Initial commit: Phase 1 scaffolding complete

- Root package.json with concurrently for dev server
- Client: Vite + React 18 with design tokens and proxy config
- Server: Express with CORS, multer (20MB), Sharp resize
- Upload endpoint with preview generation
- Dockerfile (multi-stage) and docker-compose.yml
- Canvas deferred to Phase 8 (export functionality)

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

client/src/index.css

@@ -0,0 +1,68 @@
+:root {
+  /* Colors */
+  --accent: #38bdf8;
+  --accent-hover: #0ea5e9;
+  --accent-bg: rgba(56, 189, 248, 0.1);
+
+  /* Neutrals */
+  --bg-primary: #ffffff;
+  --bg-secondary: #f8fafc;
+  --bg-tertiary: #f1f5f9;
+  --border: #e2e8f0;
+  --border-focus: #38bdf8;
+  --text-primary: #0f172a;
+  --text-secondary: #475569;
+  --text-muted: #94a3b8;
+
+  /* Status colors */
+  --success: #22c55e;
+  --warning: #f59e0b;
+  --error: #ef4444;
+
+  /* Border radii */
+  --radius-sm: 4px;
+  --radius-md: 8px;
+  --radius-lg: 12px;
+  --radius-xl: 16px;
+
+  /* Shadows */
+  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
+  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
+  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
+
+  /* Typography */
+  --font-body: 'DM Sans', system-ui, -apple-system, sans-serif;
+  --font-mono: 'Space Mono', ui-monospace, Consolas, monospace;
+
+  font-family: var(--font-body);
+  line-height: 1.5;
+  font-weight: 400;
+  color: var(--text-primary);
+  background-color: var(--bg-primary);
+  font-synthesis: none;
+  text-rendering: optimizeLegibility;
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
+}
+
+* {
+  box-sizing: border-box;
+}
+
+body {
+  margin: 0;
+  min-height: 100vh;
+}
+
+#root {
+  min-height: 100vh;
+}
+
+button {
+  font-family: inherit;
+  cursor: pointer;
+}
+
+input, textarea, select {
+  font-family: inherit;
+}