diff --git a/KisaniCal/ISSUES.md b/KisaniCal/ISSUES.md
index 857ab21..76ed4b7 100644
--- a/KisaniCal/ISSUES.md
+++ b/KisaniCal/ISSUES.md
@@ -1938,3 +1938,30 @@ parens checked programmatically; `logHabitDone`/`habitDoneCount` intentionally
 left without `@MainActor` to match the existing nonisolated handler functions
 (`markTaskComplete`, `snoozeTask`) they run alongside in the notification
 delegate callback.
+
+---
+
+## KC-57 — Build error: Color(r:g:b:) used outside its file (coffee brown)
+
+**Status:** Fixed (not build-verified)
+**Reported by:** User (Xcode build errors: "Cannot convert value of type
+'Int' to expected argument type 'Color'", "Extra argument 'b' in call")
+
+### Root cause
+`Color(r:g:b:)` (Double) is declared as `private extension Color` inside
+`DesignTokens.swift` — invisible outside that file by design (only `UIColor`'s
+`init(r:g:b:)` sibling is `private` too, both file-scoped). KC-55/56 used
+`Color(r: 122, g: 84, b: 52)` directly in `SettingsView.swift` and
+`OnboardingView.swift` for the coffee icon's brown background — neither file
+can see the private initializer, so the compiler fell back to unrelated
+overloads and produced the confusing "Cannot convert Int to Color" errors.
+
+### Fix
+Added `AppColors.coffeeBrown` (defined inside `DesignTokens.swift`, where the
+private init IS visible) alongside the other fixed accent colors
+(accent/green/blue/yellow/red). Both call sites now reference
+`AppColors.coffeeBrown` instead of constructing the color inline — matches
+how every other color in the app is centralized, and is accessible from any
+file.
+
+Files: `DesignTokens.swift`, `SettingsView.swift`, `OnboardingView.swift`.
diff --git a/KisaniCal/Theme/DesignTokens.swift b/KisaniCal/Theme/DesignTokens.swift
index 613a94f..88743fa 100644
--- a/KisaniCal/Theme/DesignTokens.swift
+++ b/KisaniCal/Theme/DesignTokens.swift
@@ -9,6 +9,7 @@ struct AppColors {
     static let blue    = Color(r: 77,  g: 157, b: 224)
     static let yellow  = Color(r: 232, g: 184, b: 42)
     static let red     = Color(r: 232, g: 66,  b: 66)
+    static let coffeeBrown = Color(r: 122, g: 84, b: 52)
 
     static let accentSoft  = Color(UIColor { $0.userInterfaceStyle == .dark
         ? UIColor(r: 52, g: 28, b: 14)     // dark: deep warm orange
diff --git a/KisaniCal/Views/OnboardingView.swift b/KisaniCal/Views/OnboardingView.swift
index cd91585..762b05f 100644
--- a/KisaniCal/Views/OnboardingView.swift
+++ b/KisaniCal/Views/OnboardingView.swift
@@ -531,7 +531,7 @@ struct OnboardingView: View {
                             isOn: $bedReminderEnabled)
                         Divider().background(AppColors.border(cs)).padding(.leading, 53)
                         OnboardingHabitToggle(
-                            icon: "cup.and.saucer.fill", iconColor: .white, iconBg: Color(r: 122, g: 84, b: 52),
+                            icon: "cup.and.saucer.fill", iconColor: .white, iconBg: AppColors.coffeeBrown,
                             title: "Coffee reminders",
                             subtitle: "Track when you usually reach for a cup",
                             isOn: $coffeeReminderEnabled)
diff --git a/KisaniCal/Views/SettingsView.swift b/KisaniCal/Views/SettingsView.swift
index c87581e..8fa63cd 100644
--- a/KisaniCal/Views/SettingsView.swift
+++ b/KisaniCal/Views/SettingsView.swift
@@ -1000,7 +1000,7 @@ private struct HabitRemindersSheet: View {
                             HStack(spacing: 11) {
                                 Image(systemName: "cup.and.saucer.fill")
                                     .font(.system(size: 13)).foregroundColor(.white)
-                                    .frame(width: 28, height: 28).background(Color(r: 122, g: 84, b: 52)).cornerRadius(8)
+                                    .frame(width: 28, height: 28).background(AppColors.coffeeBrown).cornerRadius(8)
                                 VStack(alignment: .leading, spacing: 1) {
                                     HStack(spacing: 6) {
                                         Text("Coffee reminders").font(AppFonts.sans(13)).foregroundColor(AppColors.text(cs))