diff --git a/sass/_containers.scss b/sass/_containers.scss
index ec0580e..2d63958 100644
--- a/sass/_containers.scss
+++ b/sass/_containers.scss
@@ -56,5 +56,13 @@
 			width: 1rem;
 			height: 1rem;
 		}
+
+		&.dark {
+			background-color: rgba(255, 255, 255, 0.05);
+
+			.icon {
+				background-color: rgba(255, 255, 255, 0.5);
+			}
+		}
 	}
 }
diff --git a/templates/partials/copy_button.html b/templates/partials/copy_button.html
index 7229b10..52fd9b5 100644
--- a/templates/partials/copy_button.html
+++ b/templates/partials/copy_button.html
@@ -15,6 +15,9 @@
 				let button = document.createElement("button");
 				let icon = document.createElement("i");
 				let span = document.createElement("span");
+				{%- if config.markdown.highlight_themes_css | length < 1 %}
+					button.classList.add("dark");
+				{%- endif %}
 				icon.classList.add("icon");
 				span.classList.add("hidden");
 				span.innerHTML = "{{ macros_translate::translate(key='copy_code', default='Copy code', language_strings=language_strings) }}";