Grid Selected Row Issue

Flow
1

HI

I am using Vaadin 8.1.0

On selecting any row other than first row on grid its selecting properly.
When i select first row its selecting column header, on which i clicked.

In attachement screen i clicked on 0th row and c3 column , but its selected c3 header insted of row.

Here i attched the screen shot of it.

and here is my css code for the same.

.v-grid {

.v-grid-header {
.v-grid-row,
.v-grid-row-has-data {
.v-grid-cell, .frozen, .v-grid-cell-focused {
font-family: sans-serif;

     height: 30px;
     font-size: 12px;
     font-weight: bold;
     line-height: 8px;
     margin-bottom: 10px;
     }
  }
}

.v-grid-body {
.v-grid-row,

  .v-grid-row-has-data {
    .v-grid-cell {
        font-family: sans-serif;
        height: 20px;
        font-size: 12px;
        line-height: 18px;
        border-bottom: none;
      }
      .v-grid-cell-focused:before {
         display: none !important;
       }
     }
  }

}

Regards
Nagaraj RC
40102.png