Reduce blur on locked course cards for readability

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/(student)/dashboard/page.tsx

@@ -178,7 +178,7 @@ export default async function StudentDashboard() {
                   </span>
                 </div>
                 {/* Размытый контент карточки */}
-                <div className="flex flex-col flex-1" style={{ filter: "blur(3px)", opacity: 0.7, pointerEvents: "none" }}>
+                <div className="flex flex-col flex-1" style={{ filter: "blur(1.8px)", opacity: 0.82, pointerEvents: "none" }}>
                   {course.coverImage ? (
                     // eslint-disable-next-line @next/next/no-img-element
                     <img src={course.coverImage} alt={course.title} className="w-full aspect-video object-cover" />