -> [{id, key, kind, label, count}]
+    var seq = 0;
+
+    // ── ① 입력 표 ─────────────────────────────────────
     function addRow(code, qty) {
       var tr = document.createElement("tr");
       tr.className = "cpg-calc-row";
       tr.innerHTML =
         '<td><select class="erp-select cpg-calc-name">' + optionsHtml + "</select></td>" +
-        '<td class="cpg-calc-num"><input class="erp-input cpg-calc-qty" type="number" min="0" step="1" value="' + (qty || 0) + '" /></td>' +
-        '<td class="cpg-calc-box">—</td>' +
-        '<td class="cpg-calc-num cpg-calc-boxes">—</td>' +
-        '<td class="cpg-calc-num cpg-calc-rem">—</td>' +
-        '<td class="cpg-calc-num cpg-calc-req">—</td>' +
+        '<td><input class="erp-input cpg-calc-qty" type="number" min="0" step="1" value="' + (qty || 0) + '" /></td>' +
         '<td class="cpg-calc-act"><button type="button" class="erp-btn erp-btn-danger cpg-calc-del" title="행 삭제" aria-label="행 삭제">✕</button></td>';
       tbody.appendChild(tr);
       if (code) tr.querySelector(".cpg-calc-name").value = code;
       return tr;
     }
 
-    function clearResults() {
-      Array.prototype.forEach.call(tbody.querySelectorAll(".cpg-calc-row"), function (tr) {
-        tr.querySelector(".cpg-calc-box").textContent = "—";
-        tr.querySelector(".cpg-calc-boxes").textContent = "—";
-        tr.querySelector(".cpg-calc-rem").textContent = "—";
-        tr.querySelector(".cpg-calc-req").textContent = "—";
-        tr.classList.remove("cpg-calc-warn");
-      });
-      sumCard.hidden = true;
-      sumKpis.innerHTML = "";
-      sumProds.innerHTML = "";
-      sumBoxes.innerHTML = "";
-      sumMixNote.textContent = "";
+    function rowsArr() {
+      return Array.prototype.slice.call(tbody.querySelectorAll(".cpg-calc-row"));
     }
 
     function collect() {
       var items = [];
-      Array.prototype.forEach.call(tbody.querySelectorAll(".cpg-calc-row"), function (tr) {
+      rowsArr().forEach(function (tr) {
         var code = tr.querySelector(".cpg-calc-name").value;
         if (!code) return;
-        items.push({ product_code: code, quantity: parseInt(tr.querySelector(".cpg-calc-qty").value, 10) || 0, _tr: tr });
+        items.push({ product_code: code, quantity: parseInt(tr.querySelector(".cpg-calc-qty").value, 10) || 0 });
       });
       return items;
     }
 
