Melonbooks add-to-cart button colors by AquaWolfGuy

/* ==UserStyle==
@name         Melonbooks add-to-cart button colors
@description  Colors add-to-cart buttons cyan (pre-order) or orange-yellow (in stock) in the favorites list, and brown (downloadable) in product listings.
@license      CC-BY-NC-SA-4.0
@namespace    AquaWolfGuy
@author       AquaWolfGuy
@version      1
@preprocessor default
@var color in-stock-color "In-stock color" #ffc541
@var color pre-order-color "Pre-order color" #26bfdd
@var color dl-color "Downloadable color" #CCAA9B
==/UserStyle== */

@-moz-document url-prefix("https://www.melonbooks.co.jp/mypage/favorite.php") {
	/* Colored add-to-cart buttons in wishlist according to in-stock or reservations. */

	/* In stock */
	.my-page .item-list .btns p.favorite a.cart_in_button[title="今すぐ購入"] {
		background-color: var(--in-stock-color, #ffc541);
		border-color: transparent;
	}

	/* Pre-order */
	.my-page .item-list .btns p.favorite a.cart_in_button[title="今すぐ予約"] {
		background-color: var(--pre-order-color, #26bfdd);
		border-color: transparent;
	}

	/* Icon */
	.my-page .item-list .btns p.favorite a.cart_in_button[title="今すぐ購入"]::before,
	.my-page .item-list .btns p.favorite a.cart_in_button[title="今すぐ予約"]::before {
		color: #fff;
		border-color: #fff;
	}

	/* Text */
	.my-page .item-list .btns p.favorite a.cart_in_button[title="今すぐ購入"] > span,
	.my-page .item-list .btns p.favorite a.cart_in_button[title="今すぐ予約"] > span {
		color: #fff;
	}
}

@-moz-document domain("melonbooks.co.jp") {
	/* Add-to-cart buttons for downloadable/electronic products. */

	.item-list .search-item-detail-btn-list a.dl_to_wish,
	.search-item-cover .search-item-detail-btn-list a.dl_to_wish,
	.btn-cart .read_button.oneclick_button,
	.btn-cart .read_button.dl_cart_button {
		background-color: var(--dl-color, #CCAA9B) !important;
	}
}