优化 table 在末行展开单元格后，出现的固定列水平未对其的问题

src/css/layui.css

@@ -872,11 +872,11 @@ hr.layui-border-black{border-width: 0 0 1px;}
 .layui-form-checkbox:hover > div{background-color: #c2c2c2;}
 .layui-form-checkbox > i{position: absolute; right: 0; top: 0; width: 30px; height: 100%; border: 1px solid #d2d2d2; border-left: none; border-radius: 0 2px 2px 0; color: #fff; color: rgba(255,255,255,0); font-size: 20px; text-align: center; box-sizing: border-box;}
 .layui-form-checkbox:hover > i{border-color: #c2c2c2; color: #c2c2c2;}
-.layui-form-checked, 
+.layui-form-checked,
 .layui-form-checked:hover{border-color: #16b777;}
-.layui-form-checked > div, 
+.layui-form-checked > div,
 .layui-form-checked:hover > div{background-color: #16b777;}
-.layui-form-checked > i, 
+.layui-form-checked > i,
 .layui-form-checked:hover > i{color: #16b777;}
 .layui-form-item .layui-form-checkbox{margin-top: 4px;}
 .layui-form-checkbox.layui-checkbox-disabled > div{background-color: #eee !important;}
@@ -1176,6 +1176,7 @@ select.layui-table-edit{padding: 0 0 0 10px; border-color: #d2d2d2;}
 .layui-table-cell-c{position: absolute; bottom: -10px; right: 50%; margin-right: -9px; width: 20px; height: 20px; line-height: 18px; cursor: pointer; text-align: center; background-color: #fff; border: 1px solid #eee; border-radius: 50%; z-index: 1000; transition: 0.3s all; font-size: 14px;}
 .layui-table-cell-c:hover{border-color: #16b777;}
 .layui-table-expanded td:hover .layui-table-cell{overflow: auto;}
+.layui-table-main > .layui-table > tbody > tr:last-child > td > .layui-table-cell-c{bottom: 0;}
 
 /* 单元格 TIPS 展开风格  */
 body .layui-table-tips .layui-layer-content{background: none; padding: 0; box-shadow: 0 1px 6px rgba(0,0,0,.12);}