     function run() {
       var items = collect();
-      if (!items.length) { clearResults(); msg.textContent = "제품명을 하나 이상 선택하세요."; return; }
+      if (!items.length) { msg.textContent = "제품명을 하나 이상 선택하세요."; return; }
       msg.textContent = "계산 중…";
       runBtn.disabled = true;
       fetch("/cupang/api/box-calc", {
         method: "POST",
         headers: { "Content-Type": "application/json" },
-        body: JSON.stringify({ items: items.map(function (it) { return { product_code: it.product_code, quantity: it.quantity }; }) })
+        body: JSON.stringify({ items: items })
       })
         .then(function (r) { if (!r.ok) throw new Error("http " + r.status); return r.json(); })
         .then(function (data) {
-          var results = (data && data.results) || [];
-          results.forEach(function (res, i) {
-            var tr = items[i] && items[i]._tr;
-            if (!tr) return;
-            tr.querySelector(".cpg-calc-box").textContent = res.units_per_box
-              ? (res.box_name || "-") + " · " + res.units_per_box + "개"
-              : "미설정";
-            if (res.configured) {
-              tr.querySelector(".cpg-calc-boxes").textContent = res.full_boxes;
-              tr.querySelector(".cpg-calc-rem").textContent = res.remainder_units;
-              tr.querySelector(".cpg-calc-req").textContent = res.required_boxes;
-              tr.classList.remove("cpg-calc-warn");
-            } else {
-              tr.querySelector(".cpg-calc-boxes").textContent = "—";
-              tr.querySelector(".cpg-calc-rem").textContent = "—";
-              tr.querySelector(".cpg-calc-req").textContent = "—";
-              tr.classList.add("cpg-calc-warn");
-            }
-          });
-          renderSummary(results, (data && data.mixes) || [], (data && data.grand_total_boxes) || 0);
-          msg.textContent = "계산 완료 (" + results.length + "건)";
+          calc.results = ((data && data.results) || []).filter(function (r) { return r.configured; });
+          calc.mixes = (data && data.mixes) || [];
+          var had = Object.keys(alloc).some(function (k) { return alloc[k].length; });
+          alloc = {};   // 계산이 바뀌면 이전 배분은 근거가 사라지므로 비운다.
+          render();
+          msg.textContent = "계산 완료 (" + calc.results.length + "건)" + (had ? " — 센터 분배 초기화됨" : "");
         })
         .catch(function () { msg.textContent = "계산 실패 — 새로고침 후 다시 시도하세요."; })
         .then(function () { runBtn.disabled = false; });
     }
 
-    // ── 요약 렌더 ─────────────────────────────────────────
-    // 상자 그림: fill(0~100) 만큼 안쪽이 차오르고, 뚜껑이 살짝 열린 채 표시.
+    // ── 배분 집계 ─────────────────────────────────────
+    function allocatedFor(key) {
+      var n = 0;
+      Object.keys(alloc).forEach(function (cid) {
+        alloc[cid].forEach(function (a) { if (a.key === key) n += a.count; });
+      });
+      return n;
+    }
+
+    function mixKey(boxName, idx) { return "m:" + boxName + "#" + idx; }
+    function prodKey(code) { return "p:" + code; }
+
+    function totalFor(key) {
+      if (key.indexOf("p:") === 0) {
+        var code = key.slice(2);
+        var hit = calc.results.filter(function (r) { return r.product_code === code; })[0];
+        return hit ? hit.full_boxes : 0;
+      }
+      return 1;   // 혼합 박스는 1장 = 1박스
+    }
+
+    function remainFor(key) { return Math.max(0, totalFor(key) - allocatedFor(key)); }
+
+    // ── ② 요약 렌더 ───────────────────────────────────
     function boxSvg(fill, label) {
       var f = Math.max(0, Math.min(100, fill || 0));
       var h = 40 * f / 100;
       return '' +
-        '<svg class="cpg-box-svg" viewBox="0 0 72 64" role="img" aria-label="' + esc(label) + ' 박스">' +
+        '<svg class="cpg-box-svg" viewBox="0 0 72 64" role="img" aria-label="' + esc(label) + '">' +
           '<rect class="cpg-box-fill" x="10" y="' + (54 - h) + '" width="52" height="' + h + '" rx="2" />' +
           '<path class="cpg-box-body" d="M10 20 H62 V54 H10 Z" />' +
           '<path class="cpg-box-flapL" d="M10 20 L2 8 H30 L36 20 Z" />' +
           '<path class="cpg-box-flapR" d="M62 20 L70 8 H42 L36 20 Z" />' +
           '<line class="cpg-box-seam" x1="36" y1="20" x2="36" y2="54" />' +
-          '<text class="cpg-box-label" x="36" y="42" text-anchor="middle">' + esc(label) + "</text>" +
+          '<text class="cpg-box-label" x="36" y="42" text-anchor="middle">쿠팡박스</text>' +
         "</svg>";
     }
 
+    function kpi(label, value, hint) {
+      return '<div class="cpg-kpi"><span class="cpg-kpi-label">' + esc(label) + "</span>" +
+             '<strong class="cpg-kpi-value">' + esc(value) + "</strong>" +
+             '<span class="cpg-kpi-hint">' + esc(hint) + "</span></div>";
+    }
 
