[clang] [clang][dataflow] Show triangle in `<details>` element. (PR #67431)

[Sam McCall via cfe-commits]

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@@ -122,10 +122,22 @@ code.line:has(.bb-select):before {
   font-size: x-small;
   flex-grow: 1;
 }
-.value summary {
+.value > summary {
   background-color: #ace;
   display: flex;
   justify-content: space-between;
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sam-mccall wrote:

if space-between stays, don't you get a big chunk of space between the arrow and the identity?

https://github.com/llvm/llvm-project/pull/67431