Index: src/wp-admin/css/customize-controls.css
===================================================================
--- src/wp-admin/css/customize-controls.css	(revision 60000)
+++ src/wp-admin/css/customize-controls.css	(working copy)
@@
 /* Site Icon and Logo controls */
-.customize-control-site_icon .upload-dropzone,
-.customize-control-site_logo .upload-dropzone {
-    border: 2px dashed #ccc;
-    padding: 10px;
-    text-align: center;
-    cursor: pointer;
-}
+.customize-control-site_icon .upload-dropzone,
+.customize-control-site_logo .upload-dropzone {
+    border: 1px solid #ccc; /* Normal button-like border */
+    padding: 6px 12px;
+    background-color: #f6f7f7;
+    text-align: center;
+    cursor: pointer;
+    border-radius: 3px;
+}
+
+.customize-control-site_icon .upload-dropzone:hover,
+.customize-control-site_logo .upload-dropzone:hover {
+    background-color: #f0f0f0;
+}