diff --git a/make-pdf/src/print-css.ts b/make-pdf/src/print-css.ts
index 2366f42b99..e0b4ec7edf 100644
--- a/make-pdf/src/print-css.ts
+++ b/make-pdf/src/print-css.ts
@@ -35,8 +35,8 @@
 // Metric-compatible sans stack: Helvetica (macOS), Liberation Sans (Linux,
 // ships via fonts-liberation), Arial (Windows). Shared by every text surface.
 const SANS_STACK = `Helvetica, "Liberation Sans", Arial`;
-// CJK fallback families, appended to the body stack only.
-const CJK_STACK = `"Hiragino Kaku Gothic ProN", "Noto Sans CJK JP", "Microsoft YaHei"`;
+// CJK fallback families (Simplified-Chinese first), appended to the body stack only.
+const CJK_STACK = `"PingFang SC", "Heiti SC", "Noto Sans CJK SC", "Source Han Sans SC", "Microsoft YaHei", "Hiragino Kaku Gothic ProN", "Noto Sans CJK JP"`;
 // Color-emoji families: Apple (macOS), Segoe (Windows), Noto (Linux).
 const EMOJI_FAMILIES = `"Apple Color Emoji", "Segoe UI Emoji", "Noto Color Emoji"`;
 
diff --git a/make-pdf/src/smartypants.ts b/make-pdf/src/smartypants.ts
index 2dfe097e09..5f794a2aa7 100644
--- a/make-pdf/src/smartypants.ts
+++ b/make-pdf/src/smartypants.ts
@@ -20,7 +20,7 @@
 
 const CODE_ZONE_RE = /<(pre|code|script|style)\b[^>]*>[\s\S]*?<\/\1>/gi;
 const TAG_RE = /<[^>]+>/g;
-const URL_RE = /\bhttps?:\/\/\S+/g;
+const URL_RE = /\bhttps?:\/\/[^\s\u0000]+/g;
 
 /**
  * Apply smartypants to an HTML string. Zones that should not be touched:
@@ -44,7 +44,7 @@ export function smartypants(html