fix(Details): border gecentreerd op icoon via calc

margin-inline-start: calc(icon-size / 2 - border-width / 2)
Border-midden valt samen met icoon-midden, ongeacht fluid icon-size
of toekomstige border-width tokenwijzigingen.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: Jeffrey Lauwers

packages/components-html/src/details/details.css

@@ -115,7 +115,8 @@
    =========================== */
 .dsn-details__content {
   margin-inline-start: calc(
-    var(--dsn-details-icon-size) + var(--dsn-details-summary-gap)
+    var(--dsn-details-icon-size) / 2 -
+      var(--dsn-details-content-border-inline-start-width) / 2
   );
   background-color: var(--dsn-details-content-background-color);
   border-inline-start: var(--dsn-details-content-border-inline-start-width)