grid多表头修改表头高度

.x-grid .x-grid-htable th { 
	height:15px !important;
	padding:1px 2px 2px 1px;
 } 
   
  .x-grid .x-grid-htable tr.x-first-row-header th{
  	height:0px !important;
  	padding:0px 0px 0px 0px;
  }