Lay the slider controls over the picture like the Kant-IT hero in 1.11.4

Round white arrows left and right, dots bottom right with the active one as
an accent bar, a small pause button and no counter - the design of the hero
slider on kant-it.de. Slider and controls share a positioned shell; arrows
hide on phones. New style property for the active dot colour.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/Content/StyleSchema.php

@@ -207,6 +207,7 @@ final class StyleSchema
             // The slider controls are built by the script next to the slider, so their colours
             // travel as custom properties onto the slider and its controls (target "controls").
             'sliderDotColor' => ['group' => 'slider', 'type' => 'color', 'css' => '--slider-dot', 'label' => 'Punkte', 'target' => 'controls'],
+            'sliderDotActiveColor' => ['group' => 'slider', 'type' => 'color', 'css' => '--slider-dot-active', 'label' => 'Aktiver Punkt', 'target' => 'controls'],
             'sliderControlColor' => ['group' => 'slider', 'type' => 'color', 'css' => '--slider-ink', 'label' => 'Pfeile und Zähler', 'target' => 'controls'],
             'sliderControlBackground' => ['group' => 'slider', 'type' => 'color', 'css' => '--slider-bg', 'label' => 'Hintergrund der Knöpfe', 'target' => 'controls'],
         ];