diff --git a/docker/frontend/src/engine/exportEngine.ts b/docker/frontend/src/engine/exportEngine.ts
index 16fed42..19c953b 100644
--- a/docker/frontend/src/engine/exportEngine.ts
+++ b/docker/frontend/src/engine/exportEngine.ts
@@ -1079,7 +1079,7 @@ async function applyHealToBase(
         const cSpanW = mx1 - mx0;
         const cSpanH = my1 - my0;
         const cSpan = Math.max(cSpanW, cSpanH);
-        const margin = Math.max(96, Math.min(512, Math.round(cWidest * 3 + cSpan * 0.8)));
+        const margin = Math.max(24, Math.min(96, Math.round(cWidest * 2 + 16)));
         const srcLeft = Math.max(boxLeft, Math.floor(mx0 - margin));
         const srcTop = Math.max(boxTop, Math.floor(my0 - margin));
         const srcRight = Math.min(boxRight, Math.ceil(mx1 + margin));
diff --git a/docker/frontend/src/engine/inpaint.ts b/docker/frontend/src/engine/inpaint.ts
index 0243baf..8be30e0 100644
--- a/docker/frontend/src/engine/inpaint.ts
+++ b/docker/frontend/src/engine/inpaint.ts
@@ -344,16 +344,35 @@ export function fastLocalInpaint(
   const total = w * h;
   const clean = new Uint8Array(total);
   let holeCount = 0;
-  for (let i = 0; i < total; i++) {
-    if (!hole[i]) clean[i] = 1;
-    else holeCount++;
+  let ymin = h, ymax = -1, xmin = w, xmax = -1;
+
+  for (let y = 0; y < h; y++) {
+    const row = y * w;
+    for (let x = 0; x < w; x++) {
+      const idx = row + x;
+      if (!hole[idx]) {
+        clean[idx] = 1;
+      } else {
+        holeCount++;
+        if (y < ymin) ymin = y;
+        if (y > ymax) ymax = y;
+        if (x < xmin) xmin = x;
+        if (x > xmax) xmax = x;
+      }
+    }
   }
-  if (holeCount === 0) {
+
+  if (holeCount === 0 || holeCount === total) {
     const res = new Uint8Array(rgba.length);
     res.set(rgba);
     return res;
   }
 
+  ymin = Math.max(1, ymin - 1);
+  ymax = Math.min(h - 2, ymax + 1);
+  xmin = Math.max(1, xmin - 1);
+  xmax = Math.min(w - 2, xmax + 1);
+
   // 1. Two-pass Euclidean Vector Distance Transform (EDT)
   const ny = new Int16Array(total);
   const nx = new Int16Array(total);
@@ -445,7 +464,7 @@ export function fastLocalInpaint(
     }
   }
 
-  // 2. Base structural layer: Dirichlet Poisson / Laplace solve (∇² I = 0)
+  // 2. Base structural layer: Dirichlet Poisson / Laplace solve (∇² I = 0) with SOR
   const baseR = new Float32Array(total);
   const baseG = new Float32Array(total);
   const baseB = new Float32Array(total);
@@ -464,27 +483,33 @@ export function fastLocalInpaint(
     }
   }
 
-  // Gauss-Seidel Poisson relaxation (25 passes guarantees smooth harmonic convergence inside hole)
-  for (let it = 0; it < 25; it++) {
-    for (let y = 0; y < h; y++) {
+  // Successive Over-Relaxation (SOR) with omega = 1.75
+  const omega = 1.75;
+  const oneMinusOmega = 1.0 - omega;
+  for (let it = 0; it < 35; it++) {
+    for (let y = ymin; y <= ymax; y++) {
       const row = y * w;
-      for (let x = 0; x < w; x++) {
+      for (let x = xmin; x <= xmax; x++) {
         const idx = row + x;
         if (clean[idx]) continue;
 
-        const up = y > 0 ? idx - w : idx;
-        const down = y < h - 1 ? idx + w : idx;
-        const left = x > 0 ? idx - 1 : idx;
-        const right = x < w - 1 ? idx + 1 : idx;
+        const up = idx - w;
+        const down = idx + w;
+        const left = idx - 1;
+        const right = idx + 1;
 
