LocalCSS

See Cookbook:LocalCSS.

 PmWiki.Tables-Talk

/* thick border around Everest (3rd row, 3rd column) */
table.mytable tr:nth-child(3) td:nth-child(3) {
  border: 3px solid green;
  background-color: yellow;
}

/* thin dashed border around Argentina (6th row, 4th column) */
table.mytable tr:nth-child(6) td:nth-child(4) {
  border: 2px dashed red;
}

table.myothertable {
  border-collapse: collapse;
}
table.myothertable th {
  border: 4px solid blue;
}

table.myadvancedtable {
  border-collapse: collapse;
  width: 100%;
}
table.myadvancedtable td.thickborder {
  border: 4px solid black;
  background-color: #00b0f0;
}
table.myadvancedtable td.thinborder {
  border: 1px solid red;
}