diff --git a/__tests__/components/theme-toggle.test.tsx b/__tests__/components/theme-toggle.test.tsx
index 0f94f65..78e3e72 100644
--- a/__tests__/components/theme-toggle.test.tsx
+++ b/__tests__/components/theme-toggle.test.tsx
@@ -1,30 +1,59 @@
-import { describe, it, expect, vi } from 'vitest'
-import { render, screen, fireEvent } from '@testing-library/react'
+import { describe, expect, it, vi, afterEach } from 'vitest'
+import { render, screen } from '@testing-library/react'
+import { renderToString } from 'react-dom/server'
 import { ThemeToggle } from '@/components/ThemeToggle'
 
-const mockSetTheme = vi.fn()
-let currentTheme = 'system'
+const mockUseTheme = vi.fn()
 
 vi.mock('next-themes', () => ({
-  useTheme: () => ({
-    theme: currentTheme,
-    setTheme: mockSetTheme,
-  }),
+  useTheme: () => mockUseTheme(),
 }))
 
 describe('ThemeToggle', () => {
+  afterEach(() => {
+    vi.clearAllMocks()
+  })
+
+  it('renders nothing before mount', () => {
+    mockUseTheme.mockReturnValue({ theme: 'light', setTheme: vi.fn() })
+
+    expect(renderToString(<ThemeToggle />)).toBe('')
+  })
+
+  it('cycles light, dark, system, and light with the current theme label', async () => {
+    let theme = 'light'
+    const setTheme = vi.fn((nextTheme: string) => {
+      theme = nextTheme
+    })
+    mockUseTheme.mockImplementation(() => ({ theme, setTheme }))
+
+    const view = render(<ThemeToggle />)
+    const button = await screen.findByRole('button')
+
+    expect(button).toHaveAttribute('aria-label', 'Current theme: light. Click to switch.')
+
+    button.click()
+    expect(setTheme).toHaveBeenLastCalledWith('dark')
+    view.rerender(<ThemeToggle />)
+    expect(button).toHaveAttribute('aria-label', 'Current theme: dark. Click to switch.')
+
+    button.click()
+    expect(setTheme).toHaveBeenLastCalledWith('system')
+    view.rerender(<ThemeToggle />)
+    expect(button).toHaveAttribute('aria-label', 'Current theme: system. Click to switch.')
+
+    button.click()
+    expect(setTheme).toHaveBeenLastCalledWith('light')
+    view.rerender(<ThemeToggle />)
+    expect(button).toHaveAttribute('aria-label', 'Current theme: light. Click to switch.')
+  })
+
   it('renders a button with type="button"', () => {
+    mockUseTheme.mockReturnValue({ theme: 'system', setTheme: vi.fn() })
+
     render(<ThemeToggle />)
     const button = screen.getByRole('button')
     expect(button).toBeDefined()
     expect(button.getAttribute('type')).toBe('button')
   })
-
-  it('cycles through theme options on click', () => {
-    currentTheme = 'system'
-    render(<ThemeToggle />)
-    const button = screen.getByRole('button')
-    fireEvent.click(button)
-    expect(mockSetTheme).toHaveBeenCalledWith('light')
-  })
 })
diff --git a/components/ThemeToggle.tsx b/components/ThemeToggle.tsx
index fb015f5..925a6ce 100644
--- a/components/ThemeToggle.tsx
+++ b/components/ThemeToggle.tsx
@@ -12,7 +12,7 @@ export function ThemeToggle() {
 
   // Avoid hydration mismatch — only render after mount
   useEffect(() => setMounted(true), [])
-  if (!mounted) return <div className="w-9 h-9" />
+  if (!mounted) return null
 
   const cycle = () => {
     const idx = MODES.indexOf((theme as (typeof MODES)[number]) ?? 'system')
diff --git a/docs/adr/ADR-003-mock-mode.md b/docs/adr/ADR-003-mock-mode.md
index dc3759e..388bbaf 100644
--- a/docs/adr/ADR-003-mock-mode.md
+++ b/docs/adr/ADR-003-mock-mode.md
@@ -10,9 +10,9 @@ Developing against the live Soroban testnet requires a funded Freighter wallet,
 
 ## Decision
 
-The app supports a **mock contract layer** controlled by the `USE_MOCK` flag in `lib/contract.ts`. When enabled, all contract calls are intercepted and served from an in-memory store in `lib/mock-data.ts`. The mock layer implements the same TypeScript interface as the real contract integration so the rest of the app is unaware of the substitution.
+The app supports a **mock contract layer** that is automatically selected when the active network has no `NEXT_PUBLIC_STREAM_CONTRACT_ID_{NETWORK}` environment variable configured, as determined in `lib/contract.ts`. When no contract ID is set, contract calls are served from an in-memory store in `lib/mock-data.ts`. The mock layer implements the same TypeScript interface as the real contract integration so the rest of the app is unaware of the substitution.
 
