优化

doc/demo.css

@@ -232,6 +232,15 @@ code.inline {
     display: block;
 }
 
+/* Reduce background paint cost while a layer is open */
+.layer-open .box-header,
+.layer-open .code-view,
+.layer-open .html-view,
+.layer-open .css-view,
+.layer-open .feature-desc {
+    visibility: hidden;
+}
+
 /* Syntax Highlighting */
 .kwd { color: #c678dd; }
 .str { color: #98c379; }