+    function renderSummary() {
+      if (!calc.results.length) {
+        sumEmpty.hidden = false;
+        sumBody.hidden = true;
+        return;
+      }
+      sumEmpty.hidden = true;
+      sumBody.hidden = false;
 
-    function renderSummary(results, mixes, grandTotal) {
-      var ok = results.filter(function (r) { return r.configured; });
-      if (!ok.length) { sumCard.hidden = true; return; }
-
-      var fullSum = 0, mixSum = 0, leftoverSum = 0;
-      ok.forEach(function (r) { fullSum += r.full_boxes; leftoverSum += r.remainder_units; });
-      mixes.forEach(function (m) { mixSum += m.box_count; });
+      var totalProd = 0, remainProd = 0, leftoverUnits = 0;
+      calc.results.forEach(function (r) {
+        totalProd += r.full_boxes;
+        remainProd += remainFor(prodKey(r.product_code));
+        leftoverUnits += r.remainder_units;
+      });
+      var totalMix = 0, remainMix = 0;
+      calc.mixes.forEach(function (m) {
+        m.boxes.forEach(function (b, i) {
+          totalMix += 1;
+          remainMix += remainFor(mixKey(m.box_name, i));
+        });
+      });
+      var assigned = (totalProd + totalMix) - (remainProd + remainMix);
 
       sumKpis.innerHTML =
-        kpi("총 박스", (grandTotal || (fullSum + mixSum)) + "박스", "제품별 박스 + 혼합 박스") +
-        kpi("제품별 박스", fullSum + "박스", "한 제품만 가득 채운 박스") +
-        kpi("혼합 박스", mixSum + "박스", "자투리 " + leftoverSum + "개를 모아 담음");
+        kpi("총 박스", (totalProd + totalMix) + "박스", "제품별 " + totalProd + " + 혼합 " + totalMix) +
+        kpi("센터 배분", assigned + "박스", "③ 에 담긴 수량") +
+        kpi("미배분 잔여", (remainProd + remainMix) + "박스", "자투리 " + leftoverUnits + "개 포함");
 
-      // 제품별
       var ph = "";
-      ok.forEach(function (r) {
-        ph += '<div class="cpg-sum-prod">' +
+      calc.results.forEach(function (r) {
+        var key = prodKey(r.product_code);
+        var remain = remainFor(key);
+        var used = r.full_boxes - remain;
+        ph += '<div class="cpg-sum-prod' + (remain ? "" : " is-done") + '"' +
+                (remain ? ' draggable="true"' : "") +
+                ' data-key="' + esc(key) + '" data-kind="product" data-label="' + esc(r.product_name) + '">' +
                 '<div class="cpg-sum-prod-head">' +
                   '<span class="cpg-sum-prod-name">' + esc(r.product_name) + "</span>" +
                   '<span class="erp-badge erp-badge-neutral">' + esc(r.box_name) + "</span>" +
                 "</div>" +
                 '<div class="cpg-sum-prod-nums">' +
-                  '<strong>' + r.full_boxes + "박스</strong>" +
-                  '<span class="erp-muted">' + r.quantity + "개 ÷ " + r.units_per_box + "개</span>" +
+                  "<strong>" + remain + "박스</strong>" +
+                  '<span class="erp-muted">총 ' + r.full_boxes + "박스" + (used ? " · 배분 " + used : "") + "</span>" +
                   (r.remainder_units
                     ? '<span class="cpg-sum-left">자투리 ' + r.remainder_units + "개</span>"
                     : '<span class="cpg-sum-exact">딱 맞음</span>') +
@@ -235,22 +290,28 @@
       });
       sumProds.innerHTML = ph;
 
