diff --git a/app/game-frontend/e2e/inGameInfo.spec.ts b/app/game-frontend/e2e/inGameInfo.spec.ts
index 958fefbe..4715b3d6 100644
--- a/app/game-frontend/e2e/inGameInfo.spec.ts
+++ b/app/game-frontend/e2e/inGameInfo.spec.ts
@@ -303,7 +303,7 @@ const install = async (
                         {
                             id: 2,
                             name: '적국',
-                            color: '#800000',
+                            color: '#FFFF00',
                             capitalCityId: 2,
                             level: 1,
                             power: 1000,
@@ -594,6 +594,14 @@ test('global-info renders the ref nation summary columns beside the map', async
     await expect(summary.locator('thead')).toContainText('속령');
     await expect(summary.locator('tbody tr').first()).toHaveText(/아국\s*1,234\s*2\s*1/u);
     await expect(summary.locator('tbody tr').first().locator('td').last()).toHaveAttribute('title', '업');
+    await expect(summary.locator('tbody tr').first().locator('td').first().locator('span')).toHaveCSS(
+        'color',
+        'rgb(255, 255, 255)'
+    );
+    await expect(summary.locator('tbody tr').nth(1).locator('td').first().locator('span')).toHaveCSS(
+        'color',
+        'rgb(0, 0, 0)'
+    );
 
     const geometry = await summary.evaluate((element) => {
         const rect = element.getBoundingClientRect();
diff --git a/app/game-frontend/e2e/joinLayout.spec.ts b/app/game-frontend/e2e/joinLayout.spec.ts
index 0df9167b..e7d8615c 100644
--- a/app/game-frontend/e2e/joinLayout.spec.ts
+++ b/app/game-frontend/e2e/joinLayout.spec.ts
@@ -56,7 +56,7 @@ const installFixture = async (page: Page, state: FixtureState): Promise<void> =>
                     ],
                     warSpecials: [{ key: 'che_무쌍', name: '무쌍', info: '전투 특기' }],
                     nations: [
-                        { id: 1, name: '촉', color: '#66aa44', scoutMessage: '함께 천하를 도모합시다.' },
+                        { id: 1, name: '촉', color: '#FFFF00', scoutMessage: '함께 천하를 도모합시다.' },
                         { id: 2, name: '위', color: '#5577bb', scoutMessage: '능력 있는 장수를 기다립니다.' },
                     ],
                     serverInfo: {
@@ -164,6 +164,12 @@ test('prioritizes core general fields and keeps context and inheritance progress
     await page.setViewportSize({ width: 1200, height: 900 });
     await page.goto('join');
 
+    const nationHeadings = page.locator('.nation-card .nation-name');
+    await expect(nationHeadings.nth(0)).toHaveCSS('background-color', 'rgb(255, 255, 0)');
+    await expect(nationHeadings.nth(0)).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await expect(nationHeadings.nth(1)).toHaveCSS('background-color', 'rgb(85, 119, 187)');
+    await expect(nationHeadings.nth(1)).toHaveCSS('color', 'rgb(255, 255, 255)');
+
     const flow = page.locator('.join-flow');
     const basicPanel = flow.locator('.panel-card').first();
     const advanced = flow.locator('.advanced-options');
@@ -347,6 +353,10 @@ test('keeps the primary creation flow readable without horizontal overflow on mo
     await page.setViewportSize({ width: 390, height: 844 });
     await page.goto('join');
 
