From ece4171ae40e0956c9d69e317fee1f96c427b113 Mon Sep 17 00:00:00 2001
From: Ryan P Kilby <rpkilby@ncsu.edu>
Date: Tue, 30 Jan 2018 03:08:06 -0500
Subject: [PATCH] Replace `background-attachment: fixed` in docs (#5777)

Fixed backgrounds have performance issues on large displays.
---
 docs_theme/css/default.css | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/docs_theme/css/default.css b/docs_theme/css/default.css
index a0a286b22..bb17a3a11 100644
--- a/docs_theme/css/default.css
+++ b/docs_theme/css/default.css
@@ -160,9 +160,19 @@ body, .navbar .navbar-inner .container-fluid{
   margin: 0 auto;
 }
 
-body{
-  background: url("../img/grid.png") repeat-x;
-  background-attachment: fixed;
+/* Replacement for `body { background-attachment: fixed; }`, which
+   has performance issues when scrolling on large displays. */
+body::before {
+    content: ' ';
+    position: fixed;
+    width: 100%;
+    height: 100%;
+    top: 0;
+    left: 0;
+    background-color: #f8f8f8;
+    background: url(../img/grid.png) repeat-x;
+    will-change: transform;
+    z-index: -1;
 }