fix(a11y): improve contrast of version label in sidebar

The "Nextcloud" and version text in the bottom-left sidebar panel
used #0082c9 on a #272525 background, giving a contrast ratio of
~3.7:1. WCAG AA requires 4.5:1 for normal-weight text.

Switching to white (#fff) brings the ratio to ~15:1.

Fixes #9676

Signed-off-by: John Molakvoæ (skjnldsv) <skjnldsv@protonmail.com>

Author: skjnldsv

_shared_assets/static/custom.css

@@ -53,7 +53,9 @@ h6 {
 .rst-versions .rst-current-version {
 	display: flex;
 	align-items: center;
-	color: #0082c9;
+	/* Use white instead of #0082c9 — the NC blue at 3.7:1 on the dark
+	   #272525 sidebar background fails WCAG AA (4.5:1 required). */
+	color: #fff;
 }
 .rst-versions .rst-current-version .fa-caret-down {
 	margin-left: 5px;