avoid hardcoding height for flex purposes

static/css/main.css

@@ -1,9 +1,3 @@
-@media only screen and (max-width: 850px) {
-    header#menu {
-        flex-direction: column !important;
-    }
-}
-
 :root {
     --main: #dd9a1a;
     --bg: #111;
@@ -34,7 +28,6 @@ div.main-content {
 header#menu {
     display: flex;
     flex-direction: row;
-    height: 3rem;
     border-width: 5px;
     border-color: var(--main);
     border-style: double;
@@ -42,6 +35,13 @@ header#menu {
     margin-bottom: 2rem;
 }
 
+@media (max-width: 850px) {
+    header#menu {
+        flex-direction: column;
+    }
+}
+
+
 header#menu a {
     padding: 12px;
     color: var(--main);