[FIX] web: fixed css of hidden input file: a hidden element could interfere with other elements

in the dom, leading to some fields not being accessible.

addons/web/static/src/css/base.css

@@ -8,6 +8,7 @@
   font-weight: normal;
   font-style: normal;
 }
+
 @font-face {
   font-family: "EntypoRegular";
   src: url("/web/static/src/font/entypo-webfont.eot") format("eot");
@@ -2217,7 +2218,8 @@
   line-height: 0;
   font-size: 12px;
   position: absolute;
-  top: 1px;
+  top: -30px;
+  width: 100%;
   left: 0;
   right: 0;
   opacity: 0;
@@ -2996,6 +2998,7 @@
     top: 0px;
   }
 }
+
 .kitten-mode-activated {
   background-size: cover;
   background-attachment: fixed;

addons/web/static/src/css/base.sass

@@ -1826,7 +1826,8 @@ $sheet-padding: 16px
             line-height: 0
             font-size: 12px
             position: absolute
-            top: 1px
+            top: -30px
+            width: 100%
             left: 0
             right: 0
             opacity: 0