Add installment calculator and Latin digits in English product text.

Wire the product CTA to store-loan-methods calculate so shoppers can pick a term and see the plan, and render English model runs under Montserrat so fanum fonts stop painting 0-9 as Persian digits.

Co-authored-by: Cursor <cursoragent@cursor.com>

AGENTS.md

@@ -327,3 +327,13 @@ identity fix, live logo/favicon wiring) once sat 3 commits ahead of
 `origin/main` unpushed, and the business reported bugs that were already
 fixed locally — they were looking at the old deployed code. Check
 `git status` for "ahead of origin" before telling anyone a fix is live.
+
+<!-- BEGIN:nextjs-agent-rules -->
+
+# This is NOT the Next.js you know
+
+This version has breaking changes — APIs, conventions, and file structure may all differ from your training data. Read the relevant guide in `node_modules/next/dist/docs/` (resolved from this file's directory; in monorepos the `next` package may not be visible from the repo root) before writing any code. Heed deprecation notices.
+
+This block is written and re-added by `next dev` — verify at `node_modules/next/dist/server/lib/generate-agent-files.js`. Removing it from a diff only re-creates the uncommitted change; committing it with your work keeps the tree clean.
+
+<!-- END:nextjs-agent-rules -->

src/app/globals.css

@@ -60,9 +60,11 @@
   padding-inline: 1rem;
 }
 
-/* Latin runs (model names, prices in EN digits) inside Farsi copy. */
+/* Latin runs (model names, SKUs) inside Farsi copy — Montserrat keeps
+   real 0-9 digits; IRANYekan fanum would otherwise paint them as ۰-۹. */
 .en {
   font-family: var(--font-en), var(--font-fa), sans-serif;
+  unicode-bidi: isolate;
 }
 
 /* Swiper theming: its own CSS reads these custom properties when drawing

src/app/products/[id]/[slug]/page.tsx

@@ -77,10 +77,11 @@ export default async function ProductDetailPage({ params }: { params: Promise<{
         ]}
       />
 
-      <div className="grid grid-cols-1 gap-8 md:gap-10 lg:grid-cols-[380px_1fr]">
+      <ProductBuyPanel
-        <ProductGallery images={images} title={title} />
+        product={product}
-        <ProductBuyPanel product={product} variants={variants} />
+        variants={variants}
-      </div>
+        gallery={<ProductGallery images={images} title={title} />}
+      />
 
       <ProductInfoTabs
         title={title}

src/app/store-items/[id]/page.tsx

@@ -91,10 +91,12 @@ export default async function StoreItemDetailPage({ params }: { params: Promise<
         ]}
       />
 
-      <div className="grid grid-cols-1 gap-8 md:gap-10 lg:grid-cols-[380px_1fr]">
+      <ProductBuyPanel
-        <ProductGallery images={images} title={title} />
+        product={product}
-        <ProductBuyPanel product={product} variants={variants} initialVariantId={variant.id} />
+        variants={variants}
-      </div>
+        initialVariantId={variant.id}
+        gallery={<ProductGallery images={images} title={title} />}
+      />
 
       <ProductInfoTabs
         title={title}

src/components/Breadcrumbs.tsx

@@ -1,4 +1,5 @@
 import Link from "next/link";
+import MixedText from "./MixedText";
 import { ChevronLeft } from "./icons";
 
 export interface Crumb {
@@ -14,10 +15,12 @@ export default function Breadcrumbs({ items }: { items: Crumb[] }) {
           {i > 0 && <ChevronLeft className="size-3.5 opacity-60" />}
           {item.href ? (
             <Link href={item.href} className="transition hover:text-brand">
-              {item.label}
+              <MixedText>{item.label}</MixedText>
             </Link>
           ) : (
-            <span className="text-ink-soft">{item.label}</span>
+            <span className="text-ink-soft">
+              <MixedText>{item.label}</MixedText>
+            </span>
           )}
         </span>
       ))}

