feat: implement core course platform UI and logic

- Add project configuration and git ignore rules
- Implement App router with protected routes
- Develop course player, grid, and card components
- Add state management for course progress and navigation
- Initialize database services for course and comment data

index.css

@@ -0,0 +1,84 @@
+:root {
+  /* Typography Tokens */
+  --font-display: "Manrope", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+  --font-body: "Manrope", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
+
+  /* Border Radii */
+  --radius-tag: 980px;
+  --radius-button: 980px;
+  --radius-card: 8px;
+  --radius-image: 8px;
+  --radius-input: 8px;
+
+  /* Shadows */
+  --shadow-xl: 0 10px 30px -5px rgba(0, 0, 0, 0.3);
+
+  /* Layout */
+  --page-max-width: 1440px;
+}
+
+body {
+  font-family: var(--font-body);
+  background-color: #000000;
+  color: #f4f4f5;
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
+}
+
+h1, h2, h3, h4, h5, h6, .font-display, .font-heading {
+  font-family: var(--font-display);
+}
+
+/* Hide scrollbar for Chrome, Safari and Opera */
+.hide-scrollbar::-webkit-scrollbar {
+  display: none;
+}
+
+/* Hide scrollbar for IE, Edge and Firefox */
+.hide-scrollbar {
+  -ms-overflow-style: none;  /* IE and Edge */
+  scrollbar-width: none;  /* Firefox */
+}
+
+/* Custom scrollbar for modals & panels */
+::-webkit-scrollbar {
+  width: 6px;
+  height: 6px;
+}
+
+::-webkit-scrollbar-track {
+  background: #09090b;
+}
+
+::-webkit-scrollbar-thumb {
+  background: #27272a;
+  border-radius: 980px;
+}
+
+::-webkit-scrollbar-thumb:hover {
+  background: #3f3f46;
+}
+
+/* Smooth drag cursor */
+.cursor-grab {
+  cursor: grab;
+}
+.cursor-grabbing {
+  cursor: grabbing;
+  user-select: none;
+}
+
+@keyframes fadeInUp {
+  from {
+    opacity: 0;
+    transform: translateY(12px);
+  }
+  to {
+    opacity: 1;
+    transform: translateY(0);
+  }
+}
+
+.animate-fade-in-up {
+  animation: fadeInUp 0.35s cubic-bezier(0.16, 1, 0.3, 1) forwards;
+}