+    const nationHeadings = page.locator('.nation-card .nation-name');
+    await expect(nationHeadings.nth(0)).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await expect(nationHeadings.nth(1)).toHaveCSS('color', 'rgb(255, 255, 255)');
+
     await expect(page.getByRole('heading', { name: '장수 기본 정보' })).toBeVisible();
     const mobileGeometry = await page.evaluate(() => {
         const flow = document.querySelector<HTMLElement>('.join-flow');
diff --git a/app/game-frontend/e2e/legacyArchiveViews.spec.ts b/app/game-frontend/e2e/legacyArchiveViews.spec.ts
index 3fbac055..e2091f66 100644
--- a/app/game-frontend/e2e/legacyArchiveViews.spec.ts
+++ b/app/game-frontend/e2e/legacyArchiveViews.spec.ts
@@ -18,7 +18,7 @@ const installArchiveViews = async (page: Page) => {
         const legacy = isLegacyRequest(route);
         const results = operationNames(route).map((operation) => {
             if (operation === 'auth.status') return response({ ok: true });
-            if (operation === 'lobby.info') return response({ myGeneral: null });
+            if (operation === 'lobby.info') return response({ myGeneral: { id: 1, name: '기록장수' } });
             if (operation === 'ranking.getHallOfFameOptions') {
                 return response([
                     {
@@ -128,6 +128,58 @@ const installArchiveViews = async (page: Page) => {
                     nations: [],
                 });
             }
+            if (operation === 'yearbook.getRange') {
+                return response({ firstYearMonth: 22001, lastYearMonth: 22001, currentYearMonth: 22001 });
+            }
+            if (operation === 'public.getMapLayout') {
+                return response({ mapName: 'che', cityList: [], regionMap: {}, levelMap: {} });
+            }
+            if (operation === 'yearbook.getHistory') {
+                return response({
+                    notModified: false,
+                    hash: 'nation-color-contrast',
+                    data: {
+                        year: 220,
+                        month: 1,
+                        map: {
+                            result: true,
+                            version: 0,
+                            startYear: 180,
+                            year: 220,
+                            month: 1,
+                            techLevelLimit: { maxLevel: 12, initialLevel: 1, increaseYears: 5 },
+                            cityList: [],
+                            nationList: [],
+                            spyList: {},
+                            shownByGeneralList: [],
+                            myCity: null,
+                            myNation: null,
+                        },
+                        nations: [
+                            {
+                                id: 1,
+                                name: '암국',
+                                color: '#008000',
+                                level: 1,
+                                power: 100,
+                                generalCount: 1,
+                                cities: ['업'],
+                            },
+                            {
+                                id: 2,
+                                name: '명국',
+                                color: '#FFFF00',
+                                level: 1,
+                                power: 90,
+                                generalCount: 1,
+                                cities: ['허창'],
+                            },
+                        ],
+                        globalHistory: [],
+                        globalAction: [],
+                    },
+                });
+            }
             return { error: { message: `unhandled ${operation}`, data: { code: 'BAD_REQUEST' } } };
         });
         await route.fulfill({ status: 200, contentType: 'application/json', body: JSON.stringify(results) });
@@ -160,3 +212,20 @@ test('왕조 일람과 상세는 이전 서버 source와 profile을 유지한다
     await expect(page.getByText(/이전 1기.*HWE 이전 서버/)).toBeVisible();
     await expect(page.locator('.dynasty-page')).toHaveCSS('width', '1000px');
 });
+
+test('연감 국가 라벨은 밝은 배경에 검정, 어두운 배경에 흰 글자를 사용한다', async ({ page }, testInfo) => {
+    await installArchiveViews(page);
+    await page.setViewportSize({ width: 1200, height: 800 });
+    await page.goto('yearbook');
+
+    const labels = page.locator('.nation-position tbody td:first-child span');
+    await expect(labels).toHaveCount(2);
+    await expect(labels.filter({ hasText: '암국' })).toHaveCSS('color', 'rgb(255, 255, 255)');
+    await expect(labels.filter({ hasText: '명국' })).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await page.screenshot({ path: testInfo.outputPath('yearbook-nation-contrast-desktop.png'), fullPage: true });
+
+    await page.setViewportSize({ width: 500, height: 800 });
+    await expect(labels.filter({ hasText: '암국' })).toHaveCSS('color', 'rgb(255, 255, 255)');
+    await expect(labels.filter({ hasText: '명국' })).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await page.screenshot({ path: testInfo.outputPath('yearbook-nation-contrast-mobile.png'), fullPage: true });
+});
diff --git a/app/game-frontend/e2e/mainNavigation.spec.ts b/app/game-frontend/e2e/mainNavigation.spec.ts
index b3dc3348..4e53a936 100644
--- a/app/game-frontend/e2e/mainNavigation.spec.ts
+++ b/app/game-frontend/e2e/mainNavigation.spec.ts
@@ -1455,18 +1455,29 @@ test('main general card uses local turn time and command clock tracks corrected
     await expect(frozenClock).toHaveText('09:08:30');
 });
 
-test('pure NPC message senders are not rendered as reply targets', async ({ page }) => {
-    const target = (generalId: number, generalName: string) => ({
+test('message targets keep reply behavior and use nation-color contrast in labels and select options', async ({
+    page,
+}) => {
+    const target = (generalId: number, generalName: string, color = '#008000', nationId = 1, nationName = '위') => ({
         generalId,
         generalName,
-        nationId: 1,
-        nationName: '위',
-        color: '#008000',
+        nationId,
+        nationName,
+        color,
         icon: '',
     });
     const messages = {
         ...emptyMessages(0),
         public: [
+            {
+                id: 103,
+                text: '밝은 국가 메시지',
+                time: '2026-08-12 12:01:00',
+                msgType: 'public',
+                src: target(23, '밝은장수', '#FFFF00', 2, '밝은국'),
+                dest: null,
+                option: {},
+            },
             {
                 id: 102,
                 text: 'NPC 메시지',
@@ -1505,6 +1516,13 @@ test('pure NPC message senders are not rendered as reply targets', async ({ page
                     color: '#008000',
                     general: [[21, '유저장수', 0]],
                 },
+                {
+                    nationId: 2,
+                    mailbox: 9002,
+                    name: '밝은국',
+                    color: '#FFFF00',
+                    general: [[23, '밝은장수', 0]],
+                },
             ],
         },
     };
@@ -1514,13 +1532,39 @@ test('pure NPC message senders are not rendered as reply targets', async ({ page
 
