How can I do this with a PHP loop?

[Minizerg]

Here is the rewritten content in English with preserved original meaning and optimized for SEO compatibility:

"I need help with creating a design where a square will appear in the middle, opposite the other elements. If you can assist, I would appreciate it. This design can be achieved with the following code:
$isim="**********";
$length=strlen($isim);
for ($i=0; $i<$length; $i++) {
for ($j=0; $j<$length; $j++) {
echo "$isim[$j]";
}
echo "";
}
for ($i=$length-1; $i>=0; $i--) {
for ($j=0; $j<$length; $j++) {
echo "$isim[$j]";
}
echo "";
}