feat(login): configurable logo size + hideable heading/subtitle

Login header customization for white-label deployments, all defaults
preserve current behaviour:

- LOGIN_LOGO_MAX_HEIGHT / LOGIN_LOGO_MAX_WIDTH (any CSS length): the logo
  box is otherwise a fixed 64x64 (w-16/h-16), which fits a wide wordmark to
  ~13px tall. When either is set, the fixed box is dropped and the logo
  renders at the configured size.
- LOGIN_SHOW_HEADING / LOGIN_SHOW_SUBTITLE (default true): hide the
  {appName} heading and/or the subtitle when the logo already reads as the
  brand (e.g. a wordmark) and they'd be redundant.

Applied to the standard login header; wired through the existing config
registry (CONFIG_ENV_MAP) -> /api/config -> useConfig.

Refs #519.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

app/(main)/[locale]/login/page.tsx

@@ -133,9 +133,16 @@ export default function LoginPage() {
   const isMobileHandoff = Boolean(mobileRedirectUri);
   const { login, loginDemo, isLoading, error, clearError, isAuthenticated } = useAuthStore();
   const { theme, setTheme, initializeTheme } = useThemeStore(useShallow((s) => ({ theme: s.theme, setTheme: s.setTheme, initializeTheme: s.initializeTheme })));
-  const { appName, jmapServerUrl: configuredServerUrl, oauthEnabled, oauthOnly, oauthClientId: globalOauthClientId, oauthIssuerUrl: globalOauthIssuerUrl, oauthScopes, rememberMeEnabled, devMode, demoMode, loginLogoLightUrl, loginLogoDarkUrl, loginCompanyName, loginImprintUrl, loginPrivacyPolicyUrl, loginWebsiteUrl, isLoading: configLoading, error: configError, autoSsoEnabled, embeddedMode: _embeddedMode, allowCustomJmapEndpoint, jmapServers, jmapServerAutoPickByDomain } = useConfig();
+  const { appName, jmapServerUrl: configuredServerUrl, oauthEnabled, oauthOnly, oauthClientId: globalOauthClientId, oauthIssuerUrl: globalOauthIssuerUrl, oauthScopes, rememberMeEnabled, devMode, demoMode, loginLogoLightUrl, loginLogoDarkUrl, loginCompanyName, loginImprintUrl, loginPrivacyPolicyUrl, loginWebsiteUrl, loginLogoMaxHeight, loginLogoMaxWidth, loginShowHeading, loginShowSubtitle, isLoading: configLoading, error: configError, autoSsoEnabled, embeddedMode: _embeddedMode, allowCustomJmapEndpoint, jmapServers, jmapServerAutoPickByDomain } = useConfig();
   const resolvedTheme = useThemeStore((s) => s.resolvedTheme);
 
+  // Login logo sizing: when a max height/width is configured, drop the fixed
+  // 64×64 box so the logo (e.g. a wide wordmark) can render at its true size.
+  const hasLogoSize = Boolean(loginLogoMaxHeight || loginLogoMaxWidth);
+  const loginLogoStyle = hasLogoSize
+    ? { maxHeight: loginLogoMaxHeight || undefined, maxWidth: loginLogoMaxWidth || undefined }
+    : undefined;
+
   const [formData, setFormData] = useState({
     username: "",
     password: "",
@@ -881,19 +888,24 @@ export default function LoginPage() {
         <div className="rounded-2xl border border-border/60 bg-background/80 backdrop-blur-sm shadow-xl shadow-black/5 dark:shadow-black/20 overflow-hidden">
           {/* Header section with logo */}
           <div className="px-8 pt-10 pb-6 text-center">
-            <div className="inline-flex items-center justify-center w-16 h-16 mb-5">
+            <div className={cn("inline-flex items-center justify-center mb-5", !hasLogoSize && "w-16 h-16")}>
               <img
                 src={withBasePath(resolvedTheme === 'dark' ? loginLogoDarkUrl : loginLogoLightUrl)}
                 alt={appName}
-                className="max-w-16 max-h-16 object-contain"
+                className={cn("object-contain", !hasLogoSize && "max-w-16 max-h-16")}
+                style={loginLogoStyle}
               />
             </div>
-            <h1 className="text-2xl font-semibold text-foreground tracking-tight">
-              {isAddAccountMode ? t("add_account_title") : appName}
-            </h1>
-            <p className="text-sm text-muted-foreground mt-1.5">
-              {isAddAccountMode ? t("add_account_subtitle") : (t("title") !== appName ? t("title") : "Sign in to your account")}
-            </p>
+            {loginShowHeading && (
+              <h1 className="text-2xl font-semibold text-foreground tracking-tight">
+                {isAddAccountMode ? t("add_account_title") : appName}
+              </h1>
+            )}
+            {loginShowSubtitle && (
+              <p className="text-sm text-muted-foreground mt-1.5">
+                {isAddAccountMode ? t("add_account_subtitle") : (t("title") !== appName ? t("title") : "Sign in to your account")}
+              </p>
+            )}
           </div>
 
