fix: code highlight in dark mode (#702)

web/src/less/code-highlight.less

@@ -0,0 +1,7 @@
+html.dark {
+  @import (less) "highlight.js/styles/atom-one-dark.css";
+}
+
+html:not(.dark) {
+  @import (less) "highlight.js/styles/github.css";
+}

web/src/main.tsx

@@ -11,7 +11,7 @@ import "dayjs/locale/zh";
 import "dayjs/locale/fr";
 import "dayjs/locale/vi";
 import theme from "./theme";
-import "highlight.js/styles/github.css";
+import "./less/code-highlight.less";
 import "./css/global.css";
 import "./css/tailwind.css";