style(site): button hover as one continuous extruded wall, no ghost copy

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

site/assets/css/style.css

@@ -377,14 +377,16 @@ section[id] {
   .gym-switch-btn:hover,
   .gym-switch-btn:focus-visible {
     transform: translate(calc(var(--depth) * -1), calc(var(--depth) * -1));
+    /* Face: lit outline + inner glow. Sides: one continuous wall that darkens
+       toward the "wall" it grew from (no alternating stripes, so it reads as a
+       solid extrusion and not as a second copy of the button). */
     box-shadow:
-      inset 0 0 0 2px var(--neon),                           /* lit tube round the face */
-      inset 0 0 14px 1px rgba(var(--fitme-accent-rgb), .55),
-      1px 1px 0 var(--neon-edge),
-      2px 2px 0 var(--neon),
-      3px 3px 0 var(--neon-edge),
-      3px 3px 10px 1px rgba(var(--fitme-accent-rgb), .6),
-      5px 5px 20px 2px rgba(var(--fitme-accent-rgb), .35);
+      inset 0 0 0 2px var(--neon),
+      inset 0 0 14px 1px rgba(var(--fitme-accent-rgb), .45),
+      1px 1px 0 color-mix(in srgb, var(--fitme-accent) 80%, #000),
+      2px 2px 0 color-mix(in srgb, var(--fitme-accent) 62%, #000),
+      3px 3px 0 color-mix(in srgb, var(--fitme-accent) 45%, #000),
+      0 0 16px 2px rgba(var(--fitme-accent-rgb), .4);
   }
 
   .site-btn:active,