fix: center site name in mobile header outside collapsible menu

Agent-Logs-Url: https://github.com/dsaub/proyecto-final/sessions/4d080a78-4752-427f-8205-876ef7b85f7a

Co-authored-by: dsaub <54474838+dsaub@users.noreply.github.com>

tienda/static/css/custom.css

@@ -51,12 +51,23 @@ p.price {
   background-color: #513CB0 !important;
   color: #FFF;
 }
+.navbar.header .container-fluid {
+  position: relative;
+}
 .navbar.header .navbar-brand img {
   border-radius: 10px;
 }
 .navbar.header .navbar-brand {
   color: #FFF !important;
 }
+.navbar.header .site-title-mobile {
+  color: #FFF;
+  position: absolute;
+  left: 50%;
+  transform: translateX(-50%);
+  margin: 0;
+  pointer-events: none;
+}
 .navbar.header .navbar-toggler {
   border-color: #FFF !important;
 }
@@ -276,4 +287,4 @@ p.price {
 
 .texto-ajustado {
   overflow-wrap: anywhere;
-}
+}