-        baseR[idx] = 0.25 * (baseR[up] + baseR[down] + baseR[left] + baseR[right]);
-        baseG[idx] = 0.25 * (baseG[up] + baseG[down] + baseG[left] + baseG[right]);
-        baseB[idx] = 0.25 * (baseG[up] + baseG[down] + baseG[left] + baseG[right]);
+        const avgR = (baseR[up] + baseR[down] + baseR[left] + baseR[right]) * 0.25;
+        const avgG = (baseG[up] + baseG[down] + baseG[left] + baseG[right]) * 0.25;
+        const avgB = (baseB[up] + baseB[down] + baseB[left] + baseB[right]) * 0.25;
+
+        baseR[idx] = oneMinusOmega * baseR[idx] + omega * avgR;
+        baseG[idx] = oneMinusOmega * baseG[idx] + omega * avgG;
+        baseB[idx] = oneMinusOmega * baseB[idx] + omega * avgB;
       }
     }
   }
 
-  // 3. Separable 5-tap Gaussian Filter on original image
+  // 3. Separable 5-tap Gaussian Filter on original image to extract high-pass micro-texture
   const tempR = new Float32Array(total);
   const tempG = new Float32Array(total);
   const tempB = new Float32Array(total);
@@ -524,23 +549,231 @@ export function fastLocalInpaint(
     }
   }
 
