fix(machine): mobile UI polish and shadcn-vue ScrollArea

- Use h-dvh instead of h-screen for mobile browser viewport
- Add ScrollArea component (shadcn-vue) to replace native scrollbars
- Move Hide Debug into debug bar row, show Show Debug only when off
- Responsive cash-out denomination grid (single col on mobile)
- Add safe-area padding for mobile gesture bar
- Add business model documentation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/machine/src/App.vue

@@ -31,9 +31,7 @@ function toggleLiveServices() {
 </script>
 
 <template>
-  <div
-    class="flex h-screen w-screen flex-col overflow-hidden bg-background font-sans text-foreground"
-  >
+  <div class="flex h-dvh w-screen flex-col overflow-hidden bg-background font-sans text-foreground">
     <router-view />
 
     <!-- Connection status + balance (top right) -->
@@ -73,7 +71,7 @@ function toggleLiveServices() {
     <!-- Debug overlay (dev only) -->
     <div
       v-if="atmStore.debugMode"
-      class="shrink-0 bg-popover font-mono text-xs text-popover-foreground"
+      class="shrink-0 bg-popover pb-[env(safe-area-inset-bottom)] font-mono text-xs text-popover-foreground"
     >
       <div class="flex flex-wrap items-center gap-2 px-4 py-2 sm:gap-4">
         <Button
@@ -100,6 +98,14 @@ function toggleLiveServices() {
             {{ theme.label }}
           </Button>
         </div>
+        <Button
+          variant="ghost"
+          size="sm"
+          class="ml-auto h-6 text-xs text-muted-foreground"
+          @click="atmStore.toggleDebug"
+        >
+          Hide Debug
+        </Button>
       </div>
       <div v-if="debugExpanded" class="max-h-48 overflow-auto px-4 pb-4">
         <pre class="text-muted-foreground">{{ JSON.stringify(atmStore.context, null, 2) }}</pre>

apps/machine/src/components/ui/scroll-area/ScrollArea.vue

@@ -0,0 +1,29 @@
+<script setup lang="ts">
+import type { ScrollAreaRootProps } from 'reka-ui'
+import type { HTMLAttributes } from 'vue'
+import { reactiveOmit } from '@vueuse/core'
+import { ScrollAreaCorner, ScrollAreaRoot, ScrollAreaViewport } from 'reka-ui'
+import { cn } from '@/lib/utils'
+import ScrollBar from './ScrollBar.vue'
+
+const props = defineProps<ScrollAreaRootProps & { class?: HTMLAttributes['class'] }>()
+
+const delegatedProps = reactiveOmit(props, 'class')
+</script>
+
+<template>
+  <ScrollAreaRoot
+    data-slot="scroll-area"
+    v-bind="delegatedProps"
+    :class="cn('relative', props.class)"
+  >
+    <ScrollAreaViewport
+      data-slot="scroll-area-viewport"
+      class="focus-visible:ring-ring/50 size-full rounded-[inherit] transition-[color,box-shadow] outline-none focus-visible:ring-[3px] focus-visible:outline-1"
+    >
+      <slot />
+    </ScrollAreaViewport>
+    <ScrollBar />
+    <ScrollAreaCorner />
+  </ScrollAreaRoot>
+</template>