           {/* Form section */}

app/api/config/route.ts

@@ -74,6 +74,10 @@ export async function GET(request: NextRequest) {
       loginImprintUrl: branded<string>('loginImprintUrl', ''),
       loginPrivacyPolicyUrl: branded<string>('loginPrivacyPolicyUrl', ''),
       loginWebsiteUrl: branded<string>('loginWebsiteUrl', ''),
+      loginLogoMaxHeight: configManager.get<string>('loginLogoMaxHeight', ''),
+      loginLogoMaxWidth: configManager.get<string>('loginLogoMaxWidth', ''),
+      loginShowHeading: configManager.get<boolean>('loginShowHeading', true),
+      loginShowSubtitle: configManager.get<boolean>('loginShowSubtitle', true),
       demoMode: configManager.get<boolean>('demoMode', false),
       allowCustomJmapEndpoint: configManager.get<boolean>('allowCustomJmapEndpoint', false),
       jmapServers: redactJmapServers(parseJmapServers(configManager.get<unknown>('jmapServers', []))),

hooks/use-config.ts

@@ -26,6 +26,10 @@ interface ConfigData {
   loginImprintUrl: string;
   loginPrivacyPolicyUrl: string;
   loginWebsiteUrl: string;
+  loginLogoMaxHeight: string;
+  loginLogoMaxWidth: string;
+  loginShowHeading: boolean;
+  loginShowSubtitle: boolean;
   demoMode: boolean;
   autoSsoEnabled: boolean;
   allowCustomJmapEndpoint: boolean;
@@ -105,6 +109,10 @@ export function useConfig(): AppConfig {
     loginImprintUrl: configCache?.loginImprintUrl || '',
     loginPrivacyPolicyUrl: configCache?.loginPrivacyPolicyUrl || '',
     loginWebsiteUrl: configCache?.loginWebsiteUrl || '',
+    loginLogoMaxHeight: configCache?.loginLogoMaxHeight || '',
+    loginLogoMaxWidth: configCache?.loginLogoMaxWidth || '',
+    loginShowHeading: configCache?.loginShowHeading ?? true,
+    loginShowSubtitle: configCache?.loginShowSubtitle ?? true,
     demoMode: configCache?.demoMode || false,
     autoSsoEnabled: configCache?.autoSsoEnabled || false,
     allowCustomJmapEndpoint: configCache?.allowCustomJmapEndpoint || false,
@@ -140,6 +148,10 @@ export function useConfig(): AppConfig {
         loginImprintUrl: configCache.loginImprintUrl,
         loginPrivacyPolicyUrl: configCache.loginPrivacyPolicyUrl,
         loginWebsiteUrl: configCache.loginWebsiteUrl,
+        loginLogoMaxHeight: configCache.loginLogoMaxHeight,
+        loginLogoMaxWidth: configCache.loginLogoMaxWidth,
+        loginShowHeading: configCache.loginShowHeading,
+        loginShowSubtitle: configCache.loginShowSubtitle,
         demoMode: configCache.demoMode,
         autoSsoEnabled: configCache.autoSsoEnabled,
         allowCustomJmapEndpoint: configCache.allowCustomJmapEndpoint,
@@ -176,6 +188,10 @@ export function useConfig(): AppConfig {
           loginImprintUrl: data.loginImprintUrl,
           loginPrivacyPolicyUrl: data.loginPrivacyPolicyUrl,
           loginWebsiteUrl: data.loginWebsiteUrl,
+          loginLogoMaxHeight: data.loginLogoMaxHeight,
+          loginLogoMaxWidth: data.loginLogoMaxWidth,
+          loginShowHeading: data.loginShowHeading,
+          loginShowSubtitle: data.loginShowSubtitle,
           demoMode: data.demoMode,
           autoSsoEnabled: data.autoSsoEnabled,
           allowCustomJmapEndpoint: data.allowCustomJmapEndpoint,

lib/admin/types.ts

@@ -166,6 +166,15 @@ export const CONFIG_ENV_MAP: Record<string, { envVar: string; fileEnvVar?: strin
   loginImprintUrl: { envVar: 'LOGIN_IMPRINT_URL', type: 'url', defaultValue: '' },
   loginPrivacyPolicyUrl: { envVar: 'LOGIN_PRIVACY_POLICY_URL', type: 'url', defaultValue: '' },
   loginWebsiteUrl: { envVar: 'LOGIN_WEBSITE_URL', type: 'url', defaultValue: '' },
+  // Login header customization. The logo box is otherwise a fixed 64×64
+  // (w-16/h-16), which fits a wide wordmark to ~13px tall; set a max height
+  // and/or width (any CSS length, e.g. "230px" or "3rem") to size it. The
+  // heading ({appName}) and subtitle can be hidden when the logo already
+  // reads as the brand (e.g. a wordmark) and they'd be redundant.
+  loginLogoMaxHeight: { envVar: 'LOGIN_LOGO_MAX_HEIGHT', type: 'string', defaultValue: '' },
+  loginLogoMaxWidth: { envVar: 'LOGIN_LOGO_MAX_WIDTH', type: 'string', defaultValue: '' },
+  loginShowHeading: { envVar: 'LOGIN_SHOW_HEADING', type: 'boolean', defaultValue: true },
+  loginShowSubtitle: { envVar: 'LOGIN_SHOW_SUBTITLE', type: 'boolean', defaultValue: true },
   oauthEnabled: { envVar: 'OAUTH_ENABLED', type: 'boolean', defaultValue: false },
   oauthOnly: { envVar: 'OAUTH_ONLY', type: 'boolean', defaultValue: false },
   oauthClientId: { envVar: 'OAUTH_CLIENT_ID', type: 'string', defaultValue: '' },