diff --git a/README.md b/README.md
index b3ab207..c3a8e1a 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,8 @@
 # The IT things I learned
 
 
-
-
 It helps me:
 
 * Master knowledge
-* Summarize the things I know and learned
-* Prepare interview
-* Share the good things to you
+* Look back all the things I've heard about
+* Prepare interviews
diff --git a/assets/css/custom.css b/assets/css/custom.css
new file mode 100644
index 0000000..1b7221c
--- /dev/null
+++ b/assets/css/custom.css
@@ -0,0 +1,818 @@
+@import url("https://fonts.googleapis.com/css?family=Roboto+Mono|Source+Sans+Pro:300,400,600");
+* {
+  -webkit-font-smoothing: antialiased;
+  -webkit-overflow-scrolling: touch;
+  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
+  -webkit-text-size-adjust: none;
+  -webkit-touch-callout: none;
+  box-sizing: border-box;
+}
+body:not(.ready) {
+  overflow: hidden;
+}
+body:not(.ready) .app-nav,
+body:not(.ready) > nav,
+body:not(.ready) [data-cloak] {
+  display: none;
+}
+div#app {
+  font-size: 30px;
+  font-weight: lighter;
+  margin: 40vh auto;
+  text-align: center;
+}
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+  content: "Loading...";
+}
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+  height: 1.2rem;
+  vertical-align: middle;
+}
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+  height: 2px;
+  left: 0;
+  position: fixed;
+  right: 0;
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+  transition: width 0.2s, opacity 0.4s;
+  width: 0;
+  z-index: 5;
+}
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+}
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+  font-weight: 700;
+}
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+  height: 100%;
+}
+body {
+  -moz-osx-font-smoothing: grayscale;
+  -webkit-font-smoothing: antialiased;
+  color: #34495e;
+  font-family: -apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;
+  font-size: 16px;
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+  margin: 0;
+  overflow-x: hidden;
+}
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+}
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+  opacity: 0.6;
+}
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+  font-size: 12px !important;
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+  padding: 3px 5px;
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+}
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+}
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+}
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+}
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+}
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+}
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+  margin: 0 1rem;
+  padding: 5px 0;
+  position: relative;
+}
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+  border: 1px solid #ddd;
+  border-bottom-color: #ccc;
+  border-radius: 4px;
+  box-sizing: border-box;
+  display: none;
+  max-height: calc(100vh - 61px);
+  overflow-y: auto;
+  padding: 10px 0;
+  position: absolute;
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+}
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+}
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+  margin: 0;
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+}
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+}
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+}
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+  border-bottom: 0;
+  position: fixed;
+  right: 0;
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+}
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+  animation: a 0.56s ease-in-out;
+}
+.github-corner svg {
+  color: #fff;
+  fill: var(--theme-color, #42b983);
+  height: 80px;
+  width: 80px;
+}
+main {
+  display: block;
+  position: relative;
+  width: 100vw;
+  height: 100%;
+  z-index: 0;
+}
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+}
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+  text-decoration: none;
+  transition: all 0.3s;
+}
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+  color: #42b983;
+}
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+}
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+  border-right: 1px solid rgba(0, 0, 0, 0.07);
+  overflow-y: auto;
+  padding: 40px 0 0;
+  position: absolute;
+  top: 0;
+  bottom: 0;
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+}
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+  font-size: 1.5rem;
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+}
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+  position: static;
+}
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+}
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+}
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+}
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+  bottom: 0;
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+  text-align: center;
+  transition: opacity 0.3s;
+  width: 284px;
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+}
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+}
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+  background-color: var(--theme-color, #42b983);
+  display: block;
+  margin-bottom: 4px;
+  width: 16px;
+  height: 2px;
+}
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+body.sticky .sidebar-toggle {
+  position: fixed;
+}
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+  padding-top: 60px;
+  position: absolute;
+  top: 0;
+  right: 0;
+  bottom: 0;
+  left: 300px;
+  transition: left 0.25s ease;
+}
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+  margin: 0 auto;
+  max-width: 960px;
