address https://github.com/loikein/hugo-tufte/issues/4

assets/scss/components/code-highlight.scss

@@ -1,63 +1,75 @@
 $ht-code-border-radius: .4em;
 .highlight {
-    width: 55%;
+    width: 50%;
     overflow-x: scroll;
-    border-radius: $ht-code-border-radius;
+    // border-radius: $ht-code-border-radius;
+    margin-top: 1em;
+    margin-bottom: 1em;
+    margin-right: 2.5%;
+    margin-left: 2.5%;
+    -ms-overflow-style: none;
+    scrollbar-width: none;
+
+    &::-webkit-scrollbar {
+        display: none;
+    }
+
+    code {
+        font-size: 1rem;
+        display: block;
+    }
+
+    &>.chroma {
+        margin: 0;
+    }
+
+    &>.chroma .hl {
+        // border-radius: $ht-code-border-radius / 2;
+        display: block;
+
+        &::before{
+            content: "> ";
+            position: absolute;
+            left: 0;
+            color: #111;
+        }
+    }
 
     &>div.chroma>table.lntable{
-        margin: $ht-code-border-radius 0 $ht-code-border-radius 0;
+        overflow: initial;
+        // margin: $ht-code-border-radius 0 $ht-code-border-radius 0;
         & td:first-of-type {
             & span:not(& span>span) {
                 padding: 0 .75em 0 .5em;
             }
         }
-    }
-    &>.chroma>code {
 
+        pre {
+            margin-block-start: 0.5em;
+            margin-block-end: 0.5em;
+        }
+    }
+
+    &>.chroma>code {
         width: max-content;
         margin-top: .5em;
         margin-bottom: .5em;
         margin-left: .5em;
+
         &>span.hl{
             margin-left: -.5em;
             padding-left: .5em;
         }
     }
-
-    .chroma .hl {
-        // border-radius: $ht-code-border-radius / 2;
-        display: block;
 }
 
-    &::-webkit-scrollbar {
-        border-radius: $ht-code-border-radius;
-        width: 10px;
-        height: 1rem;
-    }
-    &::-webkit-scrollbar-thumb {
-        border-radius: $ht-code-border-radius;
-    }
-}
 
 @media screen and (max-width: 760px) {
-    .highlight {
+    .highlight .chroma {
         width: 90%;
     }
 }
 
-.highlight .lntable {
-    overflow: initial;
-}
-
-.highlight pre {
-    margin: 0;
-}
-
-.highlight pre code {
-    display: block;
-    font-size: 1rem;
-}
-
 // fix #48 => https://github.com/slashformotion/hugo-tufte/issues/48
 ul>li>div.highlight {
     width: 100%;

assets/scss/syntax/highlight-dark.scss

@@ -1,12 +1,3 @@
 $ht-code-bgcolor: #282a36;
 
 @import "syntax-dark.scss";
-
-.highlight {
-    &::-webkit-scrollbar {
-        background: $ht-code-bgcolor;
-    }
-    &::-webkit-scrollbar-thumb {
-        background: scale-color($ht-code-bgcolor, $lightness: 23%, $saturation: -40%);
-    }
-}

assets/scss/syntax/highlight-light.scss

@@ -1,12 +1,3 @@
 $ht-code-bgcolor: #dde2ff;
 
 @import "syntax-light.scss";
-
-.highlight {
-    &::-webkit-scrollbar {
-        background: $ht-code-bgcolor;
-    }
-    &::-webkit-scrollbar-thumb {
-        background: scale-color($ht-code-bgcolor, $lightness: -13%, $saturation: -80%);
-    }
-}

assets/scss/syntax/syntax-dark.scss

@@ -12,6 +12,7 @@
 * @author Zeno Rocha <hi@zenorocha.com>
 */
 
+.highlight .lnt { color: #6272a4 } /* line number */
 .highlight .hl { background-color: scale-color($ht-code-bgcolor, $lightness: 32%, $saturation: -40%) }
 .highlight  { background: $ht-code-bgcolor; color: #f8f8f2 }
 .highlight .c { color: #6272a4 } /* Comment */

assets/scss/syntax/syntax-light.scss

@@ -1,5 +1,6 @@
-.highlight .hl { background-color: #ffffd4 }
+// .highlight .hl { background-color: #ffffd4 }
-.highlight  { background: $ht-code-bgcolor;}
+// .highlight  { background: $ht-code-bgcolor;}
+.highlight .lnt { color: #6a737d } /* line number */
 .highlight .c { color: #6a737d } /* Comment */
 .highlight .err {  } /* Error */
 .highlight .k { color: #d73a49 } /* Keyword */

assets/scss/vendor/tufte.scss

@@ -347,6 +347,7 @@ h3 .code {
 }
 
 pre.code {
+    font-size: 0.9rem;
     width: 52.5%;
     padding-left: 2.5%;
     overflow-x: scroll;