src/components/LoanCalculatorModal.tsx

@@ -0,0 +1,431 @@
+"use client";
+
+import Image from "next/image";
+import { useEffect, useMemo, useState } from "react";
+import { createPortal } from "react-dom";
+import { CheckIcon, CloseIcon, WalletIcon } from "./icons";
+import { clampCreditAmount, fetchStoreLoanMethods, fetchStoreLoanPlan } from "@/lib/loanMethods";
+import { formatPrice, toFaDigits } from "@/lib/format";
+import type { StoreLoanMethod, StoreLoanPlan } from "@/lib/types";
+
+type Props = {
+  open: boolean;
+  totalValue: number | null;
+  onClose: () => void;
+};
+
+function formatDueDate(iso: string) {
+  try {
+    return new Date(iso).toLocaleDateString("fa-IR", {
+      year: "numeric",
+      month: "long",
+      day: "numeric",
+    });
+  } catch {
+    return iso;
+  }
+}
+
+export default function LoanCalculatorModal({ open, totalValue, onClose }: Props) {
+  const [methods, setMethods] = useState<StoreLoanMethod[]>([]);
+  const [enabled, setEnabled] = useState(true);
+  const [loadingMethods, setLoadingMethods] = useState(false);
+  const [methodId, setMethodId] = useState<string | null>(null);
+  const [months, setMonths] = useState(0);
+  const [creditAmount, setCreditAmount] = useState(0);
+  const [plan, setPlan] = useState<StoreLoanPlan | null>(null);
+  const [calculating, setCalculating] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  const method = useMemo(
+    () => methods.find((m) => m.id === methodId) ?? null,
+    [methods, methodId],
+  );
+
+  const monthOptions = method?.returnMonthOptions?.length
+    ? method.returnMonthOptions
+    : method
+      ? Array.from(
+          { length: Math.floor((method.returnMonthsMax - method.returnMonthsMin) / method.returnMonthsStep) + 1 },
+          (_, i) => method.returnMonthsMin + i * method.returnMonthsStep,
+        )
+      : [];
+
+  const [mounted, setMounted] = useState(false);
+
+  useEffect(() => {
+    setMounted(true);
+  }, []);
+
+  // Load methods when opened.
+  useEffect(() => {
+    if (!open) return;
+    const controller = new AbortController();
+    let cancelled = false;
+    setLoadingMethods(true);
+    setError(null);
+    setPlan(null);
+    fetchStoreLoanMethods(controller.signal)
+      .then((data) => {
+        if (cancelled) return;
+        setEnabled(data.enabled);
+        setMethods(data.items);
+        if (data.items.length === 1) {
+          setMethodId(data.items[0]!.id);
+        } else if (data.items.length > 1) {
+          setMethodId(null);
+        }
+      })
+      .catch((err: unknown) => {
+        if (cancelled || (err as Error).name === "AbortError") return;
+        setEnabled(false);
+        setMethods([]);
+        setError("دریافت روش‌های اقساط ممکن نشد.");
+      })
+      .finally(() => {
+        if (!cancelled) setLoadingMethods(false);
+      });
+    return () => {
+      cancelled = true;
+      controller.abort();
+    };
+  }, [open]);
+
+  // When method or price changes, seed credit + months.
+  useEffect(() => {
+    if (!method || totalValue === null) return;
+    const credit = clampCreditAmount(
+      totalValue,
+      totalValue,
+      method.minAmount,
+      method.maxAmount,
+    );
+    setCreditAmount(credit);
+    const options = method.returnMonthOptions?.length
+      ? method.returnMonthOptions
+      : [method.returnMonthsMin];
+    setMonths(options[0] ?? method.returnMonthsMin);
+    setPlan(null);
+  }, [method, totalValue]);
+
+  // Calculate whenever inputs are ready.
+  useEffect(() => {
+    if (!open || !method || totalValue === null || months < 1 || creditAmount < 1) return;
+    if (totalValue < method.minShoppingAmount) {
+      setPlan(null);
+      setError(
+        `حداقل مبلغ خرید برای این طرح ${formatPrice(method.minShoppingAmount)} تومان است.`,
+      );
+      return;
+    }
+
+    const controller = new AbortController();
+    let cancelled = false;
+    const timer = setTimeout(() => {
+      setCalculating(true);
+      setError(null);
+      fetchStoreLoanPlan(
+        {
+          methodId: method.id,
+          totalValue,
+          creditAmount,
+          months,
+        },
+        controller.signal,
+      )
+        .then((data) => {
+          if (cancelled) return;
+          setPlan(data.plan);
+          setError(null);
+        })
+        .catch((err: unknown) => {
+          if (cancelled || (err as Error).name === "AbortError") return;
+          setPlan(null);
+          setError((err as Error).message || "محاسبه اقساط ناموفق بود.");
+        })
+        .finally(() => {
+          if (!cancelled) setCalculating(false);
+        });
+    }, 200);
+
+    return () => {
+      cancelled = true;
+      clearTimeout(timer);
+      controller.abort();
+    };
+  }, [open, method, totalValue, creditAmount, months]);
+
+  useEffect(() => {
+    if (!open) return;
+    const onKey = (e: KeyboardEvent) => {
+      if (e.key === "Escape") onClose();
+    };
+    document.addEventListener("keydown", onKey);
+    const prev = document.body.style.overflow;
+    document.body.style.overflow = "hidden";
+    return () => {
+      document.removeEventListener("keydown", onKey);
+      document.body.style.overflow = prev;
+    };
+  }, [open, onClose]);
+
+  if (!open || !mounted) return null;
+
+  const needsMethodPick = methods.length > 1 && !methodId;
+  const priceLabel = totalValue !== null ? formatPrice(totalValue) : "—";
+