     const npcMessage = page.locator('.desktop-message-panel .msg-plate[data-id="102"]');
     const userMessage = page.locator('.desktop-message-panel .msg-plate[data-id="101"]');
+    const brightMessage = page.locator('.desktop-message-panel .msg-plate[data-id="103"]');
     await expect(npcMessage.locator('.msg-header')).toContainText('순수NPC:위');
     await expect(npcMessage.locator('.msg-header')).not.toContainText('↩');
     await expect(npcMessage.getByRole('button', { name: /순수NPC/ })).toHaveCount(0);
     await expect(userMessage.getByRole('button', { name: /유저장수:위.*↩/ })).toBeVisible();
+    await expect(userMessage.locator('.msg-target')).toHaveCSS('color', 'rgb(255, 255, 255)');
+    const brightTarget = brightMessage.locator('.msg-target');
+    await expect(brightTarget).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await brightTarget.hover();
+    await expect(brightTarget).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await brightTarget.focus();
+    await expect(brightTarget).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await brightTarget.hover();
+    await page.mouse.down();
+    await expect(brightTarget).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await page.mouse.up();
+    const mailbox = page.locator('.desktop-message-panel #mailbox_list');
+    await expect(mailbox.locator('optgroup[label="위"]')).toHaveCSS('color', 'rgb(255, 255, 255)');
+    await expect(mailbox.locator('optgroup[label="밝은국"]')).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await expect(mailbox.locator('option[value="23"]')).toHaveCSS('color', 'rgb(0, 0, 0)');
     await userMessage.getByRole('button', { name: /유저장수:위.*↩/ }).click();
-    await expect(page.locator('.desktop-message-panel #mailbox_list')).toHaveValue('21');
+    await expect(mailbox).toHaveValue('21');
     await persistArtifact(page, `${basePath.slice(1)}-npc-reply-targets-desktop-1200`);
+
+    await page.setViewportSize({ width: 500, height: 900 });
+    const mobilePanel = page.locator('.mobile-message-panel');
+    await expect(mobilePanel.locator('.msg-plate[data-id="101"] .msg-target')).toHaveCSS(
+        'color',
+        'rgb(255, 255, 255)'
+    );
+    await expect(mobilePanel.locator('.msg-plate[data-id="103"] .msg-target')).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await expect(mobilePanel.locator('#mailbox_list optgroup[label="밝은국"]')).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await persistArtifact(page, `${basePath.slice(1)}-message-nation-contrast-mobile-500`);
 });
 
 test('main reserved-turn picker renders the Ref category order and raised button depth', async ({ page }) => {
diff --git a/app/game-frontend/e2e/pastPlays.spec.ts b/app/game-frontend/e2e/pastPlays.spec.ts
index aeae5744..5ee95071 100644
--- a/app/game-frontend/e2e/pastPlays.spec.ts
+++ b/app/game-frontend/e2e/pastPlays.spec.ts
@@ -9,7 +9,10 @@ const gameProfileId = gameProfile.split(':', 1)[0] ?? 'che';
 const operationNames = (route: Route) =>
     decodeURIComponent(new URL(route.request().url()).pathname.split('/trpc/')[1] ?? '').split(',');
 
-const installArchive = async (page: Page, options: { battleAvailable?: boolean; abandoned?: boolean } = {}) => {
+const installArchive = async (
+    page: Page,
+    options: { battleAvailable?: boolean; abandoned?: boolean; nationColor?: string } = {}
+) => {
     const archiveRequestBodies: string[] = [];
     await page.addInitScript((profile) => {
         localStorage.setItem('sammo-game-token', 'ga_archive');
@@ -44,7 +47,7 @@ const installArchive = async (page: Page, options: { battleAvailable?: boolean;
                                     lastYearMonth: 21403,
                                     nationId: 2,
                                     nationName: '촉',
-                                    nationColor: '#800000',
+                                    nationColor: options.nationColor ?? '#800000',
                                     leadership: 91,
                                     strength: 98,
                                     intel: 77,
@@ -69,7 +72,7 @@ const installArchive = async (page: Page, options: { battleAvailable?: boolean;
                     serverId: 'che_2024_01',
                     generalNo: 17,
                     dynastyPath: '/dynasty/7?source=legacy',
-                    nation: { name: '촉', color: '#800000' },
+                    nation: { name: '촉', color: options.nationColor ?? '#800000' },
                     general: {
                         id: 17,
                         name: '관우',
@@ -175,6 +178,29 @@ test('지난 플레이 관직은 숫자 대신 저장된 Ref 표시명으로 나
     await expect(generalRow).not.toContainText('che_');
 });
 
