If the option is selected, fills in the input

How, using only HTML and CSS, to make it so that when I select an option in , my input is filled in?
Here is my code

<select class="cod_art" name="cod_art" id="cod_art_01">
<option value="Default">Default1</option>
<option value="Default">Default2</option>
</select>
<input type="text" id="descrizione_01" name="descrizione" readonly>

So, if I select Default1 option, in input will fill a text, for example “example1”.
How can I do it in JS?