+  return createPortal(
+    <div
+      className="fixed inset-0 z-50 flex items-end justify-center bg-ink/45 p-0 sm:items-center sm:p-4"
+      onClick={onClose}
+      role="presentation"
+    >
+      <div
+        className="flex max-h-[92vh] w-full max-w-lg flex-col overflow-hidden rounded-t-3xl bg-white shadow-2xl sm:rounded-3xl"
+        onClick={(e) => e.stopPropagation()}
+        role="dialog"
+        aria-modal="true"
+        aria-labelledby="loan-calc-title"
+      >
+        <div className="flex items-start justify-between gap-3 border-b border-line px-5 py-4">
+          <div className="min-w-0">
+            <p className="flex items-center gap-1.5 text-[12px] font-bold text-brand">
+              <WalletIcon className="size-4" />
+              محاسبه اقساط
+            </p>
+            <h2 id="loan-calc-title" className="mt-1 text-lg font-bold text-ink">
+              این محصول را اقساطی بخرید
+            </h2>
+            <p className="mt-0.5 text-[13px] text-body">
+              مبلغ کالا: <span className="font-bold text-ink">{priceLabel}</span>
+              {totalValue !== null && <span className="mr-1">تومان</span>}
+            </p>
+          </div>
+          <button
+            type="button"
+            onClick={onClose}
+            aria-label="بستن"
+            className="flex size-9 shrink-0 items-center justify-center rounded-full border border-line text-ink-soft transition hover:border-brand hover:text-brand"
+          >
+            <CloseIcon className="size-4.5" />
+          </button>
+        </div>
+
+        <div className="flex-1 space-y-5 overflow-y-auto px-5 py-5">
+          {loadingMethods && (
+            <p className="py-8 text-center text-sm text-body">در حال دریافت روش‌های اقساط…</p>
+          )}
+
+          {!loadingMethods && (!enabled || methods.length === 0) && (
+            <p className="rounded-xl bg-surface px-4 py-6 text-center text-sm text-body">
+              در حال حاضر فروش اقساطی برای این فروشگاه فعال نیست.
+            </p>
+          )}
+
+          {!loadingMethods && needsMethodPick && (
+            <section>
+              <h3 className="mb-3 text-sm font-bold text-ink">انتخاب طرح اقساط</h3>
+              <div className="space-y-2">
+                {methods.map((m) => (
+                  <button
+                    key={m.id}
+                    type="button"
+                    onClick={() => setMethodId(m.id)}
+                    className="flex w-full items-center gap-3 rounded-2xl border border-line p-3 text-start transition hover:border-brand"
+                  >
+                    <span className="relative size-12 shrink-0 overflow-hidden rounded-xl bg-surface">
+                      {m.imageUrl ? (
+                        <Image src={m.imageUrl} alt="" fill sizes="48px" className="object-cover" />
+                      ) : (
+                        <span className="flex size-full items-center justify-center text-brand">
+                          <WalletIcon className="size-5" />
+                        </span>
+                      )}
+                    </span>
+                    <span className="min-w-0 flex-1">
+                      <span className="block text-sm font-bold text-ink">{m.nameFa || m.nameEn}</span>
+                      {m.description && (
+                        <span className="mt-0.5 block text-[12px] text-body">{m.description}</span>
+                      )}
+                    </span>
+                  </button>
+                ))}
+              </div>
+            </section>
+          )}
+
+          {!loadingMethods && method && (
+            <>
+              {methods.length > 1 && (
+                <button
+                  type="button"
+                  onClick={() => {
+                    setMethodId(null);
+                    setPlan(null);
+                  }}
+                  className="text-[12.5px] font-bold text-brand"
+                >
+                  تغییر طرح: {method.nameFa || method.nameEn}
+                </button>
+              )}
+
+              {methods.length === 1 && (
+                <p className="rounded-xl bg-brand-soft px-3 py-2.5 text-[13px] font-bold text-brand">
+                  {method.nameFa || method.nameEn}
+                  {method.description ? ` — ${method.description}` : ""}
+                </p>
+              )}
+
+              <section>
+                <div className="mb-2 flex items-center justify-between">
+                  <h3 className="text-sm font-bold text-ink">مدت بازپرداخت</h3>
+                  <span className="text-sm font-black text-brand">
+                    {toFaDigits(months)} ماه
+                  </span>
+                </div>
+                <div className="flex flex-wrap gap-2">
+                  {monthOptions.map((m) => (
+                    <button
+                      key={m}
+                      type="button"
+                      onClick={() => setMonths(m)}
+                      className={`h-10 min-w-12 rounded-xl px-3 text-sm font-bold transition ${
+                        months === m
+                          ? "bg-brand text-white"
+                          : "border border-line text-ink hover:border-brand hover:text-brand"
+                      }`}
+                    >
+                      {toFaDigits(m)}
+                    </button>
+                  ))}
+                </div>
