<!DOCTYPE html>
<html>
<body>
<script>
'use strict';
var currentTime = new Date();
var openingHour = currentTime.setHours(11, 0)
var closingHour = currentTime.setHours(23, 0)
\
if (+currentTime > openingHour && +currentTime < closingHour) {
console.log('открыто');
}
</script>
</body>
</html>