V3-16: visual identity (token-level pass)

Direction written before code, per the ticket's own step 1: safety orange stays primary (authentic to the domain, not decorative), a new instrument-blue tertiary is reserved for reference readings (max/average) vs the live figure, ground warmed fractionally, no new font, no motion -- both argued for directly rather than left undecided.

Instrument blue reuses RideMap's existing slow-speed gradient color rather than inventing a new one, so 'same colour, same meaning' holds between the map and stat rows. contrastRatio() implements WCAG 2.x directly and is asserted (11 tests, both themes, AA normal/large) rather than eyeballed. Applied to StatRow's new 'reference' flag on record screen and trip detail's Max/Avg speed rows -- a token-level + targeted pass, not an exhaustive re-skin, named as a deliberate scope reduction alongside the two criteria (outdoor sunlight verification, golden tests) this environment genuinely cannot satisfy.

test/theme_test.dart

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+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:rippr/src/ui/theme.dart';
+
+/// V3-16's acceptance criterion is "contrast ratios meet WCAG AA for body text" --
+/// asserted directly here rather than trusted from a palette chosen by eye. AA is 4.5:1
+/// for normal text, 3:1 for large text (18pt, or 14pt bold and up -- the headline
+/// figures in `BigStat`).
+void main() {
+  group('contrastRatio', () {
+    test('black on white is the maximum possible ratio, 21:1', () {
+      expect(
+        contrastRatio(const Color(0xFF000000), const Color(0xFFFFFFFF)),
+        closeTo(21.0, 0.01),
+      );
+    });
+
+    test('a colour against itself is 1:1', () {
+      const c = Color(0xFFFF5722);
+      expect(contrastRatio(c, c), closeTo(1.0, 0.01));
+    });
+
+    test('is symmetric regardless of argument order', () {
+      const a = Color(0xFF101418);
+      const b = Color(0xFFF2F5F8);
+      expect(contrastRatio(a, b), contrastRatio(b, a));
+    });
+  });
+
+  group('pocketed theme (WCAG AA)', () {
+    final colors = ripprTheme().colorScheme;
+
+    test('body text on the ground meets AA normal text (4.5:1)', () {
+      expect(contrastRatio(colors.onSurface, ripprBackground), greaterThanOrEqualTo(4.5));
+    });
+
+    test('body text on a surface card meets AA normal text (4.5:1)', () {
+      expect(contrastRatio(colors.onSurface, colors.surface), greaterThanOrEqualTo(4.5));
+    });
+
+    test('the primary accent on the ground meets AA large text (3:1)', () {
+      // The accent is used for headline figures and buttons, not small body copy --
+      // held to the large-text threshold, matching how it's actually used on screen.
+      expect(contrastRatio(colors.primary, ripprBackground), greaterThanOrEqualTo(3.0));
+    });
+
+    test('the instrument-blue tertiary on the ground meets AA large text (3:1)', () {
+      expect(contrastRatio(colors.tertiary, ripprBackground), greaterThanOrEqualTo(3.0));
+    });
+
+    test('the instrument-blue tertiary on a surface card meets AA large text (3:1)', () {
+      expect(contrastRatio(colors.tertiary, colors.surface), greaterThanOrEqualTo(3.0));
+    });
+  });
+
+  group('mounted theme (WCAG AA)', () {
+    final colors = ripprMountedTheme().colorScheme;
+
+    test('body text on the ground meets AA normal text (4.5:1)', () {
+      expect(
+        contrastRatio(colors.onSurface, ripprMountedBackground),
+        greaterThanOrEqualTo(4.5),
+      );
+    });
+
+    test('the primary accent on the ground meets AA large text (3:1) -- this is the '
+        'theme sunlight legibility actually depends on', () {
+      expect(
+        contrastRatio(colors.primary, ripprMountedBackground),
+        greaterThanOrEqualTo(3.0),
+      );
+    });
+
+    test('the instrument-blue tertiary meets AA normal text on the ground '
+        '(darkened further than the pocketed theme specifically for this)', () {
+      expect(
+        contrastRatio(colors.tertiary, ripprMountedBackground),
+        greaterThanOrEqualTo(4.5),
+      );
+    });
+  });
+}