diff --git a/.commitlintrc.json b/.commitlintrc.json
deleted file mode 100644
index 9f49e06..0000000
--- a/.commitlintrc.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "rules": {
-    "body-max-line-length": [0, "always"]
-  }
-}
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 3ee447e..0000000
--- a/.travis.yml
+++ /dev/null
@@ -1,48 +0,0 @@
-os: linux
-dist: bionic
-language: ruby
-rvm: 2.7.0
-
-addons:
-  apt:
-    packages:
-      - libcurl4-openssl-dev  # to avoid SSL error (for htmlproofer)
-
-# Overriding to drop the `--development` flag which requires the Gemfile.lock at build
-install: bundle install --jobs=3 --retry=3 --path=vendor/bundle
-
-before_script: git -C "$HOME" clone "$BUILDER_REPO" --depth=1 -q
-
-jobs:
-  include:
-    - stage: Upgrade
-      git:
-        depth: false  # for posts' lastmod
-      script: eval "$BUILD_CMD"
-    - stage: Starter
-      language: minimal
-      install: true   # skip install step
-      script: eval "$FLUSH_STARTER"
-    - stage: Docs
-      cache: bundler
-      git:
-        depth: false  # for posts' lastmod
-      script: eval "$DOCS_CMD"
-
-stages:
-  - name: Upgrade
-    if: branch = production
-  - name: Starter
-    if: branch = production
-  - name: Docs
-    if: branch = docs
-
-notifications:
-  email:
-    recipients:
-      - secure: "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"
-    on_success: never
-
-env:
-  global:
-    - NOKOGIRI_USE_SYSTEM_LIBRARIES=true # speeds up installation of html-proofer
diff --git a/.versionrc.json b/.versionrc.json
deleted file mode 100644
index 4b880d3..0000000
--- a/.versionrc.json
+++ /dev/null
@@ -1,20 +0,0 @@
-{
-  "skip": {
-    "commit": true,
-    "tag": true
-  },
-  "types": [
-    {
-      "type": "feat",
-      "section": "Features"
-    },
-    {
-      "type": "fix",
-      "section": "Bug Fixes"
-    },
-    {
-      "type": "perf",
-      "section": "Improvements"
-    }
-  ]
-}
diff --git a/_config.yml b/_config.yml
index db78e1b..fde0c4b 100644
--- a/_config.yml
+++ b/_config.yml
@@ -3,10 +3,6 @@
 # Import the theme
 theme: jekyll-theme-chirpy
 
-# Change the following value to '/PROJECT_NAME' ONLY IF your site type is GitHub Pages Project sites
-# and doesn't have a custom domain.
-baseurl: ''
-
 # The language of the webpage › http://www.lingoes.net/en/translator/langcode.htm
 # If it has the same name as one of the files in folder `_data/locales`, the layout language will also be changed,
 # otherwise, the layout language will use the default value of 'en'.
@@ -29,7 +25,7 @@ description: >-                        # used by seo meta and the atom feed
   A minimal, responsive, and powerful Jekyll theme for presenting professional writing.
 
 # fill in the protocol & hostname for your site, e.g., 'https://username.github.io'
-url: ''
+url: 'https://username.github.io'
 
 github:
   username: catusf             # change to your github username
@@ -203,10 +199,3 @@ jekyll-archives:
   permalinks:
     tag: /tags/:name/
     category: /categories/:name/
-
-plugins:
-  - jekyll-github-metadata
-  
-repository: catusf/catusf.github.io
-
-
diff --git a/_config.yml.bak b/_config.yml.bak
index 72c7780..1787a7e 100644
--- a/_config.yml.bak
+++ b/_config.yml.bak
@@ -80,10 +80,14 @@ theme_mode:   dark # [light|dark]
 # will be added to all image (site avatar & posts' images) paths starting with '/'
 #
 # e.g. 'https://cdn.com'
-img_cdn: '' # 'https://raw.githubusercontent.com/cotes2020/chirpy-images/main'
+img_cdn: "https://chirpy-img.netlify.app"
 
 # the avatar on sidebar, support local or CORS resources
-avatar: '/assets/img/avatar.png'
+avatar: "/commons/avatar.jpg"
+
+# The URL of the site-wide social preview image used in SEO `og:image` meta tag.
+# It can be overridden by a customized `page.image` in front matter.
+social_preview_image: # string, local or CORS resources
 
