i'm not happy with this but it's better for width

css/post-toc.css

@@ -1,9 +1,8 @@
 #toc {
 	float: right;
 	margin: 1rem 0 1.5rem 1.5rem;
-	/* 23rem is the width of the words 'table of contents' in my header font */
-	/* yes, it's a bit hacky */
-	width: min(calc(100% - 1.5rem), 23rem);
+	width: fit-content;
+	max-width: 55%;
 }
 
 @media (max-width: 850px) {
@@ -12,6 +11,7 @@
 		margin-top: 2rem;
 		margin-left: .5rem;
 		width: calc(100% - .5rem);
+		max-width: unset;
 	}
 }
 
@@ -30,6 +30,7 @@
 	background: var(--color-bg);
 	border-radius: .5rem;
 	cursor: pointer;
+	padding-inline-end: .25rem;
 }
 
 #toc summary:focus-visible {
@@ -53,7 +54,7 @@
 
 /* `tree` style toc */
 #toc nav > ol {
-	margin-left: 1rem;
+	margin-inline: 1rem;
 }
 
 #toc ol {