Remove padding above and below related items

/* -- code to reduce padding above and below related items -- */
.template-product .page-margin {
    padding-top: 0px;
}
.template-product .product-section>.wrapper:last-of-type {
    padding-bottom: 0px;
}
.template-product .main-content {
    margin-bottom: -30px;
}
/* - end - */

If you find the space is too tight above Related items, change the first one from 0px to 10px or 30px, adjust accordingly.

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