-Mock mode is the default in development (`NODE_ENV === 'development'`) and is always disabled in production builds.
+Mock mode is active whenever the selected network has no contract ID configured, regardless of environment.
 
 ## Consequences
 
diff --git a/docs/cli-examples.md b/docs/cli-examples.md
index aa5689f..9be7e37 100644
--- a/docs/cli-examples.md
+++ b/docs/cli-examples.md
@@ -27,13 +27,7 @@ soroban contract invoke \
   -- \
   create_stream \
   --sender GXXXXXX... \
-  --recipient GYYYYYY... \
-  --token CTOKEN... \
-  --total_amount 1000000000 \
-  --start_time 1700000000 \
-  --end_time 1702592000 \
-  --cliff_time 1700000000 \
-  --cliff_amount 100000000
+  --params '{"recipient":"GYYYYYY...","token":"CTOKEN...","total_amount":1000000000,"start_time":1700000000,"end_time":1702592000,"cliff_time":1700000000,"cliff_amount":100000000}'
 ```
 
 ### 30-Day Monthly Salary Stream
@@ -54,13 +48,7 @@ soroban contract invoke \
   -- \
   create_stream \
   --sender $SENDER \
-  --recipient $RECIPIENT \
-  --token $TOKEN \
-  --total_amount $MONTHLY_SALARY \
-  --start_time $START \
-  --end_time $END \
-  --cliff_time $CLIFF \
-  --cliff_amount $((MONTHLY_SALARY / 4))
+  --params "{\"recipient\":\"$RECIPIENT\",\"token\":\"$TOKEN\",\"total_amount\":$MONTHLY_SALARY,\"start_time\":$START,\"end_time\":$END,\"cliff_time\":$CLIFF,\"cliff_amount\":$((MONTHLY_SALARY / 4))}"
 ```
 
 ### 1-Year Vesting with 6-Month Cliff
@@ -341,7 +329,7 @@ soroban contract invoke \
 # Process each row
 while IFS=',' read -r recipient amount start end cliff cliff_amt; do
   echo "Creating stream for $recipient..."
-  
+
   soroban contract invoke \
     --id $CONTRACT_ID \
     --source $USER_KEYPAIR \
@@ -355,7 +343,7 @@ while IFS=',' read -r recipient amount start end cliff cliff_amt; do
     --end_time $end \
     --cliff_time $cliff \
     --cliff_amount $cliff_amt
-  
+
   # Delay to avoid rate limiting
   sleep 2
 done < streams.csv
@@ -370,7 +358,7 @@ WITHDRAWAL_AMOUNT=100000000
 
 for STREAM_ID in "${STREAM_IDS[@]}"; do
   echo "Withdrawing from stream $STREAM_ID..."
-  
+
   soroban contract invoke \
     --id $CONTRACT_ID \
     --source $USER_KEYPAIR \
@@ -378,7 +366,7 @@ for STREAM_ID in "${STREAM_IDS[@]}"; do
     withdraw \
     --stream_id $STREAM_ID \
     --amount $WITHDRAWAL_AMOUNT
-  
+
   sleep 2
 done
 ```
@@ -488,24 +476,24 @@ while true; do
   echo "=== Stream #$STREAM_ID ==="
   echo "Updated at: $(date)"
   echo ""
-  
+
   STREAM=$(soroban contract invoke \
     --id $CONTRACT_ID \
     -- \
     get_stream \
     --stream_id $STREAM_ID)
-  
+
   echo "$STREAM" | jq '.'
-  
+
   echo ""
   WITHDRAWABLE=$(soroban contract invoke \
     --id $CONTRACT_ID \
     -- \
     get_withdrawable \
     --stream_id $STREAM_ID)
-  
+
   echo "Currently withdrawable: $WITHDRAWABLE"
-  
+
   sleep $INTERVAL
 done
 ```
diff --git a/lib/export.ts b/lib/export.ts
index 25c0504..d12f2f4 100644
--- a/lib/export.ts
+++ b/lib/export.ts
@@ -36,6 +36,10 @@ const HEADERS = [
   'Rate (per month)',
 ]
 
+/**
+ * Convert streams to CSV with identity, token, amount, date, cliff, and rate columns.
+ * A zero cliff time or cliff amount is represented by an empty CSV field.
+ */
 export function streamsToCSV(
   streams: StreamData[],
   nowSeconds: number = Math.floor(Date.now() / 1000),
@@ -78,6 +82,7 @@ export function streamsToCSV(
   return lines.join('\n')
 }
 
+/** Download CSV content as a file in the browser. */
 export function downloadCSV(csv: string, filename: string): void {
   const blob = new Blob([csv], { type: 'text/csv;charset=utf-8;' })
   const url = URL.createObjectURL(blob)