<div class="table">
<div class="table_headline">
<div class="cell_1">When?</div>
<div class="cell_2">What?</div>
<div class="cell_3">Who?</div>
<div class="cell_4">Where?</div><br>
</div>

<div class="row">
<div class="cell_1">Date</div>
<div class="cell_2">Concert</div>
<div class="cell_3">Artist #1 + Artist #2 + Artist #3</div>
<div class="cell_4">Venue</div><br>
</div>
<div class="info">Infos</div>

<div class="row">
<div class="cell_1">Date</div>
<div class="cell_2">Concert</div>
<div class="cell_3">Artist #1 + Artist #2 + Artist #3</div>
<div class="cell_4">Venue</div><br>
</div>
<div class="info">Infos</div>

<div class="row">
<div class="cell_1">Date</div>
<div class="cell_2">Concert</div>
<div class="cell_3">Artist #1 + Artist #2 + Artist #3</div>
<div class="cell_4">Venue</div><br>
</div>
<div class="info">Infos</div>
</div>

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$('.row').on('click', function() {
    $(this).closest('.table').find('.info').slideToggle();
})
})
</script>

$(this).closest('.table').find('.info').slideToggle();

$(this).next().slideToggle();

$('.row').on('click', function() {
    $(this).next('.info').slideToggle();
})