-      // 자투리 혼합 박스
-      if (!mixes.length) {
+      if (!calc.mixes.length) {
         sumMixNote.textContent = "— 자투리 없음";
-        sumBoxes.innerHTML = '<p class="erp-muted">남는 낱개가 없습니다. 모든 박스가 딱 맞습니다.</p>';
+        sumBoxes.innerHTML = '<p class="erp-muted">남는 낱개가 없습니다.</p>';
       } else {
-        sumMixNote.textContent = "— 같은 박스명끼리만 섞습니다";
+        sumMixNote.textContent = "— 1장 = 1박스";
         var bh = "", n = 0;
-        mixes.forEach(function (m) {
+        calc.mixes.forEach(function (m) {
           m.boxes.forEach(function (b, i) {
+            var key = mixKey(m.box_name, i);
+            var remain = remainFor(key);
             var items = b.items.map(function (it) {
-              return '<li><span>' + esc(it.product_name) + "</span><b>" + it.quantity + "개</b></li>";
+              return "<li><span>" + esc(it.product_name) + "</span><b>" + it.quantity + "개</b></li>";
             }).join("");
-            bh += '<div class="cpg-box-card" style="animation-delay:' + (n * 70) + 'ms">' +
-                    '<div class="cpg-box-art">' + boxSvg(b.fill_percent, "쿠팡박스") + "</div>" +
+            bh += '<div class="cpg-box-card' + (remain ? "" : " is-done") + '"' +
+                    (remain ? ' draggable="true"' : "") +
+                    ' data-key="' + esc(key) + '" data-kind="mix"' +
+                    ' data-label="' + esc(m.box_name + " 혼합 #" + (i + 1)) + '"' +
+                    ' style="animation-delay:' + (n * 60) + 'ms">' +
+                    '<div class="cpg-box-art">' + boxSvg(b.fill_percent, m.box_name) + "</div>" +
                     '<div class="cpg-box-info">' +
-                      '<div class="cpg-box-title">' + esc(m.box_name) + " 혼합 #" + (i + 1) + "</div>" +
+                      '<div class="cpg-box-title">' + esc(m.box_name) + " 혼합 #" + (i + 1) +
+                        (remain ? "" : ' <span class="erp-badge erp-badge-success">배분됨</span>') + "</div>" +
                       '<ul class="cpg-box-items">' + items + "</ul>" +
                       '<div class="cpg-box-bar"><span style="width:' + b.fill_percent + '%"></span></div>' +
                       '<div class="cpg-box-fillnum">' + b.fill_percent + "% 채움</div>" +
@@ -261,45 +322,159 @@
         });
         sumBoxes.innerHTML = bh;
       }
-      sumCard.hidden = false;
     }
 
-    function kpi(label, value, hint) {
-      return '<div class="cpg-kpi"><span class="cpg-kpi-label">' + esc(label) + "</span>" +
-             '<strong class="cpg-kpi-value">' + esc(value) + "</strong>" +
-             '<span class="cpg-kpi-hint">' + esc(hint) + "</span></div>";
+    // ── ③ 센터 분배 렌더 ──────────────────────────────
+    function renderDist() {
+      if (!distList) return;
+      Array.prototype.forEach.call(distList.querySelectorAll(".cpg-dist-center"), function (box) {
+        var cid = box.getAttribute("data-center-id");
+        var list = box.querySelector("[data-items-for]");
+        var totalEl = box.querySelector("[data-total-for]");
+        var rows = alloc[cid] || [];
+        var total = 0;
+        var html = "";
+        rows.forEach(function (a) {
+          total += a.count;
+          var max = a.count + remainFor(a.key);
+          html += '<li class="cpg-dist-item" data-entry="' + a.id + '">' +
+                    '<span class="cpg-dist-name">' + esc(a.label) + "</span>" +
+                    '<input class="erp-input cpg-dist-qty" type="number" min="1" max="' + max + '" value="' + a.count + '" />' +
+                    '<span class="cpg-dist-unit">박스</span>' +
+                    '<button type="button" class="erp-btn erp-btn-danger cpg-dist-del" title="빼기" aria-label="빼기">✕</button>' +
+                  "</li>";
+        });
+        list.innerHTML = html;
+        box.classList.toggle("has-items", rows.length > 0);
+        totalEl.textContent = total + "박스";
+      });
     }
 
