TD column width value not working with fixed table-layout

Answer 1

suggest such an option

HTML

    
col1
    
col2
    
col3
    
col4
    
col5
    
col6
    
col7
    
col8

CSS

.tableStyle{
table-layout:fixed;
margin: 0 auto; width: 960px;
  background: #ffffd;
}
td:nth-child(1n) {
  width: 20px;
  background: #876342;
}
td:nth-child(3n+1) {
  width: 100px;
}

demo