diff --git a/index.html b/index.html
index 45f31e3..6661d56 100644
--- a/index.html
+++ b/index.html
@@ -11,6 +11,8 @@
   <link rel="stylesheet" href="https://use.fontawesome.com/releases/v5.15.4/css/all.css">
 
   <link rel="manifest" href="manifest.json" />
+  <meta name="theme-color" content="#effaf5">
+  <link rel="apple-touch-icon" href="icon/icon.png">
 
   <link rel="stylesheet" href="css/style.css">
 
diff --git a/js/app.js b/js/app.js
index 8167bfb..629584f 100644
--- a/js/app.js
+++ b/js/app.js
@@ -53,6 +53,19 @@ document.addEventListener('DOMContentLoaded', () => {
   i18n_init()
 })
 
+// service worker
+if ('serviceWorker' in navigator) {
+  navigator.serviceWorker
+    .register('sw.js')
+    .then((registration) => {
+      console.log('sw registered!')
+      console.log(registration)
+    })
+    .catch((error) => {
+      console.log('sw error: ' + error)
+    })
+}
+
 // html changed service
 function html_changed() {
   i18n_refresh()
@@ -296,7 +309,7 @@ function populateVoiceList() {
 function generate_now_weather_speech_script(nowstate) {
   speech_script[
     'zh-TW'
-  ] = `今天天氣${nowstate.CI}、${nowstate.Wx}，最高溫度維${nowstate.MaxT}度C，最低溫度維${nowstate.MinT}度C，降雨機率${nowstate.PoP}趴。`
+  ] = `今日${cwb_location_select_value}天氣${nowstate.CI}、${nowstate.Wx}，最高溫度維${nowstate.MaxT}度C，最低溫度維${nowstate.MinT}度C，降雨機率${nowstate.PoP}趴。`
   speech_script[
     'en-US'
   ] = `Today's High Temperature is ${nowstate.MaxT} Celsius, Low Temperature is${nowstate.MinT}Celsius, probability of precipitation is ${nowstate.PoP} percent`
diff --git a/manifest.json b/manifest.json
index 484e3b8..2d54eb6 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1,13 +1,13 @@
 {
-  "background_color": "#ffffff",
   "dir": "ltr",
   "display": "standalone",
   "name": "alsoweather",
   "orientation": "any",
-  "scope": "/alsoweather/",
+  "scope": "./",
   "short_name": "alsoweather",
-  "start_url": "/alsoweather/",
-  "theme_color": "#ffffff",
+  "start_url": "./",
+  "theme_color": "#CCCC99",
+  "background_color": "#ffffff",
   "icons": [
     {
       "src": "icon/icon.png",
diff --git a/sw.js b/sw.js
new file mode 100644
index 0000000..0b0203c
--- /dev/null
+++ b/sw.js
@@ -0,0 +1,23 @@
+self.addEventListener('install', (e) => {
+  e.waitUntil(
+    caches.open('static').then((cache) => {
+      return cache.addAll([
+        './',
+        './css/bulma.min.css',
+        './css/style.css',
+        './js/chart.min.js',
+        './js/i18n.js',
+        './js/my-chart.js',
+        './icon/icon.png',
+      ])
+    })
+  )
+})
+
+self.addEventListener('fetch', (e) => {
+  e.respondWith(
+    caches.match(e.request).then((response) => {
+      return response || fetch(e.request)
+    })
+  )
+})