+    function render() { renderSummary(); renderDist(); }
+
+    // ── 드래그 앤 드롭 ────────────────────────────────
+    sumBody.addEventListener("dragstart", function (e) {
+      var card = e.target.closest("[data-key]");
+      if (!card || card.getAttribute("draggable") !== "true") return;
+      var payload = {
+        key: card.getAttribute("data-key"),
+        kind: card.getAttribute("data-kind"),
+        label: card.getAttribute("data-label")
+      };
+      e.dataTransfer.setData("text/plain", JSON.stringify(payload));
+      e.dataTransfer.effectAllowed = "copy";
+      card.classList.add("is-dragging");
+    });
+    sumBody.addEventListener("dragend", function (e) {
+      var card = e.target.closest("[data-key]");
+      if (card) card.classList.remove("is-dragging");
+    });
+
+    if (distList) {
+      distList.addEventListener("dragover", function (e) {
+        var zone = e.target.closest("[data-drop-for]");
+        if (!zone) return;
+        e.preventDefault();
+        e.dataTransfer.dropEffect = "copy";
+        zone.classList.add("is-over");
+      });
+      distList.addEventListener("dragleave", function (e) {
+        var zone = e.target.closest("[data-drop-for]");
+        if (zone && !zone.contains(e.relatedTarget)) zone.classList.remove("is-over");
+      });
+      distList.addEventListener("drop", function (e) {
+        var zone = e.target.closest("[data-drop-for]");
+        if (!zone) return;
+        e.preventDefault();
+        zone.classList.remove("is-over");
+        var data;
+        try { data = JSON.parse(e.dataTransfer.getData("text/plain") || "{}"); } catch (err) { return; }
+        if (!data.key) return;
+        if (remainFor(data.key) <= 0) { msg.textContent = "남은 박스가 없습니다."; return; }
+
+        var cid = zone.getAttribute("data-drop-for");
+        alloc[cid] = alloc[cid] || [];
+        var same = alloc[cid].filter(function (a) { return a.key === data.key; })[0];
+        if (same) { same.count += 1; }
+        else {
+          seq += 1;
+          alloc[cid].push({ id: seq, key: data.key, kind: data.kind, label: data.label, count: 1 });
+        }
+        render();
+      });
+
+      distList.addEventListener("input", function (e) {
+        if (!e.target.classList.contains("cpg-dist-qty")) return;
+        var li = e.target.closest(".cpg-dist-item");
+        var centerEl = e.target.closest(".cpg-dist-center");
+        var cid = centerEl.getAttribute("data-center-id");
+        var entry = (alloc[cid] || []).filter(function (a) { return String(a.id) === li.getAttribute("data-entry"); })[0];
+        if (!entry) return;
+        var want = parseInt(e.target.value, 10);
+        if (isNaN(want) || want < 1) want = 1;
+        var max = entry.count + remainFor(entry.key);
+        if (want > max) { want = max; e.target.value = max; }
+        entry.count = want;
+        // 입력 중에는 목록을 다시 그리지 않는다(포커스 유지) — 합계와 요약만 갱신.
+        var sum = 0;
+        (alloc[cid] || []).forEach(function (a) { sum += a.count; });
+        centerEl.querySelector("[data-total-for]").textContent = sum + "박스";
+        renderSummary();
+      });
+
+      distList.addEventListener("click", function (e) {
+        if (!e.target.closest(".cpg-dist-del")) return;
+        var li = e.target.closest(".cpg-dist-item");
+        var cid = e.target.closest(".cpg-dist-center").getAttribute("data-center-id");
+        alloc[cid] = (alloc[cid] || []).filter(function (a) { return String(a.id) !== li.getAttribute("data-entry"); });
+        render();
+      });
+    }
+
+    // ── 입력 표 이벤트 ────────────────────────────────
     tbody.addEventListener("click", function (e) {
-      var del = e.target.closest(".cpg-calc-del");
-      if (!del) return;
-      var rows = tbody.querySelectorAll(".cpg-calc-row");
-      if (rows.length <= 1) { addRow("", 0); }
-      del.closest("tr").remove();
+      if (!e.target.closest(".cpg-calc-del")) return;
+      if (rowsArr().length <= 1) addRow("", 0);
+      e.target.closest("tr").remove();
       msg.textContent = "";
     });
 
