minor #1821 [Site] Fix input range color (smnandre)

This PR was merged into the 2.x branch.

Discussion
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[Site] Fix input range color

Previous value made it impossible to use without a background (ex: charts JS demo)

Commits
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51db5b7 [Site] Fix input range color

Author: kbond

ux.symfony.com/assets/styles/_variables.scss

@@ -19,5 +19,5 @@ $size-unit: calc(8px + 1.5625vw);
 
 $font-family-monospace: var(--font-family-code);
 
-$form-range-track-bg: var(--bs-body-bg);
+$form-range-track-bg: #111315ab;
 $form-range-thumb-bg: var(--bs-secondary-color);