feat: PostCard 컴포넌트 스타일 개선 및 텍스트 오버플로우 처리

Author: yurim

fundamentals/today-i-learned/src/components/features/discussions/PostCard.tsx

@@ -250,15 +250,21 @@ const postTitle = css({
   letterSpacing: "-0.4px",
   color: "#0F0F0F",
   transition: "colors 0.15s ease-in-out",
+  overflow: "hidden",
+  textOverflow: "ellipsis",
+  whiteSpace: "nowrap",
   _hover: {
     color: "rgb(55, 65, 81)"
   }
 });
 
 const contentPreview = css({
   display: "-webkit-box",
-  WebkitLineClamp: "2",
+  WebkitLineClamp: "3",
+  // @ts-ignore
+  WebkitBoxOrient: "vertical",
   overflow: "hidden",
+  textOverflow: "ellipsis",
   transition: "colors 0.15s ease-in-out",
   _hover: {
     color: "rgba(0, 0, 0, 0.6)"