feat(navbar): match head shows the other gym's brand, centred logo on CrossFit, mobile band

The match head is painted in the other gym's colours with a strip in this site's accent; below 992px it is a slashed band at the bottom of the open menu (menu height from the real header height). The CrossFit page gets the centred logo crossfade, the hero logo has a fixed 52px height, and the hero h1 shadow is softer with the frosted blur at .8.

site/includes/header_video.php

@@ -7,7 +7,7 @@
   <div class="container h-100">
     <div class="d-flex h-100 text-center align-items-center">
       <div class="w-100 text-white">
-        <h1 class="display-3"><img src="<?= base_url('site/assets/img/logos/logo_crossfit_white.svg')?>" alt="CrossFit 3070 — box de CrossFit em Mira" style="opacity: .85; max-width: 320px;" decoding="async"></h1>
+        <h1 class="visually-hidden">CrossFit 3070 — box de CrossFit em Mira</h1>
         <p class="lead mb-0"></p>
       </div>
     </div>

site/includes/navbar.php

@@ -66,8 +66,12 @@ $center_logo = !empty($nav_center_logo);
               if ((int) $g['id'] !== (int) current_gym()['id']) $other_gyms[] = $g;
           }
       }
-      if ($other_gyms): ?>
-      <div class="gym-switch d-flex flex-wrap gap-2 ms-lg-auto py-2 py-lg-0 pe-lg-3">
+      if ($other_gyms):
+          // The match head (style.css) is painted in the first other gym's brand.
+          $head_vars = gym_brand_vars($other_gyms[0]);
+          $head_ink  = str_contains($head_vars, 'on-accent:#FFFFFF') ? ' gym-switch--light-ink' : '';
+      ?>
+      <div class="gym-switch<?= $head_ink ?> d-flex flex-wrap gap-2 ms-lg-auto py-2 py-lg-0 pe-lg-3" style="<?= htmlspecialchars($head_vars) ?>">
         <?php foreach ($other_gyms as $g): ?>
         <?php $g_logo = gym_logo($g); ?>
         <a class="gym-switch-btn<?= $g_logo !== '' ? ' gym-switch-btn--logo' : '' ?>" href="<?= htmlspecialchars(gym_url($g)) ?>" style="<?= htmlspecialchars(gym_brand_vars($g)) ?>">
@@ -102,6 +106,14 @@ $center_logo = !empty($nav_center_logo);
         dock();
     }
 
+    /* ── Mobile menu fills the screen below the bar (style.css --nav-h) ──── */
+    var hdr = document.querySelector('.header-section');
+    if (hdr) {
+        var setNavH = function() { hdr.style.setProperty('--nav-h', hdr.offsetHeight + 'px'); };
+        window.addEventListener('resize', setNavH, { passive: true });
+        setNavH();
+    }
+
     /* ── Eased smooth-scroll helper ──────────────────────────────────────── */
     function smoothScrollTo(targetEl, duration) {
         var start = window.scrollY;