Initial commit — AI-powered coding tutor (Professor)

Next.js 16, React 19, Monaco editor, Anthropic SDK, multi-provider AI,
Wandbox Python execution, iframe HTML preview, SQLite auth + session persistence.

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

app/globals.css

@@ -0,0 +1,38 @@
+@import "tailwindcss";
+
+:root {
+  --background: #09090b;
+  --foreground: #fafafa;
+}
+
+html,
+body {
+  height: 100%;
+  overflow: hidden;
+  background: var(--background);
+  color: var(--foreground);
+}
+
+/* Scrollbar styling */
+* {
+  scrollbar-width: thin;
+  scrollbar-color: #3f3f46 transparent;
+}
+
+*::-webkit-scrollbar {
+  width: 6px;
+  height: 6px;
+}
+
+*::-webkit-scrollbar-track {
+  background: transparent;
+}
+
+*::-webkit-scrollbar-thumb {
+  background-color: #3f3f46;
+  border-radius: 3px;
+}
+
+*::-webkit-scrollbar-thumb:hover {
+  background-color: #52525b;
+}