feat(blog): responsive tweaks for taxonomy cloud and series box

Add @media (max-width: 768px) rules so the home taxonomy chip cloud
goes full-width with smaller chips on narrow screens (plus a 340px
step-down), and so the series box's prev/next nav stacks vertically
instead of squeezing two links side by side.

Author: lzm

assets/css/extended/home-taxonomies.css

@@ -85,4 +85,26 @@
     font-size: 0.7rem;
     font-weight: 600;
     line-height: 1;
-}
+}
+/* Mobile: single-column, tighter chips so nothing overflows on 340px. */
+@media screen and (max-width: 768px) {
+    .home-taxonomies {
+        max-width: 100%;
+        padding: 1.25rem 1rem 0;
+        margin-top: 1.25rem;
+        gap: 1rem;
+    }
+    .home-taxonomy-chip {
+        font-size: 0.8rem;
+        padding: 0.25rem 0.6rem;
+    }
+    .home-taxonomy-count {
+        min-width: 1.3em;
+        height: 1.3em;
+    }
+}
+@media screen and (max-width: 340px) {
+    .home-taxonomy-chip {
+        font-size: 0.75rem;
+    }
+}

assets/css/extended/series-box.css

@@ -182,4 +182,20 @@
     color: var(--secondary);
     font-size: 1rem;
     line-height: 1;
-}
+}
+/* Mobile: stack the prev/next nav vertically so long titles stay readable. */
+@media screen and (max-width: 768px) {
+    .series-box {
+        padding: 0.75rem 1rem;
+    }
+    .series-box-list li {
+        padding: 0.4rem 0;
+    }
+    .series-box-nav {
+        flex-direction: column;
+        gap: 0.5rem;
+    }
+    .series-box-nav-link {
+        max-width: 100%;
+    }
+}