apps/machine/src/components/ui/scroll-area/ScrollBar.vue

@@ -0,0 +1,33 @@
+<script setup lang="ts">
+import type { ScrollAreaScrollbarProps } from 'reka-ui'
+import type { HTMLAttributes } from 'vue'
+import { reactiveOmit } from '@vueuse/core'
+import { ScrollAreaScrollbar, ScrollAreaThumb } from 'reka-ui'
+import { cn } from '@/lib/utils'
+
+const props = withDefaults(
+  defineProps<ScrollAreaScrollbarProps & { class?: HTMLAttributes['class'] }>(),
+  {
+    orientation: 'vertical',
+  }
+)
+
+const delegatedProps = reactiveOmit(props, 'class')
+</script>
+
+<template>
+  <ScrollAreaScrollbar
+    data-slot="scroll-area-scrollbar"
+    v-bind="delegatedProps"
+    :class="
+      cn(
+        'flex touch-none p-px transition-colors select-none',
+        orientation === 'vertical' && 'h-full w-2.5 border-l border-l-transparent',
+        orientation === 'horizontal' && 'h-2.5 flex-col border-t border-t-transparent',
+        props.class
+      )
+    "
+  >
+    <ScrollAreaThumb data-slot="scroll-area-thumb" class="bg-border relative flex-1 rounded-full" />
+  </ScrollAreaScrollbar>
+</template>

apps/machine/src/components/ui/scroll-area/index.ts

@@ -0,0 +1,2 @@
+export { default as ScrollArea } from './ScrollArea.vue'
+export { default as ScrollBar } from './ScrollBar.vue'

apps/machine/src/views/CashInView.vue

@@ -8,6 +8,7 @@ import { Badge } from '@/components/ui/badge'
 import { Alert, AlertDescription } from '@/components/ui/alert'
 import { Skeleton } from '@/components/ui/skeleton'
 import { Input } from '@/components/ui/input'
+import { ScrollArea } from '@/components/ui/scroll-area'
 import QRCode from '@/components/QRCode.vue'
 import BitcoinIcon from '@/components/BitcoinIcon.vue'
 
@@ -196,9 +197,8 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
     </header>
 
     <!-- Content -->
-    <main
-      class="flex min-h-0 flex-1 items-start justify-center overflow-auto p-4 sm:items-center sm:p-8"
-    >
+    <ScrollArea class="min-h-0 flex-1">
+      <main class="flex min-h-0 flex-1 items-start justify-center p-4 sm:items-center sm:p-8">
         <!-- Fetching Rate -->
         <Card v-if="nestedState === 'fetchingRate'" class="w-full max-w-80 border-0 bg-white/5">
           <CardContent class="flex flex-col items-center gap-4 p-8">
@@ -223,7 +223,9 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
             <div v-if="context" class="rounded-lg bg-white/5 p-4">
               <div class="mb-2 flex justify-between">
                 <span class="text-muted-foreground">Inserted:</span>
-              <span class="text-2xl font-bold text-green-400">${{ context.fiatAmount / 100 }}</span>
+                <span class="text-2xl font-bold text-green-400"
+                  >${{ context.fiatAmount / 100 }}</span
+                >
               </div>
               <div class="flex justify-between">
                 <span class="text-muted-foreground">You'll receive:</span>
@@ -234,7 +236,10 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
             </div>
 
             <!-- Available balance indicator -->
-          <div v-if="context && context.availableBalance > 0" class="flex justify-between text-sm">
+            <div
+              v-if="context && context.availableBalance > 0"
+              class="flex justify-between text-sm"
+            >
               <span class="text-muted-foreground">Available:</span>
               <span :class="balanceLimitReached ? 'text-foreground' : 'text-muted-foreground'">
                 {{ formatSats(context.availableBalance) }} sats
@@ -460,7 +465,10 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
         </Card>
 
         <!-- Ask for Receipt -->
-      <Card v-else-if="nestedState === 'askForReceipt'" class="w-full max-w-80 border-0 bg-white/5">
+        <Card
+          v-else-if="nestedState === 'askForReceipt'"
+          class="w-full max-w-80 border-0 bg-white/5"
+        >
           <CardContent class="flex flex-col items-center gap-4 p-8">
             <div class="text-6xl text-green-400">✅</div>
             <CardTitle>Payment Sent!</CardTitle>
@@ -484,7 +492,10 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
         </Card>
 
