diff --git a/.gitignore b/.gitignore
index 7c24f20..e442b33 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,13 @@
 # npm
 node_modules
+package-lock.json # repo pakai yarn.lock, jangan commit keduanya
 
 # clasp files
 creds.json
+# multi-account: token OAuth + scriptId per env, JANGAN commit
+.clasprc*.json
+.clasp.json
+.clasp.*.json
 
 # certs
 *.pem
diff --git a/Use-Clasp.ps1 b/Use-Clasp.ps1
new file mode 100644
index 0000000..c080b8c
--- /dev/null
+++ b/Use-Clasp.ps1
@@ -0,0 +1,48 @@
+#Requires -Version 5.1
+<#
+.SYNOPSIS
+  Aktifkan salah satu akun clasp (dev / prod / bdn) dengan swap file kredensial global.
+.DESCRIPTION
+  clasp hanya mengenal SATU login global (%USERPROFILE%\.clasprc.json) dan tidak
+  punya flag --local (terverifikasi di clasp 2.5.0). Skrip ini meng-copy profil
+  tersimpan (.clasp-accounts\<env>.clasprc.json) menjadi login aktif, lalu
+  verifikasi dengan `clasp login --status`.
+.EXAMPLE
+  powershell -NoProfile -ExecutionPolicy Bypass -File .\Use-Clasp.ps1 dev
+#>
+param(
+  [ValidateSet("dev", "prod", "bdn")]
+  [string]$Account = "dev"
+)
+
+$ErrorActionPreference = "Stop"
+
+$profileDir = Join-Path $env:USERPROFILE ".clasp-accounts"
+$src = Join-Path $profileDir ("$Account.clasprc.json")
+$dst = Join-Path $env:USERPROFILE ".clasprc.json"
+
+if (-not (Test-Path -LiteralPath $src)) {
+  Write-Output "Profil '$Account' belum ada: $src"
+  Write-Output "Cara buat (sekali per akun):"
+  Write-Output "  1. clasp login   # login sebagai akun-$Account di browser"
+  Write-Output "  2. New-Item -ItemType Directory -Force '$profileDir'"
+  Write-Output "  3. Copy-Item '$dst' '$src'"
+  exit 1
+}
+
+Copy-Item -LiteralPath $src -Destination $dst -Force
+Write-Output "Akun clasp aktif: $Account"
+
+$claspCmd = Get-Command clasp -ErrorAction SilentlyContinue
+if (-not $claspCmd) {
+  $localClasp = Join-Path $PSScriptRoot "node_modules/.bin/clasp.ps1"
+  if (Test-Path -LiteralPath $localClasp) { $claspCmd = $localClasp }
+  else { $claspCmd = "clasp" }
+}
+
+& $claspCmd login --status
+if ($LASTEXITCODE -ne 0) {
+  Write-Output "Token profil '$Account' tidak valid/kadaluarsa."
+  Write-Output "Perbaiki: clasp login (sebagai akun-$Account), lalu Copy-Item '$dst' '$src' -Force"
+  exit 1
+}
diff --git a/package.json b/package.json
index f9e484c..55ffe72 100644
--- a/package.json
+++ b/package.json
@@ -17,6 +17,9 @@
     "setup": "rimraf .clasp.json && mkdirp dist && clasp create --type sheets --title \"My React Project\" --rootDir ./dist && mv ./dist/.clasp.json ./.clasp.json && rimraf dist",
     "open": "clasp open --addon",
     "push": "clasp push",
+    "use:dev": "powershell -NoProfile -ExecutionPolicy Bypass -File ./Use-Clasp.ps1 dev",
+    "use:prod": "powershell -NoProfile -ExecutionPolicy Bypass -File ./Use-Clasp.ps1 prod",
+    "use:bdn": "powershell -NoProfile -ExecutionPolicy Bypass -File ./Use-Clasp.ps1 bdn",
     "setup:https": "mkdirp certs && mkcert -key-file ./certs/key.pem -cert-file ./certs/cert.pem localhost 127.0.0.1",
     "build:dev": "tsc && vite build --mode development",
     "build": "tsc && vite build --mode production",
diff --git a/scripts/clasp-env.ps1 b/scripts/clasp-env.ps1
new file mode 100644
index 0000000..3de95d8
--- /dev/null
+++ b/scripts/clasp-env.ps1
@@ -0,0 +1,67 @@
+#Requires -Version 5.1
+<#
+.SYNOPSIS
+  Wrapper satu pintu untuk clasp tiga akun + tiga project (dev / prod / bdn).
+.DESCRIPTION
+  Urutan kerja: swap akun (Use-Clasp.ps1) -> salin .clasp.<env>.json menjadi
+  .clasp.json -> guard khusus prod -> jalankan clasp. Jangan panggil
+  `clasp push` langsung; selalu lewat wrapper ini / npm script.
+.EXAMPLE
+  powershell -NoProfile -ExecutionPolicy Bypass -File .\scripts\clasp-env.ps1 -Env dev -Cmd use
+  powershell -NoProfile -ExecutionPolicy Bypass -File .\scripts\clasp-env.ps1 -Env dev -Cmd push
+  powershell -NoProfile -ExecutionPolicy Bypass -File .\scripts\clasp-env.ps1 -Env prod -Cmd push
+#>
+param(
+  [ValidateSet("dev", "prod", "bdn")]
+  [string]$Env = "dev",
+  [ValidateSet("use", "push")]
+  [string]$Cmd = "use"
+)
+
+$ErrorActionPreference = "Stop"
+$repoRoot = Split-Path $PSScriptRoot -Parent
+
+# 1. Aktifkan akun yang sesuai (berhenti bila profil/token bermasalah).
+& powershell -NoProfile -ExecutionPolicy Bypass -File (Join-Path $repoRoot "Use-Clasp.ps1") $Env
+if ($LASTEXITCODE -ne 0) { exit 1 }
+
+# 2. Arahkan ke project script yang sesuai.
+$projectFile = Join-Path $repoRoot ".clasp.$Env.json"
+$activeFile = Join-Path $repoRoot ".clasp.json"
+if (-not (Test-Path -LiteralPath $projectFile)) {
+  Write-Output "File project belum ada: $projectFile"
+  Write-Output "Cara buat: clasp create --type sheets --title ... --rootDir ./dist"
+  Write-Output "lalu isi scriptId project-$Env, atau copy dari .clasp.json.SAMPLE"
+  exit 1
+}
+Copy-Item -LiteralPath $projectFile -Destination $activeFile -Force
+
+$scriptId = (Get-Content -LiteralPath $activeFile -Raw | ConvertFrom-Json).scriptId
+Write-Output "Project aktif [$Env]: $scriptId"
+
+if ($Cmd -eq "use") {
+  Write-Output "Siap. Perintah clasp berikutnya memakai akun-$Env + project-$Env."
+  exit 0
+}
+
+# 3. Guard prod/bdn: wajib konfirmasi eksplisit.
+if ($Env -eq "prod" -or $Env -eq "bdn") {
+  $need = $Env.ToUpper()
+  $answer = Read-Host "Ketik $need untuk push ke PROYEK $need ($scriptId)"
+  if ($answer -cne $need) {
+    Write-Output "Dibatalkan. Tidak ada yang di-push."
+    exit 1
+  }
+}
+
+# 4. Push (build dulu agar dist/ selalu segar dari src/).
+Push-Location $repoRoot
+try {
+  & npm run build
+  if ($LASTEXITCODE -ne 0) { exit 1 }
+  & clasp push
+  exit $LASTEXITCODE
+}
+finally {
+  Pop-Location
+}