+test('지난 플레이 국가 라벨은 밝은 국가색과 어두운 국가색에 대비되는 글자색을 쓴다', async ({
+    page,
+}, testInfo) => {
+    await installArchive(page, { nationColor: '#FFFF00' });
+    await page.setViewportSize({ width: 1200, height: 900 });
+    await page.goto('past-plays');
+
+    const nationLabel = page.locator('.season-card .nation-name').first();
+    await expect(nationLabel).toHaveCSS('background-color', 'rgb(255, 255, 0)');
+    await expect(nationLabel).toHaveCSS('color', 'rgb(0, 0, 0)');
+
+    await page.locator('.detail-toggle').click();
+    const generalTitle = page.locator('[data-general-basic-card] .general-title');
+    await expect(generalTitle).toHaveCSS('background-color', 'rgb(255, 255, 0)');
+    await expect(generalTitle).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await page.screenshot({ path: testInfo.outputPath('past-play-nation-contrast-desktop.png'), fullPage: true });
+
+    await page.setViewportSize({ width: 500, height: 900 });
+    await expect(nationLabel).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await expect(generalTitle).toHaveCSS('color', 'rgb(0, 0, 0)');
+    await page.screenshot({ path: testInfo.outputPath('past-play-nation-contrast-mobile.png'), fullPage: true });
+});
+
 test('보존되지 않은 과거 전투 집계는 0으로 꾸미지 않고 가용성 경계를 표시한다', async ({ page }) => {
     await installArchive(page, { battleAvailable: false });
     await page.goto('past-plays');
diff --git a/app/game-frontend/src/components/main/GeneralBasicCard.vue b/app/game-frontend/src/components/main/GeneralBasicCard.vue
index 9956af33..3903bdf8 100644
--- a/app/game-frontend/src/components/main/GeneralBasicCard.vue
+++ b/app/game-frontend/src/components/main/GeneralBasicCard.vue
@@ -7,6 +7,7 @@ import { formatLocalTimeSeconds } from '../../utils/legacyDateTime';
 import { legacyExperiencePercent, ratioPercent } from '../../utils/legacyProgress';
 import { DEFAULT_GENERAL_ICON_URL, resolveGeneralIconBackgroundImage } from '../../utils/generalIcon';
 import { configuredGameAssetUrl } from '../../utils/imageAssets';
+import { legacyLuminanceTextColor } from '../../utils/legacyNationColor';
 
 interface GeneralStats {
     leadership: number;
@@ -155,19 +156,11 @@ const injuryInfo = computed(() => {
     return { text: '건강', color: '#ffffff' };
 });
 
-const isBrightColor = (color: string): boolean => {
-    const normalized = /^#[0-9a-f]{6}$/iu.test(color) ? color.slice(1) : '173d27';
-    const red = Number.parseInt(normalized.slice(0, 2), 16);
-    const green = Number.parseInt(normalized.slice(2, 4), 16);
-    const blue = Number.parseInt(normalized.slice(4, 6), 16);
-    return (red * 299 + green * 587 + blue * 114) / 1000 >= 150;
-};
-
 const titleStyle = computed(() => {
     const backgroundColor = props.nationColor || '#173d27';
     return {
         backgroundColor,
-        color: isBrightColor(backgroundColor) ? '#000000' : '#ffffff',
+        color: legacyLuminanceTextColor(backgroundColor),
     };
 });
 
diff --git a/app/game-frontend/src/components/main/MessagePanel.vue b/app/game-frontend/src/components/main/MessagePanel.vue
index c51f378f..6275f273 100644
--- a/app/game-frontend/src/components/main/MessagePanel.vue
+++ b/app/game-frontend/src/components/main/MessagePanel.vue
@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import { computed, reactive } from 'vue';
 import type { MessageType } from '@sammo-ts/logic';
+import { legacyLuminanceTextColor } from '../../utils/legacyNationColor';
 import SkeletonLines from '../ui/SkeletonLines.vue';
 import MessagePlate from './MessagePlate.vue';
 
@@ -172,14 +173,20 @@ const forwardResponse = (messageId: number, response: boolean) => {
                         v-for="group in mailboxGroups"
                         :key="group.label"
                         :label="group.label"
-                        :style="{ backgroundColor: group.color ?? '#000000', color: '#ffffff' }"
+                        :style="{
+                            backgroundColor: group.color ?? '#000000',
+                            color: legacyLuminanceTextColor(group.color ?? '#000000'),
+                        }"
                     >
                         <option
                             v-for="option in group.options"
                             :key="`${group.label}-${option.value}`"
                             :value="option.value"
                             :disabled="option.disabled"
-                            :style="{ backgroundColor: option.color ?? '#000000', color: '#ffffff' }"
+                            :style="{
+                                backgroundColor: option.color ?? '#000000',
+                                color: legacyLuminanceTextColor(option.color ?? '#000000'),
+                            }"
                         >
                             {{ option.label }}
                         </option>
diff --git a/app/game-frontend/src/components/main/MessagePlate.vue b/app/game-frontend/src/components/main/MessagePlate.vue
index 91dcc835..d102241a 100644
--- a/app/game-frontend/src/components/main/MessagePlate.vue
+++ b/app/game-frontend/src/components/main/MessagePlate.vue
@@ -2,6 +2,7 @@
 import { computed, onBeforeUnmount, onMounted, ref } from 'vue';
 import type { MessageType } from '@sammo-ts/logic';
 import { DEFAULT_GENERAL_ICON_URL, resolveMessageGeneralIconUrl, useDefaultGeneralIcon } from '../../utils/generalIcon';
+import { isLegacyNationColorBright } from '../../utils/legacyNationColor';
 
 interface MessageTarget {
     generalId: number;
@@ -95,25 +96,13 @@ const scheduleDeleteExpiry = () => {
     }, delay);
 };
 
