update

resources/views/filter/container.blade.php

@@ -1,4 +1,4 @@
-<div class="card p-2 {{ $expand ? '' : 'd-none' }} {{$containerClass}}" style="{{$border}};margin-top: 10px;margin-bottom: 8px">
+<div class="card p-2 {{ $expand ? '' : 'd-none' }} {{$containerClass}}" style="{{$border}};margin-top: 10px;margin-bottom: 8px;box-shadow: 0 2px 3px 0 rgba(0, 0, 0, 0.04);border-radius: .3rem">
     <div class="card-body" style="{!! $style !!}"  id="{{ $filterID }}">
         <form action="{!! $action !!}" class="form-horizontal" pjax-container method="get">
             <div class="row">

src/Grid/Tools.php

@@ -9,10 +9,10 @@ use Dcat\Admin\Grid\Tools\BatchActions;
 use Dcat\Admin\Grid\Tools\FilterButton;
 use Dcat\Admin\Grid\Tools\RefreshButton;
 use Dcat\Admin\Support\Helper;
-use Illuminate\Support\Str;
 use Illuminate\Contracts\Support\Htmlable;
 use Illuminate\Contracts\Support\Renderable;
 use Illuminate\Support\Collection;
+use Illuminate\Support\Str;
 
 class Tools implements Renderable
 {