chore: enhance timeline

Author: openscript

src/components/Timeline.astro

@@ -33,10 +33,14 @@
     transform: translateX(-50%);
     background: linear-gradient(
       to bottom,
-      var(--color-primary) 0.4rem,
+      var(--color-primary) 0.2rem,
+      transparent 0.2rem,
       transparent 0.4rem,
-      transparent 0.55rem,
-      var(--color-primary) 0.55rem
+      var(--color-primary) 0.4rem,
+      var(--color-primary) 0.6rem,
+      transparent 0.6rem,
+      transparent 0.8rem,
+      var(--color-primary) 0.8rem
     );
     z-index: 3; /* above potential dividers */
   }