-const isBright = (color: string): boolean => {
-    const match = /^#([0-9a-f]{6})$/i.exec(color);
-    if (!match) {
-        return false;
-    }
-    const value = Number.parseInt(match[1]!, 16);
-    const red = (value >> 16) & 0xff;
-    const green = (value >> 8) & 0xff;
-    const blue = value & 0xff;
-    return red * 0.299 + green * 0.587 + blue * 0.114 > 160;
-};
-
 const iconUrl = computed(() => resolveMessageGeneralIconUrl(props.message.src.icon));
 const canReplyToGeneral = (target: MessageTarget): boolean => props.replyableGeneralIds.includes(target.generalId);
 
 const targetClass = (target: MessageTarget) => ({
     'msg-target': true,
-    'msg-bright': isBright(target.color),
-    'msg-dark': !isBright(target.color),
+    'msg-bright': isLegacyNationColorBright(target.color),
+    'msg-dark': !isLegacyNationColorBright(target.color),
 });
 
 const setTarget = (target: MessageTarget) => {
diff --git a/app/game-frontend/src/components/main/NationBasicCard.vue b/app/game-frontend/src/components/main/NationBasicCard.vue
index 6af4b379..ba738b29 100644
--- a/app/game-frontend/src/components/main/NationBasicCard.vue
+++ b/app/game-frontend/src/components/main/NationBasicCard.vue
@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import SkeletonLines from '../ui/SkeletonLines.vue';
-import { legacyNationTextColor } from '../../utils/legacyNationColor';
+import { legacyLuminanceTextColor } from '../../utils/legacyNationColor';
 import { formatOfficerLevelText } from '../../utils/nationFormat';
 import { getNpcColor } from '../../utils/npcColor';
 
@@ -60,7 +60,7 @@ const displayChiefName = (chief: NationChief | undefined): string => {
         <div v-else class="nation-grid">
             <div
                 class="title"
-                :style="{ backgroundColor: props.nation.color, color: legacyNationTextColor(props.nation.color) }"
+                :style="{ backgroundColor: props.nation.color, color: legacyLuminanceTextColor(props.nation.color) }"
             >
                 {{ props.nation.name }}
             </div>
diff --git a/app/game-frontend/src/utils/legacyNationColor.ts b/app/game-frontend/src/utils/legacyNationColor.ts
index db00faa6..6d32d5fa 100644
--- a/app/game-frontend/src/utils/legacyNationColor.ts
+++ b/app/game-frontend/src/utils/legacyNationColor.ts
@@ -21,3 +21,17 @@ const lightTextBackgrounds = new Set([
 
 export const legacyNationTextColor = (backgroundColor: string): '#FFFFFF' | '#000000' =>
     lightTextBackgrounds.has(backgroundColor.toUpperCase()) ? '#FFFFFF' : '#000000';
+
+/** Mirrors Ref `isBrightColor()`, used by Vue nation labels and message targets. */
+export const isLegacyNationColorBright = (backgroundColor: string): boolean => {
+    const normalized = backgroundColor.trim().replace(/^#/u, '');
+    if (!/^[0-9a-f]{6}$/iu.test(normalized)) return false;
+
+    const red = Number.parseInt(normalized.slice(0, 2), 16);
+    const green = Number.parseInt(normalized.slice(2, 4), 16);
+    const blue = Number.parseInt(normalized.slice(4, 6), 16);
+    return red * 0.299 + green * 0.587 + blue * 0.114 > 140;
+};
+
+export const legacyLuminanceTextColor = (backgroundColor: string): '#000000' | '#FFFFFF' =>
+    isLegacyNationColorBright(backgroundColor) ? '#000000' : '#FFFFFF';
diff --git a/app/game-frontend/src/views/CurrentCityView.vue b/app/game-frontend/src/views/CurrentCityView.vue
index c8e92d0b..f3251a8f 100644
--- a/app/game-frontend/src/views/CurrentCityView.vue
+++ b/app/game-frontend/src/views/CurrentCityView.vue
@@ -4,6 +4,7 @@ import { useRoute, useRouter } from 'vue-router';
 import { cityLevelMap, formatOfficerLevelText, regionMap } from '../utils/nationFormat';
 import { getNpcColor } from '../utils/npcColor';
 import { resolveGeneralIconUrl, useDefaultGeneralIcon } from '../utils/generalIcon';
+import { legacyNationTextColor } from '../utils/legacyNationColor';
 import { trpc } from '../utils/trpc';
 