 # boolean type, the global switch for ToC in posts.
 toc: true
@@ -199,10 +203,3 @@ jekyll-archives:
   permalinks:
     tag: /tags/:name/
     category: /categories/:name/
-
-plugins:
-  - jekyll-github-metadata
-  
-repository: catusf/catusf.github.io
-
-
diff --git a/gulpfile.js/index.js b/gulpfile.js/index.js
deleted file mode 100644
index 14692fb..0000000
--- a/gulpfile.js/index.js
+++ /dev/null
@@ -1,10 +0,0 @@
-#!/usr/bin/env node
-
-"use strict";
-
-const js = require('./tasks/js');
-
-exports.default = js.build;
-
-/* keep-alive develop mode, without uglify */
-exports.dev = js.liveRebuild;
diff --git a/gulpfile.js/tasks/js.js b/gulpfile.js/tasks/js.js
deleted file mode 100644
index a1febb7..0000000
--- a/gulpfile.js/tasks/js.js
+++ /dev/null
@@ -1,102 +0,0 @@
-#!/usr/bin/env node
-
-"use strict";
-
-const { src, dest, watch, series, parallel} = require('gulp');
-
-const concat = require('gulp-concat');
-const rename = require("gulp-rename");
-const uglify = require('gulp-uglify');
-const insert = require('gulp-insert');
-const fs = require('fs');
-
-const JS_SRC = '_javascript';
-const JS_DEST = `assets/js/dist`;
-
-function concatJs(files, output) {
-  return src(files)
-    .pipe(concat(output))
-    .pipe(rename({ extname: '.min.js' }))
-    .pipe(dest(JS_DEST));
-}
-
-function minifyJs() {
-  return src(`${ JS_DEST }/*.js`)
-    .pipe(insert.prepend(fs.readFileSync(`${ JS_SRC }/copyright`, 'utf8')))
-    .pipe(uglify({output: {comments: /^!|@preserve|@license|@cc_on/i}}))
-    .pipe(dest(JS_DEST));
-}
-
-const commonsJs = () => {
-  return concatJs(`${JS_SRC}/commons/*.js`, 'commons');
-};
-
-const homeJs = () => {
-  return concatJs([
-      `${JS_SRC}/commons/*.js`,
-      `${JS_SRC}/utils/locale-datetime.js`
-    ],
-    'home'
-  );
-};
-
-const postJs = () => {
-  return concatJs([
-      `${JS_SRC}/commons/*.js`,
-      `${JS_SRC}/utils/img-extra.js`,
-      `${JS_SRC}/utils/locale-datetime.js`,
-      `${JS_SRC}/utils/checkbox.js`,
-      `${JS_SRC}/utils/clipboard.js`,
-      // 'smooth-scroll.js' must be called after ToC is ready
-      `${JS_SRC}/utils/smooth-scroll.js`
-    ], 'post'
-  );
-};
-
-const categoriesJs = () => {
-  return concatJs([
-      `${JS_SRC}/commons/*.js`,
-      `${JS_SRC}/utils/category-collapse.js`
-    ], 'categories'
-  );
-};
-
-const pageJs = () => {
-  return concatJs([
-      `${JS_SRC}/commons/*.js`,
-      `${JS_SRC}/utils/checkbox.js`,
-      `${JS_SRC}/utils/img-extra.js`,
-      `${JS_SRC}/utils/clipboard.js`,
-      `${JS_SRC}/utils/smooth-scroll.js`
-    ], 'page'
-  );
-};
-
-const miscJs = () => {
-  return concatJs([
-      `${JS_SRC}/commons/*.js`,
-      `${JS_SRC}/utils/locale-datetime.js`
-    ], 'misc'
-  );
-};
-
-// GA pageviews report
-const pvreportJs = () => {
-  return concatJs(`${JS_SRC}/utils/pageviews.js`, 'pvreport');
-};
-
-const buildJs = parallel(
-  commonsJs, homeJs, postJs, categoriesJs, pageJs, miscJs, pvreportJs);
-
-exports.build = series(buildJs, minifyJs);
-
-exports.liveRebuild = () => {
-  buildJs();
-
-  watch([
-      `${ JS_SRC }/commons/*.js`,
-      `${ JS_SRC }/utils/*.js`
-    ],
-    buildJs
-  );
-};