docs: improve code comments (#1911)

src/styles/element-ui.scss

@@ -1,4 +1,4 @@
-//覆盖一些element-ui样式
+// cover some element-ui styles
 
 .el-breadcrumb__inner,
 .el-breadcrumb__inner a {

src/styles/index.scss

@@ -96,14 +96,18 @@ div:focus {
   }
 }
 
-code {
+aside {
   background: #eef1f6;
-  padding: 15px 16px;
+  padding: 8px 24px;
   margin-bottom: 20px;
+  border-radius: 2px;
   display: block;
-  line-height: 36px;
-  font-size: 15px;
-  font-family: "Source Sans Pro", "Helvetica Neue", Arial, sans-serif;
+  line-height: 32px;
+  font-size: 16px;
+  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
+  color: #2c3e50;
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
 
   a {
     color: #337ab7;
@@ -115,20 +119,6 @@ code {
   }
 }
 
-.warn-content {
-  background: rgba(66, 185, 131, .1);
-  border-radius: 2px;
-  padding: 16px;
-  padding: 1rem;
-  line-height: 1.6rem;
-  word-spacing: .05rem;
-
-  a {
-    color: #42b983;
-    font-weight: 600;
-  }
-}
-
 //main-container全局样式
 .app-container {
   padding: 20px;

src/styles/sidebar.scss

@@ -1,6 +1,5 @@
 #app {
 
-  // 主体区域 Main container
   .main-container {
     min-height: 100%;
     transition: margin-left .28s;
@@ -8,7 +7,6 @@
     position: relative;
   }
 
-  // 侧边栏 Sidebar container
   .sidebar-container {
     transition: width 0.28s;
     width: $sideBarWidth !important;
@@ -22,7 +20,7 @@
     z-index: 1001;
     overflow: hidden;
 
-    //reset element-ui css
+    // reset element-ui css
     .horizontal-collapse-transition {
       transition: 0s width ease-in-out, 0s padding-left ease-in-out, 0s padding-right ease-in-out;
     }
@@ -149,7 +147,7 @@
     min-width: $sideBarWidth !important;
   }
 
-  // 适配移动端, Mobile responsive
+  // mobile responsive
   .mobile {
     .main-container {
       margin-left: 0px;

src/styles/transition.scss

@@ -1,6 +1,6 @@
-//global transition css
+// global transition css
 
-/*fade*/
+/* fade */
 .fade-enter-active,
 .fade-leave-active {
   transition: opacity 0.28s;
@@ -11,7 +11,7 @@
   opacity: 0;
 }
 
-/*fade-transform*/
+/* fade-transform */
 .fade-transform-leave-active,
 .fade-transform-enter-active {
   transition: all .5s;
@@ -27,7 +27,7 @@
   transform: translateX(30px);
 }
 
-/*breadcrumb transition*/
+/* breadcrumb transition */
 .breadcrumb-enter-active,
 .breadcrumb-leave-active {
   transition: all .5s;

src/styles/variables.scss

@@ -8,10 +8,10 @@ $tiffany: #4AB7BD;
 $yellow:#FEC171;
 $panGreen: #30B08F;
 
-//sidebar
+// sidebar
 $menuText:#bfcbd9;
 $menuActiveText:#409EFF;
-$subMenuActiveText:#f4f4f5; //https://github.com/ElemeFE/element/issues/12951
+$subMenuActiveText:#f4f4f5; // https://github.com/ElemeFE/element/issues/12951
 
 $menuBg:#304156;
 $menuHover:#263445;