 type Result = Awaited<ReturnType<typeof trpc.world.getCurrentCity.query>>;
@@ -57,31 +58,11 @@ const populationRate = computed(() => {
     if (!city.value || city.value.population === null) return '?';
     return String(Math.round((city.value.population / city.value.populationMax) * 10_000) / 100);
 });
-const contrastColors = new Set([
-    '',
-    '#330000',
-    '#FF0000',
-    '#800000',
-    '#A0522D',
-    '#FF6347',
-    '#808000',
-    '#008000',
-    '#2E8B57',
-    '#008080',
-    '#6495ED',
-    '#0000FF',
-    '#000080',
-    '#483D8B',
-    '#7B68EE',
-    '#800080',
-    '#A9A9A9',
-    '#000000',
-]);
 const cityTitleStyle = computed(() => {
     const backgroundColor = city.value?.nationColor.toUpperCase() ?? '#000000';
     return {
         backgroundColor,
-        color: contrastColors.has(backgroundColor) ? '#FFFFFF' : '#000000',
+        color: legacyNationTextColor(backgroundColor),
     };
 });
 const woundedStat = (value: number, injury: number) =>
diff --git a/app/game-frontend/src/views/DiplomacyView.vue b/app/game-frontend/src/views/DiplomacyView.vue
index e6f590d4..1327d28e 100644
--- a/app/game-frontend/src/views/DiplomacyView.vue
+++ b/app/game-frontend/src/views/DiplomacyView.vue
@@ -10,6 +10,7 @@ import { useRouter } from 'vue-router';
 import { trpc } from '../utils/trpc';
 import { resolveGeneralIconUrl } from '../utils/generalIcon';
 import { formatSeoulDateTime } from '../utils/legacyDateTime';
+import { legacyLuminanceTextColor } from '../utils/legacyNationColor';
 
 type DiplomacyResponse = Awaited<ReturnType<typeof trpc.diplomacy.getLetters.query>>;
 type DiplomacyLetter = DiplomacyResponse['letters'][number];
@@ -212,18 +213,9 @@ const stateOptionLabelMap: Record<string, string> = {
 const targetNation = (letter: DiplomacyLetter) =>
     letter.src.nationId === data.value?.myNationId ? letter.dest : letter.src;
 
-const isBrightColor = (color: string): boolean => {
-    const normalized = color.trim().replace(/^#/u, '');
-    if (!/^[0-9a-f]{6}$/iu.test(normalized)) return false;
-    const red = Number.parseInt(normalized.slice(0, 2), 16);
-    const green = Number.parseInt(normalized.slice(2, 4), 16);
-    const blue = Number.parseInt(normalized.slice(4, 6), 16);
-    return red * 0.299 + green * 0.587 + blue * 0.114 > 170;
-};
-
 const nationStyle = (color: string) => ({
     backgroundColor: color || '#315f86',
-    color: isBrightColor(color) ? '#000' : '#fff',
+    color: legacyLuminanceTextColor(color || '#315f86'),
 });
 
 const signerIcon = (signer: DiplomacyLetter['src'] | DiplomacyLetter['dest']): string | null => {
diff --git a/app/game-frontend/src/views/GlobalInfoView.vue b/app/game-frontend/src/views/GlobalInfoView.vue
index b9ac9f48..229856a1 100644
--- a/app/game-frontend/src/views/GlobalInfoView.vue
+++ b/app/game-frontend/src/views/GlobalInfoView.vue
@@ -3,7 +3,7 @@ import { computed, onMounted, ref, watch } from 'vue';
 import { useRouter } from 'vue-router';
 import MapViewer from '../components/main/MapViewer.vue';
 import { trpc } from '../utils/trpc';
-import { legacyNationTextColor } from '../utils/legacyNationColor';
+import { legacyLuminanceTextColor } from '../utils/legacyNationColor';
 
 type Result = Awaited<ReturnType<typeof trpc.world.getGlobalInfo.query>>;
 type Layout = Awaited<ReturnType<typeof trpc.world.getMapLayout.query>>;
@@ -19,7 +19,7 @@ const stateClass = (value: number) => `state-${value}`;
 const nationMap = computed(() => new Map(data.value?.nations.map((nation) => [nation.id, nation]) ?? []));
 const nationNameStyle = (color: string) => ({
     backgroundColor: color,
-    color: legacyNationTextColor(color),
+    color: legacyLuminanceTextColor(color),
 });
 watch(
     matrixElement,
diff --git a/app/game-frontend/src/views/JoinView.vue b/app/game-frontend/src/views/JoinView.vue
index 3f65db42..e3b3b64e 100644
--- a/app/game-frontend/src/views/JoinView.vue
+++ b/app/game-frontend/src/views/JoinView.vue
@@ -12,6 +12,7 @@ import { getNpcColor } from '../utils/npcColor';
 import { formatSeoulDateTime } from '../utils/legacyDateTime';
 import { resolveGeneralIconUrl, useDefaultGeneralIcon } from '../utils/generalIcon';
 import { abilityLeadint, abilityLeadpow, abilityPowint, abilityRand, type GeneralStats } from '../utils/generalStats';
+import { legacyLuminanceTextColor } from '../utils/legacyNationColor';
 
