diff --git a/resources/js/Pages/Courses/Player.tsx b/resources/js/Pages/Courses/Player.tsx
index b73af61..d207249 100644
--- a/resources/js/Pages/Courses/Player.tsx
+++ b/resources/js/Pages/Courses/Player.tsx
@@ -1,6 +1,6 @@
 import AuthenticatedLayout from '@/Layouts/AuthenticatedLayout';
 import { Head, Link, router } from '@inertiajs/react';
-import { useState, useEffect } from 'react';
+import { useState } from 'react';
 import { Plyr } from 'plyr-react';
 import 'plyr-react/plyr.css';
 import { 
@@ -68,6 +68,7 @@ interface CurrentLessonData {
     video_url: string | null;
     content_pdf: string | null;
     vocabularies: VocabularyData[];
+    is_completed?: boolean;
 }
 
 interface ProgressData {
@@ -83,6 +84,7 @@ interface PlayerProps {
     auth: {
         user: any;
     };
+    [key: string]: any;
 }
 
 // Helper to get YouTube video ID
@@ -93,33 +95,13 @@ function getYouTubeId(url: string | null): string | null {
     return (match && match[2].length === 11) ? match[2] : null;
 }
 
-export default function Player({ course, currentLesson, progress, auth }: PlayerProps) {
-    const [sidebarOpen, setSidebarOpen] = useState(true);
-    const [isPlaying, setIsPlaying] = useState<string | null>(null);
-
-    const handleComplete = () => {
-        router.post(route('lessons.complete', { lesson: currentLesson.id }));
-    };
-
-    const playAudio = (url: string, id: string) => {
-        const audio = new Audio(url);
-        setIsPlaying(id);
-        audio.play();
-        audio.onended = () => setIsPlaying(null);
-    };
-
-    const videoSource = currentLesson.video_url ? {
-        type: 'video' as const,
-        sources: [{
-            src: getYouTubeId(currentLesson.video_url) || currentLesson.video_url,
-            provider: currentLesson.video_url.includes('youtube') ? 'youtube' as const : 'html5' as const,
-        }],
-    } : null;
-
-    const NavigationContent = () => (
+/**
+ * Sub-component for Navigation Content
+ */
+function NavigationContent({ course, currentLesson }: { course: CourseData, currentLesson: CurrentLessonData }) {
+    return (
         <div className="space-y-6">
             <h3 className="text-xs font-black text-gray-400 uppercase tracking-widest pl-1">Daftar Materi</h3>
-            
             <div className="space-y-4">
                 {course.modules.map((module) => (
                     <div key={module.id} className="space-y-2">
@@ -131,6 +113,7 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                             {module.lessons.map((lesson) => (
                                 <li key={lesson.id}>
                                     <Link
+                                        // @ts-ignore
                                         href={route('courses.learn', { course: course.slug, lesson: lesson.slug })}
                                         className={`flex items-center gap-3 p-3 rounded-xl transition-all text-sm group ${
                                             lesson.id === currentLesson.id
@@ -159,13 +142,42 @@ export default function Player({ course, currentLesson, progress, auth }: Player
             </div>
         </div>
     );
+}
+
+export default function Player({ course, currentLesson, progress, auth }: PlayerProps) {
+    const [sidebarOpen, setSidebarOpen] = useState(true);
+    const [isPlaying, setIsPlaying] = useState<string | null>(null);
+
+    const handleComplete = () => {
+        // @ts-ignore
+        router.post(route('lessons.complete', { lesson: currentLesson.id }));
+    };
+
+    const playAudio = (url: string, id: string) => {
+        const audio = new Audio(url);
+        setIsPlaying(id);
+        audio.play();
+        audio.onended = () => setIsPlaying(null);
+    };
+
+    const videoSource = currentLesson.video_url ? {
+        type: 'video' as const,
+        sources: [{
+            src: getYouTubeId(currentLesson.video_url) || currentLesson.video_url,
+            provider: currentLesson.video_url.includes('youtube') ? 'youtube' as const : 'html5' as const,
+        }],
+    } : null;
 
