diff --git a/avia_core/clientBackup.js b/avia_core/clientBackup.js
new file mode 100644
index 0000000..c62cc03
--- /dev/null
+++ b/avia_core/clientBackup.js
@@ -0,0 +1,175 @@
+(function () {
+  if (window.__clientBackup) return;
+  window.__clientBackup = true;
+
+  const TARGET_TEXT = "Spellchecker";
+  const CLONE_KEY   = "data-lsbackup-cloned";
+
+  function exportLS() {
+    const data = {};
+    for (let i = 0; i < localStorage.length; i++) {
+      const key = localStorage.key(i);
+      data[key] = localStorage.getItem(key);
+    }
+    const blob = new Blob([JSON.stringify(data, null, 2)], { type: "application/json" });
+    const url  = URL.createObjectURL(blob);
+    const a    = document.createElement("a");
+    a.href     = url;
+    a.download = "localstorage-backup.json";
+    a.click();
+    URL.revokeObjectURL(url);
+  }
+
+  function importLS(file, onDone) {
+    const reader = new FileReader();
+    reader.onload = e => {
+      try {
+        const data = JSON.parse(e.target.result);
+        let count = 0;
+        for (const [key, value] of Object.entries(data)) {
+          localStorage.setItem(key, value);
+          count++;
+        }
+        onDone(null, count);
+      } catch (err) {
+        onDone(err);
+      }
+    };
+    reader.readAsText(file);
+  }
+
+  function buildPanel() {
+    const panel = document.createElement("div");
+    panel.style.cssText = `
+      display: none;
+      flex-direction: column;
+      gap: 8px;
+      padding: 10px 12px;
+      border-radius: 8px;
+      background: var(--md-sys-color-surface-container-highest);
+      border: 1px solid var(--md-sys-color-outline-variant);
+      font-size: 12px;
+      color: var(--md-sys-color-on-surface);
+    `;
+
+    const btnStyle = `
+      padding: 5px 12px;
+      border-radius: 4px;
+      border: none;
+      font-size: 11px;
+      font-weight: 600;
+      cursor: pointer;
+    `;
+
+    const status = document.createElement("span");
+    status.style.cssText = "font-size: 11px; opacity: 0.7; min-height: 14px;";
+
+    const exportBtn = document.createElement("button");
+    exportBtn.textContent = "⬇ Export localStorage";
+    exportBtn.style.cssText = btnStyle + `
+      background: var(--md-sys-color-primary);
+      color: var(--md-sys-color-on-primary);
+    `;
+    exportBtn.addEventListener("click", e => {
+      e.preventDefault();
+      e.stopPropagation();
+      exportLS();
+      status.textContent = `✓ Exported ${localStorage.length} keys`;
+    });
+
+    const fileInput = document.createElement("input");
+    fileInput.type   = "file";
+    fileInput.accept = ".json";
+    fileInput.style.cssText = "display: none;";
+    fileInput.addEventListener("change", e => {
+      const file = e.target.files[0];
+      if (!file) return;
+      importLS(file, (err, count) => {
+        if (err) {
+          status.textContent = "✗ Invalid JSON file";
+        } else {
+          status.textContent = `✓ Imported ${count} keys`;
+        }
+        fileInput.value = "";
+      });
+    });
+
+    const importBtn = document.createElement("button");
+    importBtn.textContent = "⬆ Import localStorage";
+    importBtn.style.cssText = btnStyle + `
+      background: var(--md-sys-color-surface-container);
+      color: var(--md-sys-color-on-surface);
+      border: 1px solid var(--md-sys-color-outline-variant);
+    `;
+    importBtn.addEventListener("click", e => {
+      e.preventDefault();
+      e.stopPropagation();
+      fileInput.click();
+    });
+
+    panel.appendChild(exportBtn);
+    panel.appendChild(importBtn);
+    panel.appendChild(fileInput);
+    panel.appendChild(status);
+    return panel;
+  }
+
+  function tryInject() {
+    document.querySelectorAll("a.pos_relative").forEach(btn => {
+      if (
+        btn.hasAttribute(CLONE_KEY) ||
+        btn.hasAttribute("data-lsbackup-entry") ||
+        !btn.innerText.includes(TARGET_TEXT)
+      ) return;
+
+      btn.setAttribute(CLONE_KEY, "true");
+
+      const clone = btn.cloneNode(true);
+      clone.removeAttribute(CLONE_KEY);
+      clone.setAttribute("data-lsbackup-entry", "true");
+
+      const title = clone.querySelector("div.d_flex.flex-g_1.flex-d_column > div");
+      if (title) title.textContent = "AviaClient Backup";
+
+      const desc = clone.querySelector("div.d_flex.flex-g_1.flex-d_column > span");
+      if (desc) desc.textContent = "Backup or Restore all client data";
+
+      const iconBtn = document.createElement("div");
+      iconBtn.title = "LocalStorage Backup";
+      iconBtn.style.cssText = "cursor: pointer; z-index: 10; flex-shrink: 0;";
+      iconBtn.innerHTML = `
+        <div class="fill_var(--md-sys-color-on-surface) bg_var(--md-sys-color-surface-dim) w_36px h_36px d_flex flex-sh_0 ai_center jc_center bdr_var(--borderRadius-full)">
+          <span aria-hidden="true" class="material-symbols-outlined fs_inherit fw_undefined!" style="display: block; font-variation-settings: 'FILL' 0, 'wght' 400, 'GRAD' 0;">database</span>
+        </div>
+      `;
+
+      const existingIcon = clone.querySelector("div.fill_var\\(--md-sys-color-on-surface\\)");
+      if (existingIcon) {
+        existingIcon.replaceWith(iconBtn);
+      } else {
+        clone.prepend(iconBtn);
+      }
+
+      clone.addEventListener("click", e => {
+        e.preventDefault();
+        e.stopPropagation();
+        panel.style.display = panel.style.display === "flex" ? "none" : "flex";
+      });
+
+      const wrapper = document.createElement("div");
+      wrapper.style.cssText = "display: flex; flex-direction: column;";
+
+      const panel = buildPanel();
+
+      wrapper.appendChild(clone);
+      wrapper.appendChild(panel);
+
+      btn.parentNode.insertBefore(wrapper, btn.nextSibling);
+    });
+  }
+
+  tryInject();
+
+  const observer = new MutationObserver(() => tryInject());
+  observer.observe(document.body, { childList: true, subtree: true });
+})();