 type JoinConfig = Awaited<ReturnType<typeof trpc.join.getConfig.query>>;
 type JoinInput = Parameters<typeof trpc.join.createGeneral.mutate>[0];
@@ -945,7 +946,15 @@ onUnmounted(() => {
                     <div v-if="nationList.length === 0" class="muted">국가 정보가 아직 준비되지 않았습니다.</div>
                     <div v-else class="nation-list">
                         <article v-for="nation in nationList" :key="nation.id" class="nation-card">
-                            <h3 class="nation-name" :style="{ backgroundColor: nation.color }">{{ nation.name }}</h3>
+                            <h3
+                                class="nation-name"
+                                :style="{
+                                    backgroundColor: nation.color,
+                                    color: legacyLuminanceTextColor(nation.color),
+                                }"
+                            >
+                                {{ nation.name }}
+                            </h3>
                             <p class="nation-message">{{ nation.scoutMessage ?? '권유문 없음' }}</p>
                         </article>
                     </div>
diff --git a/app/game-frontend/src/views/NationListView.vue b/app/game-frontend/src/views/NationListView.vue
index 4b4ee10e..c71eea5c 100644
--- a/app/game-frontend/src/views/NationListView.vue
+++ b/app/game-frontend/src/views/NationListView.vue
@@ -3,6 +3,7 @@ import { onMounted, ref } from 'vue';
 
 import { formatNationLevelText, formatOfficerLevelText } from '../utils/nationFormat';
 import { getNpcColor } from '../utils/npcColor';
+import { legacyNationTextColor } from '../utils/legacyNationColor';
 import { trpc } from '../utils/trpc';
 
 type Directory = Awaited<ReturnType<typeof trpc.world.getNationDirectory.query>>;
@@ -12,27 +13,6 @@ const nations = ref<Directory>([]);
 const loading = ref(false);
 const error = ref('');
 
-const whiteTextColors = new Set([
-    '',
-    '#330000',
-    '#ff0000',
-    '#800000',
-    '#a0522d',
-    '#ff6347',
-    '#808000',
-    '#008000',
-    '#2e8b57',
-    '#008080',
-    '#6495ed',
-    '#0000ff',
-    '#000080',
-    '#483d8b',
-    '#7b68ee',
-    '#800080',
-    '#a9a9a9',
-    '#000000',
-]);
-
 const loadDirectory = async () => {
     loading.value = true;
     error.value = '';
@@ -45,8 +25,6 @@ const loadDirectory = async () => {
     }
 };
 
-const headerTextColor = (color: string): string => (whiteTextColors.has(color.toLowerCase()) ? '#ffffff' : '#000000');
-
 const officerName = (nation: Nation, officerLevel: number) =>
     nation.officers.find((officer) => officer.officerLevel === officerLevel)?.general;
 const displayGeneralName = (general: { name: string; npcState: number }) =>
@@ -92,7 +70,7 @@ onMounted(() => {
                         <td
                             colspan="8"
                             class="center nation-title"
-                            :style="{ color: headerTextColor(nation.color), backgroundColor: nation.color }"
+                            :style="{ color: legacyNationTextColor(nation.color), backgroundColor: nation.color }"
                         >
                             【 {{ nation.name }} 】
                         </td>
diff --git a/app/game-frontend/src/views/PastPlaysView.vue b/app/game-frontend/src/views/PastPlaysView.vue
index 58a36570..3e79efe3 100644
--- a/app/game-frontend/src/views/PastPlaysView.vue
+++ b/app/game-frontend/src/views/PastPlaysView.vue
@@ -14,6 +14,7 @@ import {
 import LegacyGeneralProgress from '../components/ui/LegacyGeneralProgress.vue';
 import PanelCard from '../components/ui/PanelCard.vue';
 import SkeletonLines from '../components/ui/SkeletonLines.vue';
+import { legacyLuminanceTextColor } from '../utils/legacyNationColor';
 import { trpc } from '../utils/trpc';
 
 type Archive = Awaited<ReturnType<typeof trpc.archive.myPastPlays.query>>;
@@ -282,7 +283,10 @@ onMounted(() => {
                             <td>
                                 <span
                                     class="nation-name"
-                                    :style="{ backgroundColor: general.nationColor, color: '#fff' }"
+                                    :style="{
+                                        backgroundColor: general.nationColor,
+                                        color: legacyLuminanceTextColor(general.nationColor),
+                                    }"
                                 >
                                     {{ general.nationName }}
                                 </span>
diff --git a/app/game-frontend/src/views/SelectGeneralView.vue b/app/game-frontend/src/views/SelectGeneralView.vue
index ce654da9..8ce999b2 100644
--- a/app/game-frontend/src/views/SelectGeneralView.vue
+++ b/app/game-frontend/src/views/SelectGeneralView.vue
@@ -6,6 +6,7 @@ import { useGameFeedback } from '../composables/useGameFeedback';
 import { useSessionStore } from '../stores/session';
 import { formatSeoulDateTime } from '../utils/legacyDateTime';
 import { resolveGeneralIconUrl, useDefaultGeneralIcon } from '../utils/generalIcon';
+import { legacyLuminanceTextColor } from '../utils/legacyNationColor';
 import { trpc } from '../utils/trpc';
 