-    // 수량/제품을 바꾸면 이전 결과는 지운다 — 낡은 숫자 오독 방지.
     tbody.addEventListener("input", function (e) {
-      if (e.target.classList.contains("cpg-calc-qty")) { msg.textContent = "수량 변경됨 — 재계산하세요."; }
+      if (e.target.classList.contains("cpg-calc-qty")) msg.textContent = "수량 변경됨 — 재계산하세요.";
     });
     tbody.addEventListener("change", function (e) {
-      if (e.target.classList.contains("cpg-calc-name")) { msg.textContent = "제품 변경됨 — 재계산하세요."; }
+      if (e.target.classList.contains("cpg-calc-name")) msg.textContent = "제품 변경됨 — 재계산하세요.";
     });
+
+    // 수량 칸: Tab = 다음 행 수량(마지막 행이면 새 행 추가), Enter = 계산
     tbody.addEventListener("keydown", function (e) {
-      if (e.key === "Enter" && e.target.classList.contains("cpg-calc-qty")) { e.preventDefault(); run(); }
+      if (!e.target.classList.contains("cpg-calc-qty")) return;
+      if (e.key === "Enter") { e.preventDefault(); run(); return; }
+      if (e.key !== "Tab" || e.shiftKey) return;
+      e.preventDefault();
+      var rows = rowsArr();
+      var idx = rows.indexOf(e.target.closest("tr"));
+      var next = rows[idx + 1] || addRow("", 0);
+      var input = next.querySelector(".cpg-calc-qty");
+      input.focus();
+      input.select();
     });
 
     runBtn.addEventListener("click", run);
-    addBtn.addEventListener("click", function () { addRow("", 0); });
+    addBtn.addEventListener("click", function () {
+      addRow("", 0).querySelector(".cpg-calc-name").focus();
+    });
     resetBtn.addEventListener("click", function () {
       tbody.innerHTML = "";
       addRow("", 0);
-      clearResults();
+      calc = { results: [], mixes: [] };
+      alloc = {};
+      render();
       msg.textContent = "";
     });
 
     addRow("", 0);
+    render();
   })();
   </script>
   {% endif %}
diff --git a/app/modules/cupang/templates/cupang/box_rules.html b/app/modules/cupang/templates/cupang/box_rules.html
index daac23e..0c64627 100644
--- a/app/modules/cupang/templates/cupang/box_rules.html
+++ b/app/modules/cupang/templates/cupang/box_rules.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
diff --git a/app/modules/cupang/templates/cupang/centers.html b/app/modules/cupang/templates/cupang/centers.html
index 37f7ea2..dd59d6b 100644
--- a/app/modules/cupang/templates/cupang/centers.html
+++ b/app/modules/cupang/templates/cupang/centers.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
diff --git a/app/modules/cupang/templates/cupang/detail.html b/app/modules/cupang/templates/cupang/detail.html
index 7e61157..59b5803 100644
--- a/app/modules/cupang/templates/cupang/detail.html
+++ b/app/modules/cupang/templates/cupang/detail.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
diff --git a/app/modules/cupang/templates/cupang/form.html b/app/modules/cupang/templates/cupang/form.html
index 58f1adb..7eac1c4 100644
--- a/app/modules/cupang/templates/cupang/form.html
+++ b/app/modules/cupang/templates/cupang/form.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
diff --git a/app/modules/cupang/templates/cupang/index.html b/app/modules/cupang/templates/cupang/index.html
index 8aa8ca7..762ba43 100644
--- a/app/modules/cupang/templates/cupang/index.html
+++ b/app/modules/cupang/templates/cupang/index.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
diff --git a/app/modules/cupang/templates/cupang/products.html b/app/modules/cupang/templates/cupang/products.html
index 95d5154..9361385 100644
--- a/app/modules/cupang/templates/cupang/products.html
+++ b/app/modules/cupang/templates/cupang/products.html
@@ -1,6 +1,6 @@
 {% extends "erp_base.html" %}
 