         <!-- Complete -->
-      <Card v-else-if="nestedState === 'complete'" class="w-full max-w-80 border-0 bg-green-900/30">
+        <Card
+          v-else-if="nestedState === 'complete'"
+          class="w-full max-w-80 border-0 bg-green-900/30"
+        >
           <CardContent class="flex flex-col items-center gap-4 p-8 text-center">
             <div class="text-6xl">🎉</div>
             <CardTitle class="text-green-400">Transaction Complete!</CardTitle>
@@ -502,7 +513,10 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
             <div class="text-6xl">⚠️</div>
             <CardTitle class="text-red-400">Error</CardTitle>
             <p class="text-muted-foreground">{{ context?.error || 'An error occurred' }}</p>
-          <Button class="bg-gradient-to-r from-orange-500 to-yellow-400 text-black" @click="cancel">
+            <Button
+              class="bg-gradient-to-r from-orange-500 to-yellow-400 text-black"
+              @click="cancel"
+            >
               Return to Start
             </Button>
           </CardContent>
@@ -515,5 +529,6 @@ const isProcessing = computed(() => atmStore.isPayingInvoice || atmStore.isReque
           </CardContent>
         </Card>
       </main>
+    </ScrollArea>
   </div>
 </template>

apps/machine/src/views/CashOutView.vue

@@ -7,6 +7,7 @@ import { Card, CardContent, CardHeader, CardTitle, CardDescription } from '@/com
 import { Badge } from '@/components/ui/badge'
 import { Alert, AlertDescription } from '@/components/ui/alert'
 import { Skeleton } from '@/components/ui/skeleton'
+import { ScrollArea } from '@/components/ui/scroll-area'
 import QRCode from '@/components/QRCode.vue'
 
 const router = useRouter()
@@ -105,9 +106,8 @@ function formatFiat(cents: number): string {
     </header>
 
     <!-- Content -->
-    <main
-      class="flex min-h-0 flex-1 items-start justify-center overflow-auto p-4 sm:items-center sm:p-8"
-    >
+    <ScrollArea class="min-h-0 flex-1">
+      <main class="flex min-h-0 flex-1 items-start justify-center p-4 sm:items-center sm:p-8">
         <!-- Fetching Rate -->
         <Card v-if="nestedState === 'fetchingRate'" class="w-full max-w-80 border-0 bg-white/5">
           <CardContent class="flex flex-col items-center gap-4 p-8">
@@ -129,26 +129,30 @@ function formatFiat(cents: number): string {
           </CardHeader>
           <CardContent class="space-y-6">
             <!-- Denomination buttons -->
-          <div class="grid grid-cols-2 gap-4">
+            <div class="grid grid-cols-1 gap-3 sm:grid-cols-2 sm:gap-4">
               <div
                 v-for="denom in availableDenominations"
                 :key="denom"
-              class="flex items-center justify-between rounded-lg bg-white/5 p-4"
+                class="flex items-center justify-between rounded-lg bg-white/5 px-4 py-3 sm:p-4"
               >
-              <span class="text-2xl font-bold text-green-400">${{ denom }}</span>
-              <div class="flex items-center gap-2">
+                <span class="text-xl font-bold text-green-400 sm:text-2xl">${{ denom }}</span>
+                <div class="flex items-center gap-3">
                   <Button
                     variant="outline"
                     size="sm"
+                    class="h-9 w-9"
                     :disabled="!canRemove(denom)"
                     @click="atmStore.removeDenomination(denom)"
                   >
                     -
                   </Button>
-                <span class="w-8 text-center text-lg">{{ selectionCounts[denom] || 0 }}</span>
+                  <span class="w-8 text-center text-lg font-medium">{{
+                    selectionCounts[denom] || 0
+                  }}</span>
                   <Button
                     variant="outline"
                     size="sm"
+                    class="h-9 w-9"
                     :disabled="!canAdd(denom)"
                     @click="atmStore.addDenomination(denom)"
                   >
@@ -305,10 +309,15 @@ function formatFiat(cents: number): string {
         </Card>
 