 type JoinConfig = Awaited<ReturnType<typeof trpc.join.getConfig.query>>;
@@ -144,29 +145,6 @@ const personalityName = (key: string | null): string | null => {
 const personalityInfo = (key: string | null): string =>
     key ? (personalities.value.find((entry) => entry.key === key)?.info ?? '') : '';
 
-const lightTextNationColors = new Set([
-    '',
-    '#330000',
-    '#FF0000',
-    '#800000',
-    '#A0522D',
-    '#FF6347',
-    '#808000',
-    '#008000',
-    '#2E8B57',
-    '#008080',
-    '#6495ED',
-    '#0000FF',
-    '#000080',
-    '#483D8B',
-    '#7B68EE',
-    '#800080',
-    '#A9A9A9',
-    '#000000',
-]);
-const nationTextColor = (color: string): string =>
-    lightTextNationColors.has(color.toUpperCase()) ? '#FFFFFF' : '#000000';
-
 const selectCandidate = async (candidate: Candidate): Promise<void> => {
     if (!hasGeneral.value) {
         selectedUniqueName.value = candidate.uniqueName;
@@ -310,7 +288,7 @@ onBeforeUnmount(() => {
                     v-for="nation in nations"
                     :key="nation.id"
                     :style="{
-                        color: nationTextColor(nation.color),
+                        color: legacyLuminanceTextColor(nation.color),
                         backgroundColor: nation.color,
                     }"
                 >
diff --git a/app/game-frontend/src/views/YearbookView.vue b/app/game-frontend/src/views/YearbookView.vue
index 9afbe936..26d799fd 100644
--- a/app/game-frontend/src/views/YearbookView.vue
+++ b/app/game-frontend/src/views/YearbookView.vue
@@ -4,6 +4,7 @@ import { useRoute, useRouter } from 'vue-router';
 
 import MapViewer from '../components/main/MapViewer.vue';
 import { formatLog } from '../utils/formatLog';
+import { legacyLuminanceTextColor } from '../utils/legacyNationColor';
 import { trpc } from '../utils/trpc';
 
 type YearbookRange = Awaited<ReturnType<typeof trpc.yearbook.getRange.query>>;
@@ -201,7 +202,13 @@ onMounted(async () => {
                             :key="nation.id"
                         >
                             <td>
-                                <span :style="{ backgroundColor: nation.color }">{{ nation.name }}</span>
+                                <span
+                                    :style="{
+                                        backgroundColor: nation.color,
+                                        color: legacyLuminanceTextColor(nation.color),
+                                    }"
+                                    >{{ nation.name }}</span
+                                >
                             </td>
                             <td>{{ nation.power.toLocaleString() }}</td>
                             <td>{{ nation.generalCount.toLocaleString() }}</td>
diff --git a/app/game-frontend/test/legacyNationColor.test.ts b/app/game-frontend/test/legacyNationColor.test.ts
new file mode 100644
index 00000000..6ff88e74
--- /dev/null
+++ b/app/game-frontend/test/legacyNationColor.test.ts
@@ -0,0 +1,29 @@
+import assert from 'node:assert/strict';
+import { describe, it } from 'node:test';
+
+import {
+    isLegacyNationColorBright,
+    legacyLuminanceTextColor,
+    legacyNationTextColor,
+} from '../src/utils/legacyNationColor.ts';
+
+void describe('legacy nation color contrast', () => {
+    void it('matches Ref isBrightColor luminance and its strict threshold', () => {
+        assert.equal(isLegacyNationColorBright('#FFFF00'), true);
+        assert.equal(isLegacyNationColorBright('#008000'), false);
+        assert.equal(isLegacyNationColorBright('#20B2AA'), false);
+        assert.equal(isLegacyNationColorBright('#6495ED'), true);
+        assert.equal(isLegacyNationColorBright('not-a-color'), false);
+    });
+
+    void it('uses black text on bright backgrounds and white text on dark backgrounds', () => {
+        assert.equal(legacyLuminanceTextColor('#FFFF00'), '#000000');
+        assert.equal(legacyLuminanceTextColor('#008000'), '#FFFFFF');
+        assert.equal(legacyLuminanceTextColor('#A9A9A9'), '#000000');
+    });
+
+    void it('keeps the separate Ref PHP newColor palette contract', () => {
+        assert.equal(legacyNationTextColor('#A9A9A9'), '#FFFFFF');
+        assert.equal(legacyNationTextColor('#FFFF00'), '#000000');
+    });
+});