Various clean-ups. Honestly I don't remember what I've done.

style.css

@@ -1,7 +1,7 @@
 * {
     margin: 0;
     padding: 0;
-    outline: 1px solid red;
+    #outline: 1px solid red;
 }
 
 .viewport {
@@ -42,8 +42,6 @@
 
 .nav_body {
     background-color: rgba(0, 0, 0, 50%);
-    list-style: none;
-    font-size: 100%;
     border-radius: 50cqh;
     height: auto;
     transition: 0.4s ease-out;
@@ -54,19 +52,21 @@
     transition: 0s ease-in;
 }
 
-.nav_menu .nav_title {
-    padding-left: 1cqw;
-    padding-right: 1cqw;
-    text-decoration: none;
+.nav_title {
+    text-decoration-line: none;
     color: lightpink;
     font-family: Arial, Helvetica, sans-serif;
     font-weight: bold;
-    transition: 0.4s ease-out;
     white-space: nowrap;
+    font-size: 100%;
+    padding-left: 1cqw;
+    padding-right: 1cqw;
+    transition: 0.4s ease-out;
     float: left;
+    text-transform: uppercase;
 }
 
-.nav_menu .nav_title:hover {
+.nav_title:hover {
     color: darkviolet;
     transition: 0s ease-in;
 }
@@ -91,6 +91,9 @@
 
 .dropdown_body {
     display: none;
+    border-bottom-left-radius: 1em;
+    border-bottom-right-radius: 1em;
+    background-color: rgba(0, 0, 0, 50%);
 }
 
 .dropdown:hover .dropdown_body {