修正

style.css

@@ -1896,6 +1896,12 @@ body #btn-a #mobile-btn {
 
 #information-mobile #mobile-form #form-card .contact-form2 #profession {
   height: 50px;
+  background: url(./img/icondown.webp) 95% 50% no-repeat scroll transparent;
+  background-size: 10px 10px;
+  background-color: #fff;
+  -webkit-appearance: none;
+     -moz-appearance: none;
+          appearance: none;
 }
 
 #information-mobile #mobile-form #form-card .contact-form2 .btn {

style.scss

@@ -1277,6 +1277,10 @@ body {
 
                 #profession {
                     height: 50px;
+                    background: url(./img/icondown.webp) 95% 50% no-repeat scroll transparent;
+                    background-size: 10px 10px;
+                    background-color: #fff;
+                    appearance: none;
                 
                 }
                 .btn {