diff --git a/pages/index.vue b/pages/studio-1.vue
similarity index 100%
rename from pages/index.vue
rename to pages/studio-1.vue
diff --git a/utils/music.ts b/utils/music.ts
index 9c329df..ff9e07c 100644
--- a/utils/music.ts
+++ b/utils/music.ts
@@ -1,5 +1,5 @@
 export const MUSIC_DURATION_MIN = 30
-export const MUSIC_DURATION_MAX = 180
+export const MUSIC_DURATION_MAX = 150
 export const MUSIC_DURATION_DEFAULT = 60
 export const MUSIC_STEPS_MIN = 8
 export const MUSIC_STEPS_MAX = 100
@@ -33,27 +33,18 @@ export const DEFAULT_MUSIC_LYRICS = `[Verse 1]
 [Outro]
 `
 
-export type MusicEngine = 'ace-step' | 'ace-step-1.5' | 'yue' | 'yue2'
+export type MusicEngine = 'yue2'
 
 export function parseMusicEngine(raw: unknown): MusicEngine {
   const value = String(raw || '').trim().toLowerCase()
-  if (value === 'ace-step-1.5' || value === 'ace15' || value === 'v1.5') return 'ace-step-1.5'
-  if (value === 'yue2' || value === 'yue-2') return 'yue2'
-  if (value === 'yue' || value === 'yue-s1' || value === 'lyrics2song') return 'yue'
-  return 'ace-step'
-}
-
-export function isAceMusicEngine(engine: MusicEngine | string | undefined) {
-  const value = parseMusicEngine(engine)
-  return value !== 'yue' && value !== 'yue2'
+  if (value === 'yue2' || value === 'yue-2' || !value) return 'yue2'
+  // Legacy ACE / YuEGP values map to YuE2 — the only supported music engine.
+  return 'yue2'
 }
 
 export function musicEngineLabel(engine: MusicEngine | string | undefined) {
-  const value = parseMusicEngine(engine)
-  if (value === 'ace-step-1.5') return 'ACE-Step 1.5'
-  if (value === 'yue2') return 'YuE2'
-  if (value === 'yue') return 'YuE'
-  return 'ACE-Step'
+  void engine
+  return 'YuE2'
 }
 
 export function parseMusicBpm(tags: unknown, fallback = 120) {
@@ -97,18 +88,17 @@ export function sanitizeMusicLyrics(raw: unknown, instrumental = false) {
   return String(raw || '').replace(/\r\n/g, '\n').trim().slice(0, MUSIC_LYRICS_MAX)
 }
 
-/** YuE splits on [Section] headers. Returns how many sections are present. */
+/** YuE2 splits on [Section] headers. Returns how many section tags are present. */
 export function countYueLyricSections(lyrics: unknown) {
   const text = String(lyrics || '')
   const matches = text.match(/\[[^\]]+\]/g)
   return matches ? matches.length : 0
 }
 
+/** YuE2 allows multiple lyric sections; only empty lyrics are rejected. */
 export function yueLyricsProblem(lyrics: unknown): string | null {
   const text = String(lyrics || '').trim()
-  if (!text) return 'YuE needs lyrics with section tags like [Verse 1] and [Chorus].'
-  const sections = [...text.matchAll(/\[([^\]]+)\]\s*([^\[]*)/gs)].filter(match => match[2].trim())
-  if (sections.length !== 1) return 'YuEGP needs exactly one non-empty lyric section. Combine the lyrics under one heading.'
+  if (!text) return 'YuE2 needs lyrics. Use section tags like [Verse 1] and [Chorus] when you want structure.'
   return null
 }