+                <p className="mt-2 text-[12px] text-body">
+                  سود سالانه {toFaDigits(method.interest)}٪ · اعتبار از{" "}
+                  {formatPrice(method.minAmount)} تا {formatPrice(method.maxAmount)} تومان
+                </p>
+              </section>
+
+              {totalValue !== null && totalValue > method.minAmount && (
+                <section>
+                  <div className="mb-2 flex items-center justify-between">
+                    <h3 className="text-sm font-bold text-ink">مبلغ اعتبار (قسطی)</h3>
+                    <span className="text-sm font-bold text-ink">
+                      {formatPrice(creditAmount)}
+                      <span className="mr-1 text-[11px] font-normal text-body">تومان</span>
+                    </span>
+                  </div>
+                  <input
+                    type="range"
+                    min={Math.min(method.minAmount, totalValue)}
+                    max={Math.min(method.maxAmount, totalValue)}
+                    step={100_000}
+                    value={creditAmount}
+                    onChange={(e) =>
+                      setCreditAmount(
+                        clampCreditAmount(
+                          Number(e.target.value),
+                          totalValue,
+                          method.minAmount,
+                          method.maxAmount,
+                        ),
+                      )
+                    }
+                    className="w-full accent-[var(--color-brand)]"
+                  />
+                  <div className="mt-1 flex justify-between text-[11px] text-body">
+                    <span>نقدی: {formatPrice(Math.max(0, totalValue - creditAmount))} تومان</span>
+                    <span>حداکثر اعتبار</span>
+                  </div>
+                </section>
+              )}
+
+              {error && (
+                <p className="rounded-xl bg-brand-soft px-3 py-2.5 text-[13px] text-brand" role="status">
+                  {error}
+                </p>
+              )}
+
+              {calculating && !plan && (
+                <p className="text-center text-sm text-body">در حال محاسبه…</p>
+              )}
+
+              {plan && !error && (
+                <section className="space-y-3">
+                  <h3 className="text-sm font-bold text-ink">جزئیات وام</h3>
+                  <div className="grid grid-cols-2 gap-2">
+                    <SummaryCard label="پرداخت نقدی" value={plan.cashPayment} />
+                    <SummaryCard label="مبلغ اعتبار" value={plan.creditAmount} />
+                    <SummaryCard label="کارمزد / سود" value={plan.interestFee} />
+                    <SummaryCard label="جمع بازپرداخت" value={plan.totalRepay} emphasize />
+                  </div>
+
+                  <div className="overflow-hidden rounded-2xl border border-line">
+                    <div className="flex items-center justify-between bg-surface px-3 py-2.5 text-[12.5px] font-bold text-ink">
+                      <span>جدول اقساط</span>
+                      <span>{toFaDigits(plan.installments.length)} قسط</span>
+                    </div>
+                    <ul className="max-h-56 divide-y divide-line overflow-y-auto">
+                      {plan.installments.map((item) => (
+                        <li
+                          key={item.index}
+                          className="flex items-center justify-between gap-3 px-3 py-2.5 text-[12.5px]"
+                        >
+                          <span className="flex items-center gap-2 text-body">
+                            <span className="flex size-6 items-center justify-center rounded-full bg-brand-soft text-[11px] font-bold text-brand">
+                              {toFaDigits(item.index)}
+                            </span>
+                            {formatDueDate(item.dueDate)}
+                          </span>
+                          <span className="shrink-0 font-bold text-ink">
+                            {formatPrice(item.amount)}
+                            <span className="mr-1 text-[10px] font-normal text-body">تومان</span>
+                          </span>
+                        </li>
+                      ))}
+                    </ul>
+                  </div>
+                </section>
+              )}
+            </>
+          )}
+        </div>
+
+        {plan && !error && (
+          <div className="border-t border-line px-5 py-4">
+            <p className="flex items-center justify-center gap-1.5 text-[12.5px] text-body">
+              <CheckIcon className="size-4 text-brand" />
+              برای نهایی کردن خرید اقساطی با فروشگاه هماهنگ کنید
+            </p>
+          </div>
+        )}
+      </div>
+    </div>,
+    document.body,
+  );
+}
+
+function SummaryCard({
+  label,
+  value,
+  emphasize,
+}: {
+  label: string;
+  value: number;
+  emphasize?: boolean;
+}) {
+  return (
+    <div
+      className={`rounded-2xl px-3 py-3 ${
+        emphasize ? "col-span-2 bg-brand text-white" : "bg-surface text-ink"
+      }`}
+    >
+      <p className={`text-[11px] ${emphasize ? "text-white/80" : "text-body"}`}>{label}</p>
+      <p className="mt-0.5 text-sm font-black">
+        {formatPrice(value)}
+        <span className={`mr-1 text-[10px] font-normal ${emphasize ? "text-white/80" : "text-body"}`}>
+          تومان
+        </span>
+      </p>
+    </div>
+  );
+}

