fix(style): Z-Design V5 final - Focus 20% / Unfocus 12%

Ajuste consensuado:
- deriveDarkPalette: 80% black (20% color) focus, 88% black (12% color) unfocus
- derivePanelFrameColors: mismos valores
- Elimina compensación perceptual completamente

Unfocus 12% es más visible que el anterior 4%.

src/core/style.zig

@@ -1120,10 +1120,11 @@ pub fn derivePanelPalette(base: Color, mode: ThemeMode) PanelColorScheme {
 }
 
 /// Derive palette for dark mode (dark backgrounds, light text)
-/// Z-Design V2 + Liquid UI: Mayor contraste para transiciones perceptibles
+/// Z-Design V5: Sincronía Atmosférica (2025-12-31)
-/// - fondo_sin_focus: 4% base color (más oscuro, punto de partida bajo)
+/// - SIN compensación perceptual (causaba más problemas que soluciones)
-/// - fondo_con_focus: 20% base color (brilla al ganar foco, destino alto)
+/// - Blend fijo para TODOS los colores:
-/// Z-Design V3: Perceptual correction boosts low-luminance colors (red/magenta)
+///   - fondo_con_focus: 20% base color / 80% negro
+///   - fondo_sin_focus: 12% base color / 88% negro
 fn deriveDarkPalette(base: Color) PanelColorScheme {
     // Reference colors for dark mode
     const black = Color.soft_black; // RGB(17, 17, 20) - not pure black
@@ -1131,27 +1132,14 @@ fn deriveDarkPalette(base: Color) PanelColorScheme {
     const gray = Color.rgb(128, 128, 128);
     const dark_border = Color.rgb(60, 60, 65);
 
-    // Perceptual correction: only for colors with VERY low luminance (like pure blue ~0.07)
+    // Z-Design V5: Blend fijo sin compensación perceptual
-    // Red (~0.21) is above threshold and won't be affected
+    // Focus: 20% color, Unfocus: 12% color (más visible que el anterior 4%)
-    const base_lum = base.perceptualLuminance();
+    const focus_blend: u8 = 80; // 80% hacia negro = 20% color
-    const threshold: f32 = 0.15; // Only affect colors below this (blue=0.07, red=0.21)
+    const unfocus_blend: u8 = 88; // 88% hacia negro = 12% color
-
-    // Calculate correction factor: if luminance is VERY low, reduce blend %
-    // This makes more of the base color visible, preventing "goes to black" effect
-    const correction: f32 = if (perceptual_correction_enabled and base_lum < threshold)
-        @max(0.75, base_lum / threshold) // Subtle boost for very dark colors
-    else
-        1.0;
-
-    // Apply correction to blend percentages (lower % = more base color visible)
-    const focus_blend: u8 = @intFromFloat(80.0 * correction);
-    const unfocus_blend: u8 = @intFromFloat(96.0 * correction);
 
     return .{
-        // Backgrounds: Liquid UI V2 - mayor recorrido para transición perceptible
+        // Backgrounds: Z-Design V5 - blend fijo
-        // Focus: 20% base, 80% black (destino luminoso) - adjusted by correction
         .fondo_con_focus = base.blendTowards(black, focus_blend),
-        // Sin focus: 4% base, 96% black (punto de partida oscuro) - adjusted
         .fondo_sin_focus = base.blendTowards(black, unfocus_blend),
 
         // Text: high contrast
@@ -1376,22 +1364,20 @@ pub const DerivedPanelColors = struct {
 /// Derive panel frame colors from a single base color.
 ///
 /// Z-Design V5: Sincronía Atmosférica (2025-12-31)
-/// - SIN compensación perceptual (causaba más problemas que soluciones)
+/// - SIN compensación perceptual
-/// - Blend fijo y generoso para TODOS los colores:
+/// - Blend fijo para TODOS los colores:
-///   - Fondo con focus: 18% base / 82% negro
+///   - Fondo con focus: 20% base / 80% negro
-///   - Fondo sin focus: 6% base / 94% negro
+///   - Fondo sin focus: 12% base / 88% negro
 ///
-/// La clave de la fluidez está en pasar bg_transition.current a los widgets,
+/// Los widgets usan bg_transition.current DIRECTAMENTE (mismo fondo que panel)
-/// NO en compensar matemáticamente los colores.
+/// con bisel de 1px para verse como "huecos" o "relieves" integrados.
 pub fn derivePanelFrameColors(base: Color) DerivedPanelColors {
     const black = Color.soft_black;
 
-    // Blend fijo: 18% color con focus, 6% sin focus
+    // Blend fijo: 20% color con focus, 12% sin focus
-    // blendTowards(black, 82) = 18% base + 82% black
-    // blendTowards(black, 94) = 6% base + 94% black
     return .{
-        .focus_bg = base.blendTowards(black, 82),
+        .focus_bg = base.blendTowards(black, 80), // 20% color
-        .unfocus_bg = base.blendTowards(black, 94),
+        .unfocus_bg = base.blendTowards(black, 88), // 12% color
         .border_focus = base,
         .border_unfocus = base.darken(30),
         .title_color = base.lightenHsl(20),
@@ -1399,7 +1385,7 @@ pub fn derivePanelFrameColors(base: Color) DerivedPanelColors {
 }
 
 test "derivePanelFrameColors fixed blend" {
-    // Z-Design V5: All colors use same fixed blend (18% focus, 6% unfocus)
+    // Z-Design V5: All colors use same fixed blend (20% focus, 12% unfocus)
     const blue = Color.rgb(0, 0, 255);
     const derived = derivePanelFrameColors(blue);
 
@@ -1408,10 +1394,10 @@ test "derivePanelFrameColors fixed blend" {
     try std.testing.expectEqual(blue.g, derived.border_focus.g);
     try std.testing.expectEqual(blue.b, derived.border_focus.b);
 
-    // Focus bg: 18% blue + 82% soft_black(17,17,20)
+    // Focus bg: 20% blue + 80% soft_black(17,17,20)
-    // 0.18 * 255 + 0.82 * 20 = 45.9 + 16.4 = 62.3
+    // 0.20 * 255 + 0.80 * 20 = 51 + 16 = 67
-    try std.testing.expect(derived.focus_bg.b > 50);
+    try std.testing.expect(derived.focus_bg.b > 55);
-    try std.testing.expect(derived.focus_bg.b < 80);
+    try std.testing.expect(derived.focus_bg.b < 85);
 }
 
 test "derivePanelFrameColors same blend for all colors" {
@@ -1422,9 +1408,7 @@ test "derivePanelFrameColors same blend for all colors" {
     const blue_derived = derivePanelFrameColors(blue);
     const red_derived = derivePanelFrameColors(red);
 
-    // Both should have ~18% of their primary color channel
+    // Both should have ~20% of their primary color channel
-    // Blue: ~18% of 255 = ~46, Red: ~18% of 255 = ~46
-    // (plus soft_black contribution)
     const blue_intensity = blue_derived.focus_bg.b;
     const red_intensity = red_derived.focus_bg.r;