Custom mask doesn’t work

I used the script to create phone mask for the input field type=”tel” and it worked correctly.

<script type="text/javascript">
jQuery(document).ready(function($){
  $("input[type='tel']").addClass('phone_us');
});
</script>

But I need a mask for Russian number +7 (000) 000-00-00, so I tried to modify the script this way:

<script type="text/javascript">
jQuery(document).ready(function($){
  $("input[type='tel']").mask('+7 (000) 000-00-00');
});
</script>

It didn’t work. When I clicked on the input field there was text “+7 (000) 000-00-00” and it was uneditable, so I couldn’t write there anything using keyboard. Can you help me, where is a mistake?

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