diff --git a/en/book.toml b/en/book.toml
index ab6b7ce..43b5e70 100644
--- a/en/book.toml
+++ b/en/book.toml
@@ -13,7 +13,7 @@ enable = true
 level = 1
 
 [output.html]
-additional-css = ["theme/style2.css"]
+additional-css = ["theme/style.css"]
 additional-js = ["assets/custom.js"]
 git-repository-url = "https://github.com/sunface/rust-by-practice"
 edit-url-template = "https://github.com/sunface/rust-by-practice/edit/master/en/{path}"
diff --git a/en/theme/style2.css b/en/theme/style.css
similarity index 85%
rename from en/theme/style2.css
rename to en/theme/style.css
index 16b7e03..f1879d3 100644
--- a/en/theme/style2.css
+++ b/en/theme/style.css
@@ -50,4 +50,16 @@
     overflow: hidden;
     padding: 10px 0;
     color: gray;
+}
+
+/* 修改章节目录的间距 */
+.chapter li.chapter-item {
+    /* 没有文件时的文字颜色 */
+    color: #939da3;
+    margin-top: 1.2rem;
+}
+
+/* 修改滚动条宽度 */
+::-webkit-scrollbar {
+    width: 7px;
 }
\ No newline at end of file
diff --git a/zh-CN/book.toml b/zh-CN/book.toml
index 5b5b44c..df59d8e 100644
--- a/zh-CN/book.toml
+++ b/zh-CN/book.toml
@@ -13,7 +13,7 @@ enable = true
 level = 1
 
 [output.html]
-additional-css = ["theme/style2.css"]
+additional-css = ["theme/style.css"]
 additional-js = ["assets/custom.js"]
 git-repository-url = "https://github.com/sunface/rust-by-practice"
 edit-url-template = "https://github.com/sunface/rust-by-practice/edit/master/zh-CN/{path}"
diff --git a/zh-CN/theme/style2.css b/zh-CN/theme/style.css
similarity index 85%
rename from zh-CN/theme/style2.css
rename to zh-CN/theme/style.css
index 16b7e03..f1879d3 100644
--- a/zh-CN/theme/style2.css
+++ b/zh-CN/theme/style.css
@@ -50,4 +50,16 @@
     overflow: hidden;
     padding: 10px 0;
     color: gray;
+}
+
+/* 修改章节目录的间距 */
+.chapter li.chapter-item {
+    /* 没有文件时的文字颜色 */
+    color: #939da3;
+    margin-top: 1.2rem;
+}
+
+/* 修改滚动条宽度 */
+::-webkit-scrollbar {
+    width: 7px;
 }
\ No newline at end of file