src/components/MixedText.tsx

@@ -0,0 +1,23 @@
+import type { ReactNode } from "react";
+import { splitMixedText } from "@/lib/mixedText";
+
+export default function MixedText({
+  children,
+  className,
+}: {
+  children: string;
+  className?: string;
+}) {
+  const nodes: ReactNode[] = splitMixedText(children).map((seg, i) =>
+    seg.type === "en" ? (
+      <span key={i} className="en" dir="ltr" lang="en">
+        {seg.text}
+      </span>
+    ) : (
+      <span key={i}>{seg.text}</span>
+    ),
+  );
+
+  if (className) return <span className={className}>{nodes}</span>;
+  return <>{nodes}</>;
+}

src/components/ProductBuyPanel.tsx

@@ -1,7 +1,9 @@
 "use client";
 
-import { useState } from "react";
+import { useState, type ReactNode } from "react";
-import { CartIcon, CheckIcon, RotateIcon, ShieldIcon, TruckIcon } from "./icons";
+import { CartIcon, CheckIcon, ChevronLeft, RotateIcon, ShieldIcon, TruckIcon, WalletIcon } from "./icons";
+import LoanCalculatorModal from "./LoanCalculatorModal";
+import MixedText from "./MixedText";
 import { useCart } from "./providers/CartProvider";
 import { useToast } from "./providers/ToastProvider";
 import { formatPrice, isInStock, toFaDigits } from "@/lib/format";
@@ -25,17 +27,22 @@ export default function ProductBuyPanel({
   product,
   variants = [],
   initialVariantId,
+  gallery,
 }: {
   product: ApiProduct;
   variants?: StoreSpecialVariant[];
   /** Preselect a specific variant — used when entering via its own
    * /store-items/{id} URL rather than the product page. */
   initialVariantId?: string;
+  /** Optional gallery slot — when provided, the installment CTA spans the
+   * full product row (gallery + buy columns). */
+  gallery?: ReactNode;
 }) {
   const inStockVariants = variants.filter((v) => isInStock(v.stockQuantity));
   const [selectedId, setSelectedId] = useState(initialVariantId ?? inStockVariants[0]?.id);
   const [quantity, setQuantity] = useState(1);
   const [added, setAdded] = useState(false);
+  const [loanOpen, setLoanOpen] = useState(false);
   const { addItem } = useCart();
   const { showToast } = useToast();
   const selected = inStockVariants.find((v) => v.id === selectedId) ?? inStockVariants[0];
@@ -85,16 +92,20 @@ export default function ProductBuyPanel({
     setTimeout(() => setAdded(false), 1800);
   }
 
