Answers for "space background"

tr background color

<table>
  <tr bgcolor="#ddd">
    <td>First column</td>
    <td>Second column</td>
    <td>Third column</td>
  </tr>
  <tr bgcolor="#eee">
    <td>First column</td>
    <td>Second column</td>
    <td>Third column</td>
  </tr>
  <tr bgcolor="#ddd">
    <td>First column</td>
    <td>Second column</td>
    <td>Third column</td>
  </tr>
</table>

html watermark background

#watermark {
   position:fixed;
   bottom:5px;
   right:5px;
   opacity:0.5;
   z-index:99;
   color:white;
   user-select: none;
}