feat: changed default font to Pretendard

assets/css/style.scss

@@ -3,8 +3,14 @@
 
 @import '{{ site.theme }}';
 
+@import url("https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.8/dist/web/static/pretendard.css");
+
 /* append your custom style below */
 
 footer p:last-child::before {
     content: none;
 }
+
+* {
+    font-family: Pretendard;
+}