nav hover: glow instead of the underline bar, and give keyboard focus the same glow

src/components/Nav.astro

@@ -27,7 +27,7 @@ const links = [
           target={l.external ? "_blank" : undefined}
           rel={l.external ? "noopener noreferrer" : undefined}
         >
-          {l.label}<span class="nav__ul" aria-hidden="true"></span>
+          {l.label}
         </a>
       ))}
     </nav>
@@ -98,21 +98,12 @@ const links = [
     color: var(--text);
     text-decoration: none;
   }
-  /* Hover underline - scaleX sprung by the Motion layer, growing from the
-     start of the label. No scroll-spy: it tracked the active section as you
-     scrolled, which read as clunky on a page this short. */
-  .nav__ul {
-    position: absolute;
-    left: 0;
-    right: 0;
-    bottom: -0.45rem;
-    height: 2px;
-    border-radius: 2px;
-    background: linear-gradient(90deg, var(--accent), var(--accent-2));
-    box-shadow: 0 0 8px var(--accent-glow);
-    transform: scaleX(0);
-    transform-origin: 0 50%;
-    pointer-events: none;
+  /* Hover = glow, not an underline (owner call 2026-08-18: the bar read as clunky).
+     Keyboard focus gets the same treatment so the affordance is not mouse-only. */
+  .nav__links a:hover,
+  .nav__links a:focus-visible {
+    color: var(--accent);
+    text-shadow: 0 0 10px var(--accent-glow), 0 0 22px var(--accent-glow);
   }
   .nav__actions {
     display: flex;