-{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829a" />{% endblock %}
+{% block head_extra %}<link rel="stylesheet" href="/static/cupang.css?v=20260829b" />{% endblock %}
 
 {% block content %}
 <section class="cpg">
diff --git a/app/static/cupang.css b/app/static/cupang.css
index 8061b27..7810942 100644
--- a/app/static/cupang.css
+++ b/app/static/cupang.css
@@ -577,3 +577,75 @@
   stroke-width: 3px;
   stroke-linejoin: round;
 }
+
+/* ── 박스 계산 3열 작업 영역 (① 계산 / ② 요약 / ③ 센터 분배) ── */
+.cpg-calc3 {
+  display: grid;
+  grid-template-columns: minmax(0, 0.85fr) minmax(0, 1.25fr) minmax(0, 0.9fr);
+  gap: 16px;
+  align-items: stretch;
+}
+.cpg-calc3 > .erp-card { margin-bottom: 0; display: flex; flex-direction: column; }
+@media (max-width: 1500px) {
+  .cpg-calc3 { grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); }
+  .cpg-calc3 > .cpg-dist-card { grid-column: 1 / -1; }
+}
+@media (max-width: 1000px) {
+  .cpg-calc3 { grid-template-columns: minmax(0, 1fr); }
+  .cpg-calc3 > .cpg-dist-card { grid-column: auto; }
+}
+
+/* ② 요약: 카드가 드래그 가능함을 알린다 */
+.cpg-sum-prod[draggable="true"], .cpg-box-card[draggable="true"] { cursor: grab; }
+.cpg-sum-prod[draggable="true"]:hover, .cpg-box-card[draggable="true"]:hover {
+  border-color: var(--color-rich-black);
+}
+.cpg-sum-prod.is-dragging, .cpg-box-card.is-dragging { opacity: .45; }
+.cpg-sum-prod.is-done, .cpg-box-card.is-done { opacity: .5; }
+
+/* ③ 센터 분배 */
+.cpg-dist-list {
+  display: flex;
+  flex-direction: column;
+  gap: 10px;
+  overflow-y: auto;
+  max-height: min(72vh, 820px);
+}
+.cpg-dist-center {
+  border: 1px solid var(--color-subtle-ash);
+  border-radius: 10px;
+  padding: 10px 12px;
+}
+.cpg-dist-center.has-items { border-color: var(--color-rich-black); }
+.cpg-dist-head {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 8px;
+  margin-bottom: 8px;
+  font-size: 14px;
+}
+.cpg-dist-drop {
+  border: 1.5px dashed var(--color-subtle-ash);
+  border-radius: 8px;
+  padding: 8px;
+  min-height: 52px;
+  transition: background .15s ease, border-color .15s ease;
+}
+.cpg-dist-drop.is-over {
+  border-color: var(--color-rich-black);
+  background: var(--color-ghost-gray);
+}
+.cpg-dist-hint { font-size: 12px; color: var(--color-midtone-gray); }
+.cpg-dist-center.has-items .cpg-dist-hint { display: none; }
+.cpg-dist-items { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 6px; }
+.cpg-dist-item {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  font-size: 13px;
+}
+.cpg-dist-name { flex: 1 1 auto; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+.cpg-dist-qty { width: 62px; min-width: 0; text-align: right; padding: 2px 6px; }
+.cpg-dist-unit { font-size: 12px; color: var(--color-midtone-gray); }
+.cpg-dist-del { padding: 2px 8px; line-height: 1.4; }