diff --git a/assets/js/main.js b/assets/js/main.js
index 77791ed..fe13355 100644
--- a/assets/js/main.js
+++ b/assets/js/main.js
@@ -301,12 +301,14 @@ async function genCode() {
   const privacy = optPrivacy.options[optPrivacy.selectedIndex].value
   const hashStr = hashExp ? bytesToB64(hashExp) : ''
   const urlsStr = imgUrls.join("', '")
+  let pathPrefix = document.getElementById('pathPrefix').value.replaceAll('/', '').replaceAll('\\', '')
   let js = `\
 var HASH = '${hashStr}'
 var URLS = ['${urlsStr}']
 var PRIVACY = ${privacy}
 var UPDATE_INTERVAL = 120
 var IMG_TIMEOUT = 10
+var PATH_PREFIX = '${pathPrefix}'
 
 ${tmplCode}
 `
diff --git a/assets/js/tmpl.js b/assets/js/tmpl.js
index 5940397..12ac606 100644
--- a/assets/js/tmpl.js
+++ b/assets/js/tmpl.js
@@ -22,7 +22,7 @@ function pageEnv() {
     var pendings = []
 
     if (!sw.controller) {
-      var swPending = sw.register(jsUrl).catch(function(err) {
+      var swPending = sw.register(jsUrl, {scope: getRootPath(jsUrl)}).catch(function(err) {
         fallback(err.message)
       })
       pendings.push(swPending)
@@ -46,7 +46,8 @@ function pageEnv() {
       )
     }
     Promise.all(pendings).then(function() {
-      location.reload()
+      // location.reload()
+      location.replace(getRootPath(jsUrl))
     })
   }
 
@@ -295,7 +296,8 @@ function getRootPath(url) {
   // e.g.
   // 'https://mysite.com/'
   // 'https://xx.github.io/path/to/'
-  return url.split('?')[0].replace(/[^/]+$/, '')
+  return url.split('?')[0].replace(/[^/]+$/, '') + (PATH_PREFIX ? PATH_PREFIX + '/' : '')
+
 }
 
 if (self.document) {
diff --git a/index.html b/index.html
index f025216..229d152 100644
--- a/index.html
+++ b/index.html
@@ -42,6 +42,12 @@ <h2>Step2</h2>
     </div>
   </div>
 
+  <h2>Step2.5</h2>
+  <p>Enter a sub folder name:</p>
+  <div>
+    <textarea id="pathPrefix" placeholder="Can be empty here"></textarea>
+  </div>
+
   <h2>Step3</h2>
   <div>
     <textarea id="txtUrls" placeholder="Upload Image And Paste URLs"></textarea>