-  return (
+  const buyColumn = (
     <div className="grid grid-cols-1 gap-8 lg:grid-cols-[1fr_300px] md:gap-10">
       <div>
-        <h1 className="text-xl font-bold text-ink md:text-2xl">{title}</h1>
+        <h1 className="text-xl font-bold text-ink md:text-2xl">
+          <MixedText>{title}</MixedText>
+        </h1>
         {product.brand && <p className="mt-1.5 text-sm text-body">برند: {product.brand}</p>}
 
         {product.summary && (
           <div className="mt-5">
             <p className="mb-1.5 text-sm font-bold text-ink">توضیح کوتاه:</p>
-            <p className="text-sm leading-7 text-body">{product.summary}</p>
+            <p className="text-sm leading-7 text-body">
+              <MixedText>{product.summary}</MixedText>
+            </p>
           </div>
         )}
 
@@ -246,4 +257,45 @@ export default function ProductBuyPanel({
       </div>
     </div>
   );
+
+  const installmentRow = (
+    <button
+      type="button"
+      onClick={() => setLoanOpen(true)}
+      disabled={price === null}
+      className="group flex w-full items-center gap-4 overflow-hidden rounded-2xl bg-brand px-5 py-4 text-start text-white shadow-[0_8px_24px_-8px_rgba(229,30,34,0.55)] transition hover:bg-brand-dark disabled:cursor-not-allowed disabled:opacity-60 sm:px-6 sm:py-5"
+    >
+      <span className="flex size-12 shrink-0 items-center justify-center rounded-xl bg-white text-brand sm:size-14">
+        <WalletIcon className="size-6" />
+      </span>
+      <span className="min-w-0 flex-1">
+        <span className="block text-base font-black leading-7 sm:text-lg">این محصول را اقساطی بخرید</span>
+        <span className="mt-0.5 block text-[12.5px] font-bold text-white/85 sm:text-[13px]">
+          انتخاب مدت بازپرداخت و مشاهده جزئیات اقساط
+        </span>
+      </span>
+      <ChevronLeft className="size-5 shrink-0 transition group-hover:-translate-x-0.5 sm:size-6" />
+    </button>
+  );
+
+  return (
+    <>
+      {gallery ? (
+        <div className="space-y-6 md:space-y-8">
+          <div className="grid grid-cols-1 gap-8 md:gap-10 lg:grid-cols-[380px_1fr]">
+            {gallery}
+            {buyColumn}
+          </div>
+          {installmentRow}
+        </div>
+      ) : (
+        <div className="space-y-6">
+          {buyColumn}
+          {installmentRow}
+        </div>
+      )}
+
+      <LoanCalculatorModal open={loanOpen} totalValue={price} onClose={() => setLoanOpen(false)} />
+    </>
+  );
 }

src/components/ProductInfoTabs.tsx

@@ -2,6 +2,8 @@
 
 import { useState } from "react";
 import CommentSection from "./CommentSection";
+import MixedText from "./MixedText";
+import { wrapLatinInHtml } from "@/lib/mixedText";
 import type { AuthUser, EntityComment, SpecRow } from "@/lib/types";
 
 type Tab = "description" | "technical" | "reviews";
@@ -49,11 +51,13 @@ export default function ProductInfoTabs({
       <div className="pt-8">
         {tab === "description" && (
           <div>
-            <h2 className="mb-4 text-lg font-bold text-ink md:text-xl">معرفی {title}</h2>
+            <h2 className="mb-4 text-lg font-bold text-ink md:text-xl">
+              معرفی <MixedText>{title}</MixedText>
+            </h2>
             {descriptionHtml ? (
               <div
                 className="rich-text text-sm leading-8 text-body"
-                dangerouslySetInnerHTML={{ __html: descriptionHtml }}
+                dangerouslySetInnerHTML={{ __html: wrapLatinInHtml(descriptionHtml) }}
               />
             ) : (
               <p className="text-sm text-body">توضیحی برای این محصول ثبت نشده است.</p>
@@ -67,8 +71,12 @@ export default function ProductInfoTabs({
               <dl className="divide-y divide-line overflow-hidden rounded-xl border border-line">
                 {specRows.map((row) => (
                   <div key={row.key} className="flex justify-between gap-4 px-4 py-3 text-sm odd:bg-surface">
-                    <dt className="text-body">{row.label}</dt>
+                    <dt className="text-body">
-                    <dd className="font-bold text-ink">{row.value}</dd>
+                      <MixedText>{row.label}</MixedText>
+                    </dt>
+                    <dd className="font-bold text-ink">
+                      <MixedText>{row.value}</MixedText>
+                    </dd>
                   </div>
                 ))}
               </dl>

