XL landscape polish: btn-primary sizing, tray from right, footer bg, layout fixes

- .btn-xl removed; .btn-primary absorbs 4rem sizing (same as PICK SIGS/PICK ROLES)
- Landscape navbar .btn-primary: 3rem → 4rem to match base; XL stays 4rem (consistent)
- _button-pad.scss XL: base .btn ×1.2 (2.4rem); .btn-xl block deleted
- _tray.scss XL (≥1800px): portrait-style tray (slides from right, z-95)
- tray.js: _isLandscape() returns false at ≥1800px; portrait code paths run throughout
- Footer sidebar: background-color added so opaque footer masks tray sliding behind it
- Copyright .footer-container: bottom → top in landscape sidebar
- #id_room_menu: right: 2.5rem override in _room.scss XL block (cascade fix)
- navbar-text XL: 0.65rem × 1.2 = 0.78rem
- All landscape media queries: max-width: 1440px cutoff removed (already done prior)
- btn-xl class stripped from all 5 templates; test_navbar.py assertion updated

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/static_src/scss/_base.scss

@@ -194,7 +194,7 @@ body {
 }
 
 @media (orientation: landscape) {
-    $sidebar-w: 4rem;
+    $sidebar-w: 5rem;
 
     // ── Sidebar layout: navbar ← left, footer → right ────────────────────────────
     body {
@@ -266,11 +266,10 @@ body {
         }
 
         .btn-primary {
-            width: 3rem;
-            height: 3rem;
-            font-size: 0.75rem;
-            border-width: 0.125rem;
-            // margin-left: 0.75rem;
+            width: 4rem;
+            height: 4rem;
+            font-size: 0.875rem;
+            border-width: 0.21rem;
         }
 
         // Login form: offset from fixed sidebars in landscape
@@ -328,6 +327,7 @@ body {
         align-items: center;
         border-top: none;
         border-left: 0.1rem solid rgba(var(--secUser), 0.3);
+        background-color: rgba(var(--priUser), 1);  // opaque: masks tray sliding behind it
         padding: 1rem 0;
         gap: 0;
         z-index: 100;
@@ -348,11 +348,11 @@ body {
 
         .footer-container {
             position: absolute;
-            bottom: 0.75rem;
+            top: 0.75rem;
             text-align: center;
-            font-size: 0.55rem;
+            font-size: 1rem;
             line-height: 1.4;
-            color: rgba(var(--secUser), 0.5);
+            color: rgba(var(--secUser), 1);
 
             br { display: block; }
         }
@@ -372,13 +372,8 @@ body {
         }
 
         .navbar-brand h1  { font-size: 2.4rem; }
-        .navbar-text      { font-size: 1.3rem; }
-
-        .btn-primary {
-            width: 5rem;
-            height: 5rem;
-            font-size: 1.125rem;
-        }
+        .navbar-text      { font-size: 0.78rem; }  // 0.65rem × 1.2
+        .btn-primary      { width: 4rem; height: 4rem; font-size: 0.875rem; }
 
         .input-group {
             left:  $sidebar-xl;
@@ -393,8 +388,8 @@ body {
 
     // h2 page title: portrait-style — centred and full-size on a wide canvas
     body .container .row .col-lg-6 h2 {
-        font-size: 2rem;
-        letter-spacing: 0.33em;
+        font-size: 4rem;
+        letter-spacing: 1em;
         text-align: center;
         text-align-last: center;
     }
@@ -403,7 +398,7 @@ body {
         width: $sidebar-xl;
 
         #id_footer_nav {
-            gap: 4rem;
+            gap: 8rem;
             a { font-size: 3rem; }
         }
 
@@ -419,13 +414,6 @@ body {
             .navbar-brand h1 {
                 font-size: 1.2rem;
             }
-    
-            .btn-primary {
-                width: 3rem;
-                height: 3rem;
-                font-size: 0.75rem;
-                border-width: 0.125rem;
-            }
         }
 
         .row .col-lg-6 h2 {
@@ -492,8 +480,8 @@ body {
         br { display: none; }
 
         small {
-            font-size: 0.7rem;
-            opacity: 0.6;
+            font-size: 0.75rem;
+            opacity: 1;
         }
     }
 }