ENGCOM-4303: iPhone5-device-newsletter-subscription-#20167 #20370

Author: sidolov

app/design/frontend/Magento/luma/Magento_Newsletter/web/css/source/_module.less

@@ -81,3 +81,24 @@
         width: 34%;
     }
 }
+
+//
+//  Mobile
+//  _____________________________________________
+
+.media-width(@extremum, @break) when (@extremum = 'max') and (@break = @screen__m) {
+    .block {
+        &.newsletter {
+            input {
+                font-size: 12px;
+                padding-left: 30px;
+            }
+
+            .field {
+                .control:before {
+                    font-size: 13px;
+                }
+            }
+        }
+    }
+}