-  // 4. Coherent texture transfer & final assembly
+  // 4. Structure Tensor on local clean boundary band (within 12px)
+  let sumGxx = 0, sumGyy = 0, sumGxy = 0, bandCount = 0;
+  let hpVarSum = 0;
+
+  for (let y = ymin; y <= ymax; y++) {
+    const row = y * w;
+    for (let x = xmin; x <= xmax; x++) {
+      const idx = row + x;
+      if (!clean[idx]) continue;
+      const d = dsq[idx];
+      // Clean pixels close to hole boundary
+      if (d > 0 && d <= 144) {
+        const p = idx << 2;
+        const lum = rgba[p] * 0.299 + rgba[p + 1] * 0.587 + rgba[p + 2] * 0.114;
+        const lumL = rgba[(row + Math.max(0, x - 1)) << 2] * 0.299 + rgba[(row + Math.max(0, x - 1)) << 2 + 1] * 0.587 + rgba[(row + Math.max(0, x - 1)) << 2 + 2] * 0.114;
+        const lumR = rgba[(row + Math.min(w - 1, x + 1)) << 2] * 0.299 + rgba[(row + Math.min(w - 1, x + 1)) << 2 + 1] * 0.587 + rgba[(row + Math.min(w - 1, x + 1)) << 2 + 2] * 0.114;
+        const lumT = rgba[(Math.max(0, y - 1) * w + x) << 2] * 0.299 + rgba[(Math.max(0, y - 1) * w + x) << 2 + 1] * 0.587 + rgba[(Math.max(0, y - 1) * w + x) << 2 + 2] * 0.114;
+        const lumB = rgba[(Math.min(h - 1, y + 1) * w + x) << 2] * 0.299 + rgba[(Math.min(h - 1, y + 1) * w + x) << 2 + 1] * 0.587 + rgba[(Math.min(h - 1, y + 1) * w + x) << 2 + 2] * 0.114;
+
+        const gx = (lumR - lumL) * 0.5;
+        const gy = (lumB - lumT) * 0.5;
+
+        sumGxx += gx * gx;
+        sumGyy += gy * gy;
+        sumGxy += gx * gy;
+        bandCount++;
+
+        const diffR = rgba[p] - meanR[idx];
+        const diffG = rgba[p + 1] - meanG[idx];
+        const diffB = rgba[p + 2] - meanB[idx];
+        hpVarSum += diffR * diffR + diffG * diffG + diffB * diffB;
+      }
+    }
+  }
+
+  let coherence = 0;
+  if (bandCount > 0) {
+    const jxx = sumGxx / bandCount;
+    const jyy = sumGyy / bandCount;
+    const jxy = sumGxy / bandCount;
+    const tr = jxx + jyy;
+    const det = jxx * jyy - jxy * jxy;
+    const diffEig = Math.sqrt(Math.max(0, tr * tr - 4 * det));
+    const l1 = (tr + diffEig) * 0.5;
+    const l2 = (tr - diffEig) * 0.5;
+    if (l1 + l2 > 0) {
+      coherence = (l1 - l2) / (l1 + l2);
+    }
+  }
+
+  const isHorizontalDominant = coherence > 0.25 && sumGyy > 1.5 * sumGxx;
+  const isVerticalDominant = coherence > 0.25 && sumGxx > 1.5 * sumGyy;
+
+  // 5. Directional high-pass synthesis
+  const hpR = new Float32Array(total);
+  const hpG = new Float32Array(total);
+  const hpB = new Float32Array(total);
+
+  if (isHorizontalDominant) {
+    // Water ripples or horizontal grain: bridge along rows
+    for (let y = ymin; y <= ymax; y++) {
+      const row = y * w;
+      for (let x = xmin; x <= xmax; x++) {
+        const idx = row + x;
+        if (clean[idx]) continue;
+
+        let xl = x;
+        while (xl >= 0 && !clean[row + xl]) xl--;
+        let xr = x;
+        while (xr < w && !clean[row + xr]) xr++;
+
+        if (xl >= 0 && xr < w) {
+          const dl = x - xl;
+          const dr = xr - x;
+          const t = dl / (dl + dr);
+          const st = t * t * (3 - 2 * t);
+
+          const idxL = row + xl;
+          const idxR = row + xr;
+          const dpL = idxL << 2;
+          const dpR = idxR << 2;
+
+          const texRL = rgba[dpL] - meanR[idxL];
+          const texGL = rgba[dpL + 1] - meanG[idxL];
+          const texBL = rgba[dpL + 2] - meanB[idxL];
+
+          const texRR = rgba[dpR] - meanR[idxR];
+          const texGR = rgba[dpR + 1] - meanG[idxR];
+          const texBR = rgba[dpR + 2] - meanB[idxR];
+
+          hpR[idx] = (1 - st) * texRL + st * texRR;
+          hpG[idx] = (1 - st) * texGL + st * texGR;
+          hpB[idx] = (1 - st) * texBL + st * texBR;
+        } else if (xl >= 0) {
+          const idxL = row + xl;
+          const dpL = idxL << 2;
+          hpR[idx] = rgba[dpL] - meanR[idxL];
+          hpG[idx] = rgba[dpL + 1] - meanG[idxL];
+          hpB[idx] = rgba[dpL + 2] - meanB[idxL];
+        } else if (xr < w) {
+          const idxR = row + xr;
+          const dpR = idxR << 2;
+          hpR[idx] = rgba[dpR] - meanR[idxR];
+          hpG[idx] = rgba[dpR + 1] - meanG[idxR];
+          hpB[idx] = rgba[dpR + 2] - meanB[idxR];
+        } else {
+          const donor = ny[idx] * w + nx[idx];
+          const dp = donor << 2;
+          hpR[idx] = rgba[dp] - meanR[donor];
+          hpG[idx] = rgba[dp + 1] - meanG[donor];
+          hpB[idx] = rgba[dp + 2] - meanB[donor];
+        }
+      }
+    }
+  } else if (isVerticalDominant) {
+    // Vertical lines or columns: bridge along columns
+    for (let y = ymin; y <= ymax; y++) {
+      const row = y * w;
+      for (let x = xmin; x <= xmax; x++) {
+        const idx = row + x;
+        if (clean[idx]) continue;
+
+        let yt = y;
+        while (yt >= 0 && !clean[yt * w + x]) yt--;
+        let yb = y;
+        while (yb < h && !clean[yb * w + x]) yb++;
+
+        if (yt >= 0 && yb < h) {
+          const dt = y - yt;
+          const db = yb - y;
+          const t = dt / (dt + db);
+          const st = t * t * (3 - 2 * t);
+
+          const idxT = yt * w + x;
+          const idxB = yb * w + x;
+          const dpT = idxT << 2;
+          const dpB = idxB << 2;
+
+          const texRT = rgba[dpT] - meanR[idxT];
+          const texGT = rgba[dpT + 1] - meanG[idxT];
+          const texBT = rgba[dpT + 2] - meanB[idxT];
+
+          const texRB = rgba[dpB] - meanR[idxB];
+          const texGB = rgba[dpB + 1] - meanG[idxB];
+          const texBB = rgba[dpB + 2] - meanB[idxB];
+
+          hpR[idx] = (1 - st) * texRT + st * texRB;
+          hpG[idx] = (1 - st) * texGT + st * texGB;
+          hpB[idx] = (1 - st) * texBT + st * texBB;
+        } else if (yt >= 0) {
+          const idxT = yt * w + x;
+          const dpT = idxT << 2;
+          hpR[idx] = rgba[dpT] - meanR[idxT];
+          hpG[idx] = rgba[dpT + 1] - meanG[idxT];
+          hpB[idx] = rgba[dpT + 2] - meanB[idxT];
+        } else if (yb < h) {
+          const idxB = yb * w + x;
+          const dpB = idxB << 2;
+          hpR[idx] = rgba[dpB] - meanR[idxB];
+          hpG[idx] = rgba[dpB + 1] - meanG[idxB];
+          hpB[idx] = rgba[dpB + 2] - meanB[idxB];
+        } else {
+          const donor = ny[idx] * w + nx[idx];
+          const dp = donor << 2;
+          hpR[idx] = rgba[dp] - meanR[donor];
+          hpG[idx] = rgba[dp + 1] - meanG[donor];
+          hpB[idx] = rgba[dp + 2] - meanB[donor];
+        }
+      }
+    }
+  } else {
+    // Isotropic texture (skin, sky, plaster): sample from closest boundary
+    for (let y = ymin; y <= ymax; y++) {
+      const row = y * w;
+      for (let x = xmin; x <= xmax; x++) {
+        const idx = row + x;
+        if (clean[idx]) continue;
+        const donor = ny[idx] * w + nx[idx];
+        const dp = donor << 2;
+        hpR[idx] = rgba[dp] - meanR[donor];
+        hpG[idx] = rgba[dp + 1] - meanG[donor];
+        hpB[idx] = rgba[dp + 2] - meanB[donor];
+      }
+    }
+    // 2-pass light diffusion to eliminate Voronoi facets
+    for (let it = 0; it < 2; it++) {
+      for (let y = ymin; y <= ymax; y++) {
+        const row = y * w;
+        for (let x = xmin; x <= xmax; x++) {
+          const idx = row + x;
+          if (clean[idx]) continue;
+          hpR[idx] = 0.25 * (hpR[idx - w] + hpR[idx + w] + hpR[idx - 1] + hpR[idx + 1]);
+          hpG[idx] = 0.25 * (hpG[idx - w] + hpG[idx + w] + hpG[idx - 1] + hpG[idx + 1]);
+          hpB[idx] = 0.25 * (hpB[idx - w] + hpB[idx + w] + hpB[idx - 1] + hpB[idx + 1]);
+        }
+      }
+    }
+  }
+
+  // 6. Camera sensor grain
+  const grainStd = bandCount > 0 ? Math.min(1.2, Math.sqrt(hpVarSum / (bandCount * 3)) * 0.4) : 0.8;
+  let seed = (ymin * 31 + xmin * 17) | 1;
+  const randNorm = () => {
+    seed = (seed * 16807) % 2147483647;
+    const u1 = Math.max(1e-7, seed / 2147483647);
+    seed = (seed * 16807) % 2147483647;
+    const u2 = seed / 2147483647;
+    return Math.sqrt(-2.0 * Math.log(u1)) * Math.cos(2.0 * Math.PI * u2);
+  };
+
+  // 7. Final assembly
   const out = new Uint8Array(4 * total);
   out.set(rgba);
 
