update bookdowm doc
diff --git a/docs/bookdown/bookdown_example.tex b/docs/bookdown/bookdown_example.tex
index cc2ec9b..2a320f1 100644
--- a/docs/bookdown/bookdown_example.tex
+++ b/docs/bookdown/bookdown_example.tex
@@ -125,7 +125,7 @@
   \postauthor{\par}
       \predate{\centering\large\emph}
   \postdate{\par}
-    \date{2018-10-03}
+    \date{2018-10-04}
 
 \usepackage{booktabs}
 \usepackage{booktabs}
@@ -279,7 +279,6 @@
 \begin{Shaded}
 \begin{Highlighting}[]
 \KeywordTok{library}\NormalTok{(kableExtra)}
-\KeywordTok{options}\NormalTok{(}\DataTypeTok{kableExtra.html.bsTable =}\NormalTok{ T)}
 
 \NormalTok{mtcars[}\DecValTok{1}\OperatorTok{:}\DecValTok{5}\NormalTok{, }\DecValTok{1}\OperatorTok{:}\DecValTok{5}\NormalTok{] }\OperatorTok{%>%}
 \StringTok{  }\KeywordTok{kable}\NormalTok{(}\DataTypeTok{booktabs =}\NormalTok{ T) }\OperatorTok{%>%}\StringTok{ }