Search filters changes

Better search filters view on mobile.

searx/static/themes/simple/src/less/search.less

@@ -164,6 +164,9 @@
   .ltr-margin-right(0);
   margin-bottom: 0;
   .ltr-margin-left(@results-offset + 0.6rem);
+  display: flex;
+  overflow-x: auto;
+  overscroll-behavior-inline: contain;
 
   select {
     background-color: inherit;