While it affects nothing, I thought I would mention it. Less code to maintain is always better. Around line 884 of _variables.scss in the free folder has duplicated code. Here is what is duplicated:

// Breadcrumbs

$breadcrumb-item-color: rgba(0, 0, 0, 0.55);
$breadcrumb-item-transition: color 0.15s ease-in-out;
$breadcrumb-item-hover-color: rgba(0, 0, 0, 0.7);
$breadcrumb-item-before-color: $breadcrumb-item-color;

// Images

$image-hover-overlay-transition: all 0.3s ease-in-out;

$image-hover-zoom-transition: all 0.3s linear;
$image-hover-zoom-transform: scale(1.1);

$image-hover-shadow-transition: $image-hover-overlay-transition;
$image-hover-shadow-box-shadow: 0 8px 17px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);

// Scrollspy

$scrollspy-menu-sidebar-font-size: 0.8rem;
$scrollspy-menu-sidebar-color: #262626;
$scrollspy-menu-sidebar-line-height: 1.1rem;
$scrollspy-menu-sidebar-padding-x: 5px;
$scrollspy-menu-sidebar-font-weight: 400;
$scrollspy-menu-sidebar-transition: all 0.2s ease-in-out;
$scrollspy-menu-sidebar-margin-y: 3px;

$scrollspy-menu-sidebar-active-color: $primary;
$scrollspy-menu-sidebar-active-font-weight: 600;
$scrollspy-menu-sidebar-active-border-width: 0.125rem;
$scrollspy-menu-sidebar-active-border-color: $primary;