修复iOS上代码字体大小错乱的问题

source/css/_common/highlight.styl

@@ -1,8 +1,6 @@
 article.md .highlight
   margin: 1rem 0
   border-radius: $border-block
-  -webkit-font-smoothing: auto
-  -moz-osx-font-smoothing: auto
   overflow: hidden
   background: var(--block)
   border: 1px solid var(--block-border)

source/css/_layout/md.styl

@@ -70,6 +70,8 @@ article.md p
 article.md code
   -webkit-font-smoothing: auto
   -moz-osx-font-smoothing: auto
+  -webkit-text-size-adjust: 100%
+  -ms-text-size-adjust: 100%
   color: var(--text-code)
   font-family: $ff-code
   word-break: break-all
@@ -77,7 +79,11 @@ article.md code
   background: var(--block)
   padding: .2em .4em
   border-radius: 2px
-  // border: 1px solid var(--block-border)
+article.md pre
+  -webkit-font-smoothing: auto
+  -moz-osx-font-smoothing: auto
+  -webkit-text-size-adjust: 100%
+  -ms-text-size-adjust: 100%
 
 // div
 article.md>div