     return (
         <AuthenticatedLayout
             header={
                 <div className="flex items-center justify-between gap-4 px-2 lg:px-0">
                     <div className="flex items-center gap-2 lg:gap-4 overflow-hidden">
-                        <Link href={route('courses.index')} className="p-2.5 rounded-xl bg-gray-50 hover:bg-white hover:shadow-md border border-gray-100 transition-all text-gray-500 hover:text-nihonbuzz-red shrink-0">
+                        <Link 
+                            // @ts-ignore
+                            href={route('courses.index')} 
+                            className="p-2.5 rounded-xl bg-gray-50 hover:bg-white hover:shadow-md border border-gray-100 transition-all text-gray-500 hover:text-nihonbuzz-red shrink-0"
+                        >
                             <ChevronLeft className="w-5 h-5" />
                         </Link>
                         <div className="overflow-hidden">
@@ -193,7 +205,7 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                                     <p className="text-xs text-nihonbuzz-red font-bold uppercase tracking-widest">Kurikulum Kursus</p>
                                 </SheetHeader>
                                 <div className="p-6 overflow-y-auto h-[calc(100vh-120px)]">
-                                    <NavigationContent />
+                                    <NavigationContent course={course} currentLesson={currentLesson} />
                                 </div>
                             </SheetContent>
                         </Sheet>
@@ -229,7 +241,7 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                                     {currentLesson.is_completed && <span className="px-2 py-0.5 bg-green-100 text-green-600 rounded-full">Completed</span>}
                                 </div>
                                 <h1 className="text-2xl lg:text-3xl font-black text-gray-900 leading-tight">
-                                    <FuriganaText text={currentLesson.title} />
+                                    <FuriganaText text={currentLesson.title || ''} />
                                 </h1>
                            </div>
                         </div>
@@ -237,10 +249,8 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                         {/* Text Content */}
                         {currentLesson.type === 'text' && currentLesson.content && (
                             <div className="bg-white p-8 lg:p-12 rounded-[40px] shadow-sm border border-gray-100">
-                                <article className="prose prose-nihonbuzz prose-lg lg:prose-xl max-w-none">
-                                    {/* Ideally we'd have a parser for the whole content HTML too, 
-                                        but for now we trust the seeder gives us plain text with furigana markers or HTML */}
-                                    <FuriganaText text={currentLesson.content} />
+                                <article className="prose prose-nihonbuzz prose-lg lg:prose-xl max-w-none font-medium text-gray-700 leading-relaxed">
+                                    <FuriganaText text={currentLesson.content || ''} />
                                 </article>
                             </div>
                         )}
@@ -250,14 +260,14 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                             <div className="aspect-[3/4] w-full rounded-[40px] overflow-hidden shadow-2xl ring-1 ring-black/5">
                                 <iframe
                                     src={currentLesson.content_pdf}
-                                    className="w-full h-full"
+                                    className="w-full h-full border-none"
                                     title={currentLesson.title}
                                 />
                             </div>
                         )}
 
                         {/* Vocabulary Section */}
-                        {currentLesson.vocabularies?.length > 0 && (
+                        {currentLesson.vocabularies && currentLesson.vocabularies.length > 0 && (
                             <div className="space-y-6">
                                 <div className="flex items-center gap-3">
                                     <div className="bg-nihonbuzz-red/10 p-2 rounded-2xl">
@@ -279,16 +289,16 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                                                     {isPlaying === vocab.id ? <Volume2 className="w-5 h-5 animate-pulse" /> : <Volume2 className="w-5 h-5" />}
                                                 </div>
                                                 <div>
-                                                    <FuriganaText text={vocab.word} className="text-lg font-black text-gray-900" />
+                                                    <FuriganaText text={vocab.word || ''} className="text-lg font-black text-gray-900" />
                                                     <div className="flex items-center gap-2 mt-0.5">
-                                                        <span className="text-xs font-bold text-nihonbuzz-red">{vocab.reading}</span>
-                                                        <span className="text-[10px] text-gray-400 uppercase font-black">{vocab.type}</span>
+                                                        <span className="text-xs font-bold text-nihonbuzz-red">{vocab.reading || ''}</span>
+                                                        <span className="text-[10px] text-gray-400 uppercase font-black">{vocab.type || ''}</span>
                                                     </div>
                                                 </div>
                                             </div>
                                             <div className="text-right pr-2">
-                                                <p className="font-bold text-gray-700">{vocab.meaning_id}</p>
-                                                <p className="text-[11px] text-gray-400">{vocab.romaji}</p>
+                                                <p className="font-bold text-gray-700">{vocab.meaning_id || ''}</p>
+                                                <p className="text-[11px] text-gray-400">{vocab.romaji || ''}</p>
                                             </div>
                                         </div>
                                     ))}
@@ -331,7 +341,7 @@ export default function Player({ course, currentLesson, progress, auth }: Player
                 {/* Sidebar - Desktop Navigation */}
                 <aside className={`fixed right-0 top-16 bottom-0 w-80 bg-white border-l border-gray-50 overflow-y-auto transition-all shadow-[-10px_0_30px_rgba(0,0,0,0.02)] ${sidebarOpen ? 'translate-x-0' : 'translate-x-full'} hidden lg:block z-10`}>
                     <div className="p-8 h-full flex flex-col">
-                        <NavigationContent />
+                        <NavigationContent course={course} currentLesson={currentLesson} />
                         
                         <div className="mt-auto pt-10">
                              <div className="bg-nihonbuzz-red/5 p-6 rounded-[32px] border border-nihonbuzz-red/10 text-center space-y-3 relative overflow-hidden group">
@@ -351,4 +361,3 @@ export default function Player({ course, currentLesson, progress, auth }: Player
         </AuthenticatedLayout>
     );
 }
-