-  for (let i = 0; i < total; i++) {
-    if (!clean[i]) {
-      const donor = ny[i] * w + nx[i];
-      const dp = donor << 2;
+  for (let y = ymin; y <= ymax; y++) {
+    const row = y * w;
+    for (let x = xmin; x <= xmax; x++) {
+      const idx = row + x;
+      if (clean[idx]) continue;
 
-      const texR = rgba[dp] - meanR[donor];
-      const texG = rgba[dp + 1] - meanG[donor];
-      const texB = rgba[dp + 2] - meanB[donor];
-
-      const p = i << 2;
-      const r = Math.round(baseR[i] + texR);
-      const g = Math.round(baseG[i] + texG);
-      const b = Math.round(baseB[i] + texB);
+      const p = idx << 2;
+      const noise = randNorm() * grainStd;
+      const r = Math.round(baseR[idx] + hpR[idx] * 0.85 + noise);
+      const g = Math.round(baseG[idx] + hpG[idx] * 0.85 + noise);
+      const b = Math.round(baseB[idx] + hpB[idx] * 0.85 + noise);
 
       out[p] = r < 0 ? 0 : r > 255 ? 255 : r;
       out[p + 1] = g < 0 ? 0 : g > 255 ? 255 : g;
@@ -631,13 +864,6 @@ export async function inpaintCrop(
   height: number,
   hole: Uint8Array
 ): Promise<Uint8Array | null> {
-  const maxSide = isMobile() ? 256 : INPAINT_MAX_SIDE;
-  let w = Math.max(8, Math.round(width));
-  let h = Math.max(8, Math.round(height));
-  const scale = Math.min(1, maxSide / Math.max(w, h));
-  w = Math.max(8, Math.floor((w * scale) / 8) * 8);
-  h = Math.max(8, Math.floor((h * scale) / 8) * 8);
-
   const patchKey = (hole as { patchKey?: string }).patchKey;
   let key: string;
   if (patchKey) {
@@ -652,97 +878,27 @@ export async function inpaintCrop(
         holeHash = (holeHash * 31 + i) | 0;
       }
     }
-    key = `${w}x${h}_${holeCount}_${holeHash}`;
+    key = `${width}x${height}_${holeCount}_${holeHash}`;
   }
 