         <!-- Ask for Receipt -->
-      <Card v-else-if="nestedState === 'askForReceipt'" class="w-full max-w-80 border-0 bg-white/5">
+        <Card
+          v-else-if="nestedState === 'askForReceipt'"
+          class="w-full max-w-80 border-0 bg-white/5"
+        >
           <CardContent class="flex flex-col items-center gap-4 p-8">
             <CardTitle>Would you like a receipt?</CardTitle>
-          <p class="text-sm text-muted-foreground">Scan your npub to receive a Nostr DM receipt</p>
+            <p class="text-sm text-muted-foreground">
+              Scan your npub to receive a Nostr DM receipt
+            </p>
             <div class="flex h-32 w-32 items-center justify-center rounded-lg bg-white">
               <p class="text-black">📱 Scan npub</p>
             </div>
@@ -317,7 +326,10 @@ function formatFiat(cents: number): string {
         </Card>
 
         <!-- Complete -->
-      <Card v-else-if="nestedState === 'complete'" class="w-full max-w-80 border-0 bg-green-900/30">
+        <Card
+          v-else-if="nestedState === 'complete'"
+          class="w-full max-w-80 border-0 bg-green-900/30"
+        >
           <CardContent class="flex flex-col items-center gap-4 p-8 text-center">
             <div class="text-6xl">🎉</div>
             <CardTitle class="text-green-400">Transaction Complete!</CardTitle>
@@ -334,7 +346,10 @@ function formatFiat(cents: number): string {
             <div class="text-6xl">⚠️</div>
             <CardTitle class="text-red-400">Error</CardTitle>
             <p class="text-muted-foreground">{{ context?.error || 'An error occurred' }}</p>
-          <Button class="bg-gradient-to-r from-orange-500 to-yellow-400 text-black" @click="cancel">
+            <Button
+              class="bg-gradient-to-r from-orange-500 to-yellow-400 text-black"
+              @click="cancel"
+            >
               Return to Start
             </Button>
           </CardContent>
@@ -347,5 +362,6 @@ function formatFiat(cents: number): string {
           </CardContent>
         </Card>
       </main>
+    </ScrollArea>
   </div>
 </template>

apps/machine/src/views/IdleView.vue

@@ -59,7 +59,9 @@ function handleCashOut() {
 </script>
 
 <template>
-  <div class="flex flex-1 flex-col items-center justify-center gap-4 p-4 sm:gap-6 md:gap-8 md:p-8">
+  <div
+    class="flex min-h-0 flex-1 flex-col items-center justify-center gap-4 overflow-auto p-4 sm:gap-6 md:gap-8 md:p-8"
+  >
     <!-- Logo -->
     <div class="flex flex-col items-center gap-1 sm:gap-2">
       <img
@@ -187,14 +189,15 @@ function handleCashOut() {
       </div>
     </div>
 
-    <!-- Debug toggle -->
+    <!-- Debug toggle (only visible when debug bar is hidden) -->
     <Button
+      v-if="!atmStore.debugMode"
       variant="ghost"
       size="sm"
       class="absolute bottom-4 right-4 text-xs text-muted-foreground"
       @click="atmStore.toggleDebug"
     >
-      {{ atmStore.debugMode ? 'Hide Debug' : 'Show Debug' }}
+      Show Debug
     </Button>
   </div>
 </template>

