Use the following code to make tables with black headers.
<style>
table, th, td { border: 0.5px solid; }
td { padding: 4px; }
th { color: white; background-color: #000; padding: 6px; }
</style>
| ID | Letter | Call Sign |
|---|---|---|
| 0001 | A | Alpha |
| 0002 | B | Bravo |
| 0003 | C | Charlie |
<table class="w3-medium"> <tr><th><strong>ID</strong></th><th><strong>Letter</strong></th> <th><strong>Call Sign</strong></th></tr> <tr><td>0001</td><td>A</td><td>Charlie</td></tr> <tr><td>0002</td><td>B</td><td>Bravo</td></tr> <tr><td>0003</td><td>C</td><td>Charlie</td></tr> </table>