Fix print styles for navbar, dark mode, cards and tables; document printing (#2897)

core/scss/layout/_dark.scss

@@ -48,4 +48,15 @@
   // The global `@extend [data-bs-theme='dark']` for light-scoped subtrees
   // inside a dark body lives in `_extends.scss` — with the module system it
   // must have every dark-styling module upstream.
+
+  // Printing a dark page wastes ink/toner and can leave near-white text on
+  // paper, since browsers skip background colors in print by default. Force
+  // every light-dark() token back to its light value regardless of theme.
+  @include media-print() {
+    :root,
+    [data-bs-theme='dark'],
+    [data-theme='dark'] {
+      color-scheme: light !important;
+    }
+  }
 }

core/scss/layout/_navbar.scss

@@ -97,6 +97,10 @@ Navbar
   background: var(--navbar-bg);
   box-shadow: inset 0 calc(-1 * var(--navbar-border-width)) 0 0 var(--navbar-border-color);
 
+  @include media-print() {
+    display: none;
+  }
+
   .navbar-collapse & {
     flex-grow: 1;
   }
@@ -391,6 +395,13 @@ Navbar vertical
       }
     }
   }
+
+  @include media-print() {
+    .navbar-vertical ~ .page {
+      padding-inline-start: 0;
+      padding-inline-end: 0;
+    }
+  }
 }
 
 .navbar-overlap {

core/scss/ui/_cards.scss

@@ -24,6 +24,7 @@
   @include media-print() {
     border: none;
     box-shadow: none;
+    break-inside: avoid;
   }
 
   @at-root a#{&} {

core/scss/ui/_tables.scss

@@ -3,6 +3,16 @@
 .table {
   font: inherit;
 
+  @include media-print() {
+    thead {
+      display: table-header-group;
+    }
+
+    tr {
+      break-inside: avoid;
+    }
+  }
+
   thead {
     th {
       padding-top: $table-th-padding-y;