All php & css at my site. Just wanted to confirm if its correct?

Hi,

Below is the details of total external coding I am using at my site:

A) via Code Snippet Plugin:

i) For WooCommerce Product Sale Badge:

add_filter('woocommerce_sale_flash', 'woocommerce_custom_sale_text', 10, 3);
function woocommerce_custom_sale_text($text, $post, $_product)
{
return '<span class="onsale">40% OFF</span>';
}

B) at Additional CSS: (Some css was given by GP team and some I copied from support topic)

.woocommerce-breadcrumb a{
color: #f7f7f7;
}
.woocommerce-breadcrumb a:hover{
color: light green;
}
.woocommerce-breadcrumb {
color: white !important;
font-weight: 600;
}
h2.woocommerce-loop-category__title mark.count {
color: white;
opacity: 1;
}

/* GeneratePress Site CSS */ .inside-article,
.sidebar .widget,
.comments-area {
border-right: 2px solid rgba(0, 0, 0, 0.07);
border-bottom: 2px solid rgba(0, 0, 0, 0.07);
box-shadow: 0 0 10px rgba(232, 234, 237, 0.5);
}

/* Featured widget */
.sidebar .widget:first-child,
.sidebar .widget:first-child .widget-title{
background-color: #83b0de;
color: #fff;
}

.separate-containers .page-header {
background: transparent;
padding-top: 20px;
padding-bottom: 20px;
}

.page-header h1 {
font-size: 1.5em;
}

.button, .wp-block-button .wp-block-button__link {
padding: 15px 25px;
}

@media (max-width: 768px) {
.post-image img {
max-width: 100%;
}
} /* End GeneratePress Site CSS */

C) at Simple CSS:

/* button lifts on hover */

.button:hover {
-webkit-transform: translateY(-2px);
transform: translateY(-2px);
}
a.button.product_type_simple.add_to_cart_button.ajax_add_to_cart {
border-radius: 8px;
}
.woocommerce ul.products li.product a.add_to_cart_button {
border: 1px solid #fff;
}
.woocommerce ul.products li.product a img {
border-right: 2px solid rgba(0, 0, 0, 0.07);
border-bottom: 2px solid rgba(0, 0, 0, 0.07);
box-shadow: 0 0 10px rgba(232, 234, 237, 0.5) !important;
}
/* Static color */
.select2-container--default .select2-results__option {
background-color: #414a4c;
color: #fff;
}
/* Static color */
.select2-container--default .select2-results__option {
background-color: #414a4c;
color: #fff;
}
/* Selected color */
.select2-container--default .select2-results__option[aria-selected="true"],
.select2-container--default .select2-results__option[data-selected="true"] {
background-color: #b3dc6c !important;
color: #fff !important;
}
/* Hover-focus color */
.select2-container--default .select2-results__option--highlighted[aria-selected="false"],
.select2-container--default .select2-results__option--highlighted[data-selected="false"] {
background-color: ##54cdf1 !important;
color: #fff !important;
}
.slideout-widget.widget_product_search {
width: 100%;
margin: 0;
padding: 20px;
}
.slideout-widget.widget_product_search input {
border-radius: 25px;
}

1. Could you please guide me if any modification/alteration/deletion is required?
2. Is it all pasted at correct locations?

I am just reconfirming it so it won't affect my site's performance.