I need help adjusting the white space gap between my First Column and Second Column in a square grid. They currently appear too far apart, and I would like to specify exact measurements for this gap while keeping the pictures in a square shape. Additionally, being able to set row divider measurements would be helpful as well. Please refer to the green arrow in the picture link below for visual clarity.
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<title>JS Bin</title>
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<div class="container">
<div class="row">
<div class="col-6 justify-content-center d-flex"><img class="img-thumbnail w-100" src="https://www.woodlandtrust.org.uk/media/100078482/Sycamore01.jpg?cb=-11897985&preset=gallery-tab-main-image"></div>
<div class="col-6 justify-content-center d-flex"><img class="img-thumbnail w-100" src="https://statesymbolsusa.org/sites/statesymbolsusa.org/files/styles/symbol_thumbnail__medium/public/primary-images/Applesfreshpicked.jpg?itok=YmYkBfY7"></div>
<div class="col-6 justify-content-center d-flex"><img class="img-thumbnail w-100" src="https://openbookphilly.com/wp-content/uploads/2016/11/bookstack.png"></div>
<div class="col-6 justify-content-center d-flex"><img class="img-thumbnail w-100" src="https://media.wired.com/photos/5b86fce8900cb57bbfd1e7ee/master/w_582,c_limit/Jaguar_I-PACE_S_Indus-Silver_065.jpgColumn"></div>
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For more information on creating an equal size square grid picture system using HTML, please visit: HTML Create an Equal Size Square Grid Picture System