Local storage - store boolean

<script>
console.log('Start');

var cond = localStorage.getItem('cond');
if (cond === null) {
    console.log('was null setting to false');
    cond = false;
} else {
    cond = JSON.parse(cond)
}

console.log(cond);
cond = ! cond;
console.log(cond);
localStorage.setItem("cond", cond);

console.log('End');
</script>