src/components/SearchBox.tsx

@@ -4,6 +4,7 @@ import Image from "next/image";
 import Link from "next/link";
 import { useEffect, useRef, useState } from "react";
 import { SearchIcon } from "./icons";
+import MixedText from "./MixedText";
 import { formatPrice } from "@/lib/format";
 import { productHref } from "@/lib/slug";
 import type { ApiProduct } from "@/lib/types";
@@ -110,7 +111,9 @@ export default function SearchBox() {
                       )}
                     </span>
                     <span className="min-w-0 flex-1">
-                      <span className="clamp-2 text-[13px] leading-6">{p.nameFa || p.title}</span>
+                      <span className="clamp-2 text-[13px] leading-6">
+                        <MixedText>{p.nameFa || p.title}</MixedText>
+                      </span>
                     </span>
                     {p.store.minPrice !== null && (
                       <span className="shrink-0 text-[12px] font-bold text-ink">

src/components/ui/ProductCard.tsx

@@ -1,5 +1,6 @@
 import Image from "next/image";
 import Link from "next/link";
+import MixedText from "@/components/MixedText";
 import { formatPrice, toFaDigits } from "@/lib/format";
 import type { ProductCardData } from "@/lib/types";
 
@@ -34,7 +35,7 @@ export default function ProductCard({ product }: { product: ProductCardData }) {
       </span>
 
       <span className="clamp-2 mb-3 min-h-[42px] px-1 text-[12.5px] leading-[21px] text-ink-soft">
-        {title}
+        <MixedText>{title}</MixedText>
       </span>
 
       {/* The old-price line always occupies its row — rendered empty when there

src/lib/api.ts

@@ -13,6 +13,8 @@ import type {
   StaticImageSlot,
   StoreItem,
   StoreItemVariants,
+  StoreLoanCalculateResponse,
+  StoreLoanMethodsResponse,
   StoreSpecial,
   Tenant,
   TechnicalInfoForm,
@@ -224,6 +226,21 @@ export function submitContactForm(
   return apiPost(t("/contact-submissions"), data);
 }
 
+// Installments module — AI_PROMPT.md "Installments & credit methods".
+// Hide the CTA when enabled:false or items is empty.
+export function getStoreLoanMethods(): Promise<StoreLoanMethodsResponse> {
+  return apiGet(t("/store-loan-methods"));
+}
+
+export function calculateStoreLoan(input: {
+  methodId: string;
+  totalValue: number;
+  creditAmount: number;
+  months: number;
+}): Promise<StoreLoanCalculateResponse> {
+  return apiPost(t("/store-loan-methods/calculate"), input);
+}
+
 // No cart functions here on purpose — AI_PROMPT.md "Hard rules" #3 and
 // "Shopping cart" are explicit that `/businesses/{id}/cart*` is
 // customer-dashboard-only. The mini-cart is local-only; see

src/lib/loanMethods.ts

@@ -0,0 +1,53 @@
+import { API_BASE, SITE_DOMAIN } from "./config";
+import type { StoreLoanCalculateResponse, StoreLoanMethodsResponse } from "./types";
+
+const base = `${API_BASE}/tenants/${SITE_DOMAIN}/store-loan-methods`;
+
+/** Browser-side list — same contract as GET .../store-loan-methods. */
+export async function fetchStoreLoanMethods(
+  signal?: AbortSignal,
+): Promise<StoreLoanMethodsResponse> {
+  const res = await fetch(base, { signal });
+  if (!res.ok) throw new Error(`loan methods failed (${res.status})`);
+  return res.json() as Promise<StoreLoanMethodsResponse>;
+}
+
+/** Browser-side calculate — POST .../store-loan-methods/calculate. */
+export async function fetchStoreLoanPlan(
+  input: {
+    methodId: string;
+    totalValue: number;
+    creditAmount: number;
+    months: number;
+  },
+  signal?: AbortSignal,
+): Promise<StoreLoanCalculateResponse> {
+  const res = await fetch(`${base}/calculate`, {
+    method: "POST",
+    headers: { "Content-Type": "application/json" },
+    body: JSON.stringify(input),
+    signal,
+  });
+  if (!res.ok) {
+    let message = `calculate failed (${res.status})`;
+    try {
+      const body = (await res.json()) as { message?: string };
+      if (body.message) message = body.message;
+    } catch {
+      /* ignore */
+    }
+    throw new Error(message);
+  }
+  return res.json() as Promise<StoreLoanCalculateResponse>;
+}
+
+export function clampCreditAmount(
+  value: number,
+  totalValue: number,
+  minAmount: number,
+  maxAmount: number,
+): number {
+  const upper = Math.min(Math.round(maxAmount), Math.round(totalValue));
+  const lower = Math.min(Math.round(minAmount), upper);
+  return Math.min(upper, Math.max(lower, Math.round(value)));
+}

