style: apply genre grid layout and improve form spacing

static/style.css

@@ -4,13 +4,14 @@ body {
   display: flex;
   justify-content: center;
   align-items: center;
-  height: 100vh;
+  min-height: 100vh;
   margin: 0;
 }
 
 form {
   background-color: #fff;
   padding: 30px 40px;
+  margin: 30px 40px;
   border-radius: 10px;
   box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
   max-width: 400px;
@@ -108,3 +109,10 @@ button:hover {
     color: blue;
     cursor: pointer;
 }
+
+.genre-grid {
+    display: grid;
+    grid-template-columns: 1fr 1fr;
+    gap: 0.5rem;
+    margin-bottom: 1rem;
+}