fix: KaTeX display blocks + prose spacing

- Replace overflow-x: auto with overflow: visible on .katex-display
- Add white-space: normal on .katex-display > .katex
- Add responsive scaling at 640px breakpoint
- Add prose integration margin rules for spacing between prose and math

app/globals.css

@@ -282,9 +282,28 @@ html.dark code[data-theme*=" "] span {
   font-size: 1.1em !important;
 }
 .katex-display {
-  margin: 1.5rem 0;
-  overflow-x: auto;
+  overflow: visible;
+  max-width: 100%;
+  margin: 1.5em 0;
+  text-align: center;
 }
+.katex-display > .katex {
+  display: block;
+  text-align: center;
+  white-space: normal;
+}
+@media (max-width: 640px) {
+  .katex-display > .katex {
+    transform: scale(0.85);
+    transform-origin: center top;
+  }
+  .katex-display {
+    margin: 0.8em 0;
+  }
+}
+.prose p + .katex-display { margin-top: 0.5em; }
+.prose .katex-display + p { margin-bottom: 0.5em; }
+.prose p .katex { vertical-align: middle; }
 .katex .katex-mathml {
   position: absolute;
   clip: rect(1px, 1px, 1px, 1px);