improvement for multiple weight fonts on strong, etc

- `strong`, `dfn` and `b`
- based on: necolas/normalize.css#342

sass/han/hyu/_semantics.sass

@@ -89,6 +89,32 @@ em
 em:lang(ja)
   +hyu-text-emphasis( over )
 
+/**
+ * Importance, definitions and Keywords
+ * (重點、術語、關鍵字)
+ */
+
+// * Improvement for multiple weight fonts.
+// * See: https://github.com/necolas/normalize.css/pull/342
+// *
+
+strong,
+dfn:lang(zh),
+dfn:lang(ja),
+b
+  font-weight: inherit
+
+strong,
+dfn:lang(zh),
+dfn:lang(ja),
+b
+  font-weight: bolder
+
+dfn
+  &:lang(zh),
+  &:lang(ja)
+    font-style: inherit
+
 /**
  * Cites and quotes
  * (來源、引用)
@@ -121,16 +147,6 @@ q
   &:lang(ja):after
     content: none
 
-/**
- * Definitions
- * (術語)
- */
-dfn
-  &:lang(zh),
-  &:lang(ja)
-    font-style: inherit
-    font-weight: bold
-
 /**
  * Code, user input, computer output, preformatted text
  * (代碼、輸入鍵、計算機輸出示例、格式預處理文字)