docs/business-model.md

@@ -0,0 +1,121 @@
+# Business Model
+
+How we place ATMs at locations and make them sustainable for everyone involved.
+
+## Principles
+
+- **No KYC** — more users, less friction, preserves privacy
+- **Good energy locations** — we seek places with community trust and genuine intent
+- **Bitcoin-native infrastructure** — Lightning, Nostr, Cashu — no legacy payment rails
+- **Operator sovereignty** — locations can choose how much they want to manage themselves
+
+## Deployment Models
+
+### Managed (we run it)
+
+We own the machine and handle all operations. The location provides power, internet, and floor space.
+
+| Aspect              | Details                                   |
+| ------------------- | ----------------------------------------- |
+| Machine ownership   | Us                                        |
+| Liquidity           | Our Lightning channels + cash servicing   |
+| Software updates    | Us (remote via Nostr)                     |
+| Cash management     | Us (periodic servicing visits)            |
+| Fee configuration   | Us                                        |
+| Revenue to location | Fixed monthly hosting fee OR % of tx fees |
+
+Best for locations that want passive income with zero involvement.
+
+### Self-Sovereign (they run it)
+
+The location buys (or finances) the machine and runs their own stack.
+
+| Aspect            | Details                                  |
+| ----------------- | ---------------------------------------- |
+| Machine ownership | Them                                     |
+| Liquidity         | Their own Lightning node + Lightning.Pub |
+| Software updates  | Them (we provide releases)               |
+| Cash management   | Them                                     |
+| Fee configuration | Them                                     |
+| Revenue           | 100% theirs                              |
+
+Best for bitcoiners who want to run infrastructure and keep full control. We provide the software, hardware, and support.
+
+### Machine Financing
+
+For the self-sovereign model, we can offer financing:
+
+- We purchase the machine upfront
+- Location pays it off over time (from ATM revenue)
+- Once paid off, they own it outright
+- We provide support during the financing period
+
+## Revenue Models
+
+### Fixed Hosting Fee
+
+- We pay the location a flat monthly fee for hosting
+- Simpler accounting, predictable income for location
+- We take all transaction fee revenue
+- Works well for locations that just want passive income
+
+### Profit Sharing
+
+- Location receives a % of transaction fees
+- Aligns incentives — they benefit from higher volume
+- More attractive to engaged locations
+- Requires transparent reporting (could be on-chain/Nostr-verifiable)
+
+### Foot Traffic Value
+
+Beyond direct revenue, the ATM provides:
+
+- People visit specifically to use the ATM, then browse/buy at the location
+- Bitcoin-friendly branding signals to the community
+- Conversation starter — draws curious newcomers
+- Community hub potential — meetup anchor point
+
+## Location Criteria
+
+We're selective about where we place machines. The goal is to find locations with **good energy** — places where the community is genuine and the environment discourages misuse.
+
+### Ideal locations
+
+- Coffee shops, cafes, local restaurants
+- Co-working spaces, maker spaces
+- Bitcoin meetup venues, hackerspaces
+- Surf shops, yoga studios, wellness centers
+- Local/independent businesses (not chains)
+- Places where the owner is curious about or already into Bitcoin
+
+### What we look for
+
+- Owner alignment — understands or wants to understand Bitcoin
+- Community trust — regulars know each other, self-policing
+- Foot traffic — enough people to make the machine worthwhile
+- Stable internet + power
+- Visible but not exposed — inside the business, not on the street
+
+### What we avoid
+
+- High-crime areas
+- Anonymous/transient locations (gas stations on highways, etc.)
+- Businesses with no community connection
+- Anywhere the owner is purely financially motivated with no alignment
+
+## Technical Requirements
+
+For the managed model to work at scale, we need:
+
+- **Remote monitoring** — machine status, cash levels, error alerts over [[clink-protocol|CLINK]]/Nostr
+- **Operator dashboard** — manage cassettes, view transactions, update config remotely
+- **Multi-machine support** — one Lightning.Pub instance serving multiple ATMs
+- **Fee configuration** — per-machine fee % set by operator
+- **Availability broadcast** — public Nostr events indicating cash-in/cash-out availability (see [[ndebit-cash-in-flow|cash-in flow]])
+
+## Related
+
+- [[device-configuration]] — hardware setup for different machine models
+- [[machine-installation]] — NixOS installation on ATM hardware
+- [[clink-protocol]] — CLINK protocol for ATM-wallet communication
+- [[ndebit-cash-in-flow]] — cash-in payment flow