ilyach199012902ilyachu,
<!DOCTYPE html>
<html>
<head>
<title>Untitled</title>
<meta charset="utf-8">
<style type="text/css">
td{
display: flex;
flex-direction: column;
justify-content: flex-end;
}
td:before{
content: attr(data-num);
font-weight: bold;
font-size: 1.2em;
text-align: center;
}
span{
display: table-cell;
border: 1px solid rgba(0, 0, 0, 1);
flex: 1 0 1;
border-radius: 2px;
}
tr{
display: flex;
}
</style>
</head>
<body>
<script>
let table = '<table><tr>';
for (let i = 1; i < 10; i++) {
let td = `<td data-num="${i}">`;
for (let k = i; k < 10; k++) {
td += `<span>${i} * ${k} = ${i * k}</span>`
}
table += td
}
document.body.insertAdjacentHTML('afterbegin', table)
</script>
</body>
</html>