[llvm] [Docs] Fix large vertical space at top of pages (PR #81599)

[J. Ryan Stinnett via llvm-commits]

https://github.com/jryans created https://github.com/llvm/llvm-project/pull/81599

This fixes a large vertical blank space at the top of the page that was caused by the floating sidebar.

## Before

![image](https://github.com/llvm/llvm-project/assets/279572/5c5ca7ec-455a-4cfa-9712-b92c47eef5b0)

## After

![image](https://github.com/llvm/llvm-project/assets/279572/2d622cb3-1601-4219-b265-2b438e93e163)

>From e57d3a61075c791c36f05f89cafbbdb05e8ee191 Mon Sep 17 00:00:00 2001
From: "J. Ryan Stinnett" <jryans at gmail.com>
Date: Tue, 13 Feb 2024 12:26:06 +0000
Subject: [PATCH] [Docs] Fix large vertical space at top of pages

This fixes a large vertical blank space at the top of the page that was caused
by the floating sidebar.
---
 llvm/docs/_themes/llvm-theme/static/llvm-theme.css | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/llvm/docs/_themes/llvm-theme/static/llvm-theme.css b/llvm/docs/_themes/llvm-theme/static/llvm-theme.css
index 4b04e0cbaccfd3..d8a56a0c262f7b 100644
--- a/llvm/docs/_themes/llvm-theme/static/llvm-theme.css
+++ b/llvm/docs/_themes/llvm-theme/static/llvm-theme.css
@@ -369,3 +369,16 @@ div.viewcode-block:target {
     border-top: 1px solid #ac9;
     border-bottom: 1px solid #ac9;
 }
+
+/*
+Move sidebar to the right without using floats. This fixes a large vertical
+blank space at the top of the page that was caused by the floating sidebar.
+*/
+body {
+    position: relative;
+}
+div.sphinxsidebar {
+    float: none;
+    position: absolute;
+    right: 0;
+}