src/lib/mixedText.ts

@@ -0,0 +1,44 @@
+// IRANYekan *fanum* maps Latin digit codepoints (0-9) to Persian glyphs.
+// Montserrat (`.en`) keeps real Latin digits — so any Latin-letter run that
+// also carries model numbers (HP R5, 8GB, EF2126WM…) must render under `.en`.
+// Pure digit runs (e.g. "13" inside «آیفون 13 پرو») stay on the FA font and
+// correctly show as Persian digits.
+const EN_RUN = /[A-Za-z0-9][A-Za-z0-9\s\-_|./+#%]*/g;
+
+export type TextSegment = { type: "fa" | "en"; text: string };
+
+export function splitMixedText(text: string): TextSegment[] {
+  const segments: TextSegment[] = [];
+  let cursor = 0;
+  let match: RegExpExecArray | null;
+  const re = new RegExp(EN_RUN.source, "g");
+
+  while ((match = re.exec(text)) !== null) {
+    let start = match.index;
+    let end = start + match[0].length;
+    while (end > start && /\s/.test(text[end - 1]!)) end--;
+    const chunk = text.slice(start, end);
+    if (!/[A-Za-z]/.test(chunk)) continue;
+
+    if (start > cursor) segments.push({ type: "fa", text: text.slice(cursor, start) });
+    segments.push({ type: "en", text: chunk });
+    cursor = end;
+  }
+
+  if (cursor < text.length) segments.push({ type: "fa", text: text.slice(cursor) });
+  return segments;
+}
+
+/** Wrap Latin runs in a plain string as `.en` spans (text is assumed already HTML-safe). */
+export function wrapLatinRuns(text: string): string {
+  return splitMixedText(text)
+    .map((seg) =>
+      seg.type === "en" ? `<span class="en" dir="ltr" lang="en">${seg.text}</span>` : seg.text,
+    )
+    .join("");
+}
+
+/** Walk HTML text nodes (content between tags) and wrap Latin runs. */
+export function wrapLatinInHtml(html: string): string {
+  return html.replace(/(^|>)([^<]+)/g, (_, prefix: string, text: string) => prefix + wrapLatinRuns(text));
+}

src/lib/types.ts

@@ -315,3 +315,48 @@ export interface AuthUser {
 // src/lib/guestCart.ts for GuestCartItem) — there is no server Cart/CartItem
 // type here on purpose, calling /businesses/{id}/cart* from this site is
 // against the documented contract.
+
+// GET /tenants/{domain}/store-loan-methods — hide UI when enabled:false / empty.
+export interface StoreLoanMethod {
+  id: string;
+  nameFa: string;
+  nameEn: string;
+  description: string | null;
+  imageUrl: string | null;
+  imageAspectRatio: string;
+  minShoppingAmount: number;
+  minAmount: number;
+  maxAmount: number;
+  interest: number;
+  returnMonthsMin: number;
+  returnMonthsMax: number;
+  returnMonthsStep: number;
+  returnMonthOptions: number[];
+  sortOrder: number;
+}
+
+export interface StoreLoanMethodsResponse {
+  enabled: boolean;
+  items: StoreLoanMethod[];
+}
+
+export interface StoreLoanInstallment {
+  index: number;
+  dueDate: string;
+  amount: number;
+}
+
+export interface StoreLoanPlan {
+  totalValue: number;
+  creditAmount: number;
+  cashPayment: number;
+  interestFee: number;
+  totalRepay: number;
+  months: number;
+  installments: StoreLoanInstallment[];
+}
+
+export interface StoreLoanCalculateResponse {
+  method: StoreLoanMethod;
+  plan: StoreLoanPlan;
+}