   if (patchCache.has(key)) {
     return patchCache.get(key)!.slice();
   }
 
-  // On mobile devices (iOS Safari/Chrome WebKit), running the 28MB ONNX neural model
-  // in WebAssembly exceeds the tab's strict Jetsam memory quota and triggers process termination (tab reload).
-  // Use fastLocalInpaint directly: pure TypeScript, <2MB RAM, ~10ms execution, 100% crash-free.
-  if (isMobile()) {
-    const patch = fastLocalInpaint(rgba, width, height, hole);
-    if (patchCache.size > 50) {
-      const first = patchCache.keys().next().value;
-      if (first) patchCache.delete(first);
-    }
-    patchCache.set(key, patch.slice());
-    return patch;
-  }
-
-  // Single-flight lock: serialize inference executions to prevent memory spikes
-  if (inFlightInpaint) {
-    try {
-      await inFlightInpaint;
-    } catch {}
-    if (patchCache.has(key)) {
-      return patchCache.get(key)!.slice();
-    }
-  }
-
-  const runPromise = (async (): Promise<Uint8Array | null> => {
-    const { src, hole: mask } = cropPlate(rgba, width, height, hole, w, h);
-
-    let in0: Ort.Tensor | null = null;
-    let in1: Ort.Tensor | null = null;
-    let out: Record<string, Ort.Tensor> | null = null;
-    try {
-      const { ort, session } = await load();
-      in0 = new ort.Tensor('uint8', src, [1, 3, h, w]);
-      in1 = new ort.Tensor('uint8', mask, [1, 1, h, w]);
-      out = await session.run({
-        [session.inputNames[0]]: in0,
-        [session.inputNames[1]]: in1,
-      });
-      const tensor = out[session.outputNames[0]];
-      const oplane = w * h;
-      const data = tensor.data as Uint8Array;
-      const patch = new Uint8Array(4 * w * h);
-      for (let i = 0; i < oplane; i++) {
-        patch[i * 4] = data[i];
-        patch[i * 4 + 1] = data[oplane + i];
-        patch[i * 4 + 2] = data[2 * oplane + i];
-        patch[i * 4 + 3] = 255;
-      }
-      // Re-apply coherent photographic micro-texture & grain onto neural output to eliminate all blur
-      const sharpPatch = applyCoherentTexture(patch, rgba, w, h, hole);
-      if (patchCache.size > 50) {
-        const first = patchCache.keys().next().value;
-        if (first) patchCache.delete(first);
-      }
-      patchCache.set(key, sharpPatch.slice());
-      return sharpPatch;
-    } catch (err) {
-      console.warn('[inpaint] neural inference error, fallback to local inpaint:', err);
-      return fastLocalInpaint(rgba, width, height, hole);
-    } finally {
-      try {
-        in0?.dispose?.();
-        in1?.dispose?.();
-        if (out) {
-          for (const k in out) out[k]?.dispose?.();
-        }
-      } catch {}
-    }
-  })();
-
-  inFlightInpaint = runPromise;
-  try {
-    return await runPromise;
-  } finally {
-    if (inFlightInpaint === runPromise) {
-      inFlightInpaint = null;
-    }
+  const patch = fastLocalInpaint(rgba, width, height, hole);
+  if (patchCache.size > 50) {
+    const first = patchCache.keys().next().value;
+    if (first) patchCache.delete(first);
   }
+  patchCache.set(key, patch.slice());
+  return patch;
 }
 
 export function inpaintCropSize(width: number, height: number): { w: number; h: number } {
-  const maxSide = isMobile() ? 256 : INPAINT_MAX_SIDE;
+  const maxSide = INPAINT_MAX_SIDE;
   const scale = Math.min(1, maxSide / Math.max(1, Math.max(width, height)));
   return {
-    w: Math.max(8, Math.floor((Math.max(1, Math.round(width)) * scale) / 8) * 8),
-    h: Math.max(8, Math.floor((Math.max(1, Math.round(height)) * scale) / 8) * 8),
+    w: Math.max(1, Math.round(width * scale)),
+    h: Math.max(1, Math.round(height * scale)),
   };
 }