Define the last three custom properties the css read but nothing set (#2929)

.build/css-vars-baseline.txt

@@ -58,12 +58,3 @@
 --tblr-font-weight-black
 --tblr-gray-dark-lt
 --tblr-gray-lt
-
-# `body { text-align }` - bootstrap leaves the token unset by default, so the
-# declaration never applies.
---tblr-body-text-align
-
-# `.nav-link` font size and the active nav link color (#2287): both drop, so a
-# nav link takes the body font size and keeps the inherited color when active.
---tblr-nav-link-active-color
---tblr-nav-link-font-size

.changeset/fix-last-dangling-tokens.md

@@ -0,0 +1,5 @@
+---
+"@tabler/core": patch
+---
+
+Defined `--tblr-body-text-align`, `--tblr-nav-link-font-size` and `--tblr-nav-link-active-color`, which the css already read.

core/scss/_variables.scss

@@ -363,7 +363,10 @@ $negative-spacers: null !default;
 
 // Body
 
-$body-text-align: null !default;
+// `start`, the property's own initial value, rather than null: `_reboot.scss`
+// reads `--body-text-align` unconditionally, so a null left the declaration
+// invalid.
+$body-text-align: start !default;
 $body-color: $gray-500 !default;
 $body-bg: $white !default;
 
@@ -1519,9 +1522,10 @@ $modal-status-size: $border-width-wide !default;
 // scss-docs-start nav-variables
 $nav-link-padding-y: 0.5rem !default;
 $nav-link-padding-x: 0.75rem !default;
-$nav-link-font-size: null !default;
+$nav-link-font-size: var(--body-font-size) !default;
 $nav-link-font-weight: null !default;
 $nav-link-color: var(--gray-500) !default;
+$nav-link-active-color: var(--body-color) !default;
 $nav-link-hover-color: var(--link-hover-color) !default;
 $nav-link-transition:
   color 0.15s ease-in-out,

core/scss/bootstrap/_root.scss

@@ -75,9 +75,7 @@
   @include rfs($font-size-base, --body-font-size);
   --body-font-weight: #{$font-weight-base};
   --body-line-height: #{$line-height-base};
-  @if $body-text-align != null {
+  --body-text-align: #{$body-text-align};
-    --body-text-align: #{$body-text-align};
-  }
 
   --body-color: light-dark(#{$body-color}, #{$body-color-dark});
   --body-color-rgb: #{to-rgb($body-color)};

core/scss/ui/_nav.scss

@@ -2,6 +2,10 @@
 
 .nav {
   --nav-link-hover-bg: #{color-transparent(var(--nav-link-color), 0.04)};
+  // Read by `.nav-vertical .nav-link.active` below; without it that rule's
+  // color declaration was invalid and the active link fell back to the
+  // inherited color.
+  --nav-link-active-color: #{$nav-link-active-color};
   --nav-vertical-nested-margin-start: #{$nav-vertical-nested-margin-start};
   --nav-vertical-nested-padding-start: #{$nav-vertical-nested-padding-start};
   --nav-link-toggle-padding-x: #{$nav-link-toggle-padding-x};