fix: adjust heading font sizes in markdown content to be smaller than page title

Author: kael-odin

src/styles/common.css

@@ -467,47 +467,47 @@
 
 /* Heading Levels */
 .sl-markdown-content h1 {
-    font-size: 72px;
+    font-size: 2rem;
     font-weight: 700;
-    line-height: 1.0;
-    letter-spacing: -0.025em;
+    line-height: 1.2;
+    letter-spacing: -0.02em;
     color: #111827;
 }
 
 .sl-markdown-content h2 {
-    font-size: 48px;
+    font-size: calc(1.5rem + 2px);
     font-weight: 700;
-    line-height: 1.1;
-    letter-spacing: -0.02em;
+    line-height: 1.3;
+    letter-spacing: -0.015em;
     color: #111827;
 }
 
 .sl-markdown-content h3 {
-    font-size: 36px;
+    font-size: calc(1.25rem + 2px);
     font-weight: 700;
-    line-height: 1.15;
-    letter-spacing: -0.015em;
+    line-height: 1.4;
+    letter-spacing: -0.01em;
     color: #111827;
 }
 
 .sl-markdown-content h4 {
-    font-size: 24px;
+    font-size: calc(1.125rem + 2px);
     font-weight: 700;
-    line-height: 1.3;
+    line-height: 1.5;
     color: #111827;
 }
 
 .sl-markdown-content h5 {
-    font-size: 20px;
+    font-size: calc(1rem + 2px);
     font-weight: 700;
-    line-height: 1.4;
+    line-height: 1.5;
     color: #111827;
 }
 
 .sl-markdown-content h6 {
-    font-size: 18px;
+    font-size: calc(0.9375rem + 2px);
     font-weight: 600;
-    line-height: 1.4;
+    line-height: 1.5;
     color: #111827;
 }