refactor: Reorganize CSS styles and improve structure

- Move box shadow and ellipsis styles to redefine-theme.styl
- Relocate page title header styles to page.styl
- Remove unused styles from basic.styl
- Clean up style.styl by removing redundant code

source/css/common/basic.styl

@@ -159,3 +159,9 @@ button
 // ======================================================================
 .clear
   clear both
+
+// ======================================================================
+// text
+// ======================================================================
+
+

source/css/common/redefine-theme.styl

@@ -43,3 +43,23 @@ redefine-container(isTransform, scaleX, scaleY, padding, marginBottomValue)
   +redefine-mobile()
     padding: padding - 8
     border-radius: $redefine-border-radius-large
+
+
+.redefine-box-shadow
+  box-shadow var(--redefine-box-shadow)
+
+.redefine-box-shadow-flat
+  box-shadow var(--redefine-box-shadow-flat)
+
+@media (min-width: 640px)
+  .redefine-box-shadow:hover
+    box-shadow var(--redefine-box-shadow-hover)
+
+  .redefine-box-shadow-flat:hover
+    box-shadow var(--redefine-box-shadow)
+
+.ellipsis
+  overflow hidden
+  text-overflow ellipsis
+  white-space nowrap
+  width 100%

source/css/layout/page.styl

@@ -1,5 +1,12 @@
 @require '../common/variables'
 
+.page-title-header
+  font-size 3.2rem
+  line-height 1
+  font-weight bold
+  color var(--second-text-color)
+  margin 6px 0 36px 0
+
 .page-container
   position relative
   box-sizing border-box

source/css/style.styl

@@ -22,30 +22,4 @@
 @require 'layout/tag-content.styl'
 
 if (hexo-config('home.sidebar.enable') == true)
-  @require 'layout/home-sidebar.styl'
-
-.page-title-header
-  font-size 3.2rem
-  line-height 1
-  font-weight bold
-  color var(--second-text-color)
-  margin 6px 0 36px 0
-
-.redefine-box-shadow
-  box-shadow var(--redefine-box-shadow)
-
-.redefine-box-shadow-flat
-  box-shadow var(--redefine-box-shadow-flat)
-
-@media (min-width: 640px)
-  .redefine-box-shadow:hover
-    box-shadow var(--redefine-box-shadow-hover)
-
-  .redefine-box-shadow-flat:hover
-    box-shadow var(--redefine-box-shadow)
-
-.ellipsis
-  overflow hidden
-  text-overflow ellipsis
-  white-space nowrap
-  width 100%
+  @require 'layout/home-sidebar.styl'