I am struggling displaying a table in HTML with a rather complicated structure and would like some help in trying to figure out what the problem might be. My goal is to print out the following table in HTML:
Desired layout

Actual layout when shown using HTML:
table td {
border: 1px solid black;
}
table {
width: 100%;
}
<table>
<tr>
<td rowspan="3" colspan="1">
1
</td>
<td rowspan="3" colspan="2">
2
</td>
<td rowspan="1" colspan="1">
3
</td>
<td rowspan="1" colspan="1">
4
</td>
</tr>
<tr>
<td rowspan="2" colspan="2">
5
</td>
</tr>
<tr>
<td rowspan="1" colspan="1">
6
</td>
<td rowspan="1" colspan="1">
7
</td>
<td rowspan="1" colspan="1">
8
</td>
<td rowspan="2" colspan="1">
9
</td>
<td rowspan="1" colspan="1">
10
</td>
</tr>
<tr>
<td rowspan="1" colspan="1">
11
</td>
<td rowspan="1" colspan="1">
12
</td>
<td rowspan="1" colspan="1">
13
</td>
<td rowspan="1" colspan="1">
14
</td>
</tr>
<tr>
<td rowspan="1" colspan="1">
15
</td>
<td rowspan="1" colspan="1">
16
</td>
<td rowspan="1" colspan="1">
17
</td>
<td rowspan="1" colspan="1">
18
</td>
<td rowspan="1" colspan="1">
19
</td>
</tr>
</table>
You can see the result here: https://codepen.io/lexokag/pen/OJWyojq
Can you advise where do I have a mistake in my colspans/rowspans?