Change approach to centering images to avoid a weird element overflow issue

assets/style.css

@@ -32,9 +32,12 @@ main li b {
   padding-right: 2ch
 }
 
+figure {
+  position: relative;
+  margin-block: 10px 0;
+}
+
 img {
-  margin: 10px 0 10px 50%;
-  transform: translateX(-50%);
   max-width: 100%;
 }
 
@@ -60,4 +63,4 @@ footer a {
   a { color: #ccf }
   mark { color: #fcc }
   hr { border-color: #555 }
-}
+}