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>