refactor: enhance NewTrip styles for improved layout and responsiveness

src/styles/KoreaMap.css

@@ -2,11 +2,18 @@
   width: 100%;
   max-width: 400px;
   margin: 0 auto;
+  height: calc(100vh - 400px);
+  min-height: 300px;
+  max-height: 600px;
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
 }
 
 .korea-map-container svg {
   width: 100%;
-  height: auto;
+  height: 100%;
+  object-fit: contain;
 }
 
 .korea-map-container path {
@@ -24,3 +31,10 @@
 .korea-map-container path.selected {
   fill: #4a90e2;
 }
+
+@media screen and (max-width: 768px) {
+  .korea-map-container {
+    height: calc(100vh - 400px);
+    min-height: 300px;
+  }
+} 
\ No newline at end of file

src/styles/NewTrip.css

@@ -22,7 +22,6 @@
 
 .destination-selection,
 .date-selection {
-    flex: 1;
     display: flex;
     flex-direction: column;
     gap: 20px;