to connect your PHP with phpMyAdmin,
$connection = mysqli_connect('localhost','usersname','password','query');
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QUERY
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CLASS
<div class="container> to create container
<div class="col"> to create column
<div class="row mt-3"> to create row with number row are 3
<
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CSS
https://getbootstrap.com/docs/4.0/utilities/colors/
bg-dark = black color