+  padding: 30px 15px 40px;
+  position: relative;
+}
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+  box-sizing: border-box;
+}
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+  margin-top: 0 !important;
+}
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+  border: none;
+  border-bottom: 1px solid #eee;
+  margin: 2em 0;
+}
+.markdown-section iframe {
+  border: 1px solid #eee;
+}
+.markdown-section table {
+  border-collapse: collapse;
+  border-spacing: 0;
+  display: block;
+  margin-bottom: 1rem;
+  overflow: auto;
+  width: 100%;
+}
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+  font-weight: 700;
+}
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+.markdown-section th {
+  border: 1px solid #ddd;
+  padding: 6px 13px;
+}
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+  border-top: 1px solid #ccc;
+}
+.markdown-section p.tip,
+.markdown-section tr:nth-child(2n) {
+  background-color: #f8f8f8;
+}
+.markdown-section p.tip {
+  border-bottom-right-radius: 2px;
+  border-left: 4px solid #f66;
+  border-top-right-radius: 2px;
+  margin: 2em 0;
+  padding: 12px 24px 12px 30px;
+  position: relative;
+}
+.markdown-section p.tip:before {
+  background-color: #f66;
+  border-radius: 100%;
+  color: #fff;
+  content: "!";
+  font-family: Dosis, Source Sans Pro, Helvetica Neue, Arial, sans-serif;
+  font-size: 14px;
+  font-weight: 700;
+  left: -12px;
+  line-height: 20px;
+  position: absolute;
+  height: 20px;
+  width: 20px;
+  text-align: center;
+  top: 14px;
+}
+.markdown-section p.tip code {
+  background-color: #efefef;
+}
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+  color: #34495e;
+}
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+  background: rgba(66, 185, 131, 0.1);
+  border-radius: 2px;
+  padding: 1rem;
+}
+body.close .sidebar {
+  transform: translateX(-300px);
+}
+body.close .sidebar-toggle {
+  width: auto;
+}
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+  left: 0;
+}
+@media print {
+  .app-nav,
+  .github-corner,
+  .sidebar,
+  .sidebar-toggle {
+    display: none;
+  }
+}
+@media screen and (max-width: 768px) {
+  .github-corner,
+  .sidebar,
+  .sidebar-toggle {
+    position: fixed;
+  }
+  .app-nav {
+    margin-top: 16px;
+  }
+  .app-nav li ul {
+    top: 30px;
+  }
+  main {
+    height: auto;
+    overflow-x: hidden;
+  }
+  .sidebar {
+    left: -300px;
+    transition: transform 0.25s ease-out;
+  }
+  .content {
+    left: 0;
+    max-width: 100vw;
+    position: static;
+    padding-top: 20px;
+    transition: transform 0.25s ease;
+  }
+  .app-nav,
+  .github-corner {
+    transition: transform 0.25s ease-out;
+  }
+  .sidebar-toggle {
+    background-color: transparent;
+    width: auto;
+    padding: 30px 30px 10px 10px;
+  }
+  body.close .sidebar {
+    transform: translateX(300px);
+  }
+  body.close .sidebar-toggle {
+    background-color: hsla(0, 0%, 100%, 0.8);
+    transition: background-color 1s;
+    width: 284px;
+    padding: 10px;
+  }
+  body.close .content {
+    transform: translateX(300px);
+  }
+  body.close .app-nav,
+  body.close .github-corner {
+    display: none;
+  }
+  .github-corner:hover .octo-arm {
+    animation: none;
+  }
+  .github-corner .octo-arm {
+    animation: a 0.56s ease-in-out;
+  }
+}
+@keyframes a {
+  0%,
+  to {
+    transform: rotate(0);
+  }
+  20%,
+  60% {
+    transform: rotate(-25deg);
+  }
+  40%,
+  80% {
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+  }
+}
+section.cover {
+  -ms-flex-align: center;
+  align-items: center;
+  background-position: 50%;
+  background-repeat: no-repeat;
+  background-size: cover;
+  height: 100vh;
+  display: none;
+}
+section.cover.show {
+  display: -ms-flexbox;
+  display: flex;
+}
+section.cover.has-mask .mask {
+  background-color: #fff;
+  opacity: 0.8;
+  position: absolute;
+  top: 0;
+  height: 100%;
+  width: 100%;
+}
+section.cover .cover-main {
+  -ms-flex: 1;
+  flex: 1;
+  margin: -20px 16px 0;
+  text-align: center;
+  z-index: 1;
+}
+section.cover a {
+  color: inherit;
+}
+section.cover a,
+section.cover a:hover {
+  text-decoration: none;
+}
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+  line-height: 1.5rem;
+  margin: 1em 0;
+}
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+  color: inherit;
+  font-size: 2.5rem;
+  font-weight: 300;
+  margin: 0.625rem 0 2.5rem;
+  position: relative;
+  text-align: center;
+}
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+}
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+  font-size: 1rem;
+  position: absolute;
+}
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+  text-align: center;
+}
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+  list-style-type: none;
+  margin: 1em auto;
+  max-width: 500px;
+  padding: 0;
+}
+section.cover .cover-main > p:last-child a {
+  border: 1px solid var(--theme-color, #42b983);
+  border-radius: 2rem;
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+  padding: 0.75em 2rem;
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+  transition: all 0.15s ease;
+}
+section.cover .cover-main > p:last-child a:last-child {
+  background-color: var(--theme-color, #42b983);
+  color: #fff;
+}
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+  color: inherit;
+  opacity: 0.8;
+}
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+  color: inherit;
+}
+section.cover blockquote > p > a {
+  border-bottom: 2px solid var(--theme-color, #42b983);
+  transition: color 0.3s;
+}
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+}
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+}
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+}
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+  font-size: 14px;
+  font-weight: 400;
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+}
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+}
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+  font-weight: 600;
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+  font-weight: 600;
+}
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+  margin: 0 0 1rem;
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+}
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+}
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+}
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+  margin: 45px 0 0.8rem;
+}
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+  margin: 40px 0 0.6rem;
+}
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+}
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+  word-spacing: 0.05rem;
+}
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+  padding-left: 1.5rem;
+}
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+  border-left: 4px solid var(--theme-color, #42b983);
+  color: #858585;
+  margin: 2em 0;
+  padding-left: 20px;
+}
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+  font-weight: 600;
+  margin-left: 0;
+}
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+  margin: 1em 0;
+}
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+  color: #7f8c8d;
+}
+.markdown-section code {
+  border-radius: 2px;
+  color: #e96900;
+  font-size: 0.8rem;
+  margin: 0 2px;
+  padding: 3px 5px;
+  white-space: pre-wrap;
+}
+.markdown-section code,
+.markdown-section pre {
+  background-color: #f8f8f8;
+  font-family: Roboto Mono, Monaco, courier, monospace;
+}
+.markdown-section pre {
+  -moz-osx-font-smoothing: initial;
+  -webkit-font-smoothing: initial;
+  line-height: 1.5rem;
+  margin: 1.2em 0;
+  overflow: auto;
+  padding: 0 1.4rem;
+  position: relative;
+  word-wrap: normal;
+}
+.token.cdata,
+.token.comment,
+.token.doctype,
+.token.prolog {
+  color: #8e908c;
+}
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+}
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+  color: #c76b29;
+}
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+  color: #525252;
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+  color: #c08b30;
+}
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+  color: #2973b7;
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+  color: var(--theme-color, #42b983);
+}
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+  color: #2973b7;
+}
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+.style .token.string,
+.token.entity,
+.token.url {
+  color: #22a2c9;
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+.token.attr-value,
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+.token.directive,
+.token.unit {
+  color: var(--theme-color, #42b983);
+}
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+}
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+.token.regex,
+.token.statement {
+  color: #22a2c9;
+}
+.token.placeholder,
+.token.variable {
+  color: #3d8fd1;
+}
+.token.deleted {
+  text-decoration: line-through;
+}
+.token.inserted {
+  border-bottom: 1px dotted #202746;
+  text-decoration: none;
+}
+.token.italic {
+  font-style: italic;
+}
+.token.bold,
+.token.important {
+  font-weight: 700;
+}
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+  color: #c94922;
+}
+.token.entity {
+  cursor: help;
+}
+.markdown-section pre > code {
+  -moz-osx-font-smoothing: initial;
+  -webkit-font-smoothing: initial;
+  background-color: #f8f8f8;
+  border-radius: 2px;
+  color: #525252;
+  display: block;
+  font-family: Roboto Mono, Monaco, courier, monospace;
+  font-size: 0.8rem;
+  line-height: inherit;
+  margin: 0 2px;
+  max-width: inherit;
+  overflow: inherit;
+  padding: 2.2em 5px;
+  white-space: inherit;
+}
+.markdown-section code:after,
+.markdown-section code:before {
+  letter-spacing: 0.05rem;
+}
+code .token {
+  -moz-osx-font-smoothing: initial;
+  -webkit-font-smoothing: initial;
+  min-height: 1.5rem;
+}
+pre:after {
+  color: #ccc;
+  content: attr(data-lang);
+  font-size: 0.6rem;
+  font-weight: 600;
+  height: 15px;
+  line-height: 15px;
+  padding: 5px 10px 0;
+  position: absolute;
+  right: 0;
+  text-align: right;
+  top: 0;
+}
diff --git a/categories/devops.md b/categories/devops.md
index 6016e34..acc7675 100644
--- a/categories/devops.md
+++ b/categories/devops.md
@@ -48,7 +48,9 @@ Chef enables you to manage and scale cloud infrastructure with no downtime or in
 Chef running a `chef-client` on each node to be a runner to install applications on remote server. The client can use both `pull` and `push` modes to to communication.
 
 More:
-* Chef vs ansible: <https://www.chef.io/ansible/>
+
+- Chef vs ansible: <https://www.chef.io/ansible/>
+
 ### Ansible
 
 #### What is Ansible
diff --git a/index.html b/index.html
index e35223e..778457b 100644
--- a/index.html
+++ b/index.html
@@ -9,10 +9,10 @@
   <meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
   <!-- <link rel="stylesheet" href="//unpkg.com/docsify/lib/themes/vue.css"> -->
   <!-- Theme: Defaults -->
-  <link rel="stylesheet" href="https://unpkg.com/docsify-themeable/dist/css/theme-defaults.css">
+  <!-- <link rel="stylesheet" href="https://unpkg.com/docsify-themeable/dist/css/theme-defaults.css"> -->
   <link rel="stylesheet" href="https://unpkg.com/prism-themes/themes/prism-ghcolors.css">
   <link rel="stylesheet" href="//cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.css">
-
+  <link rel="stylesheet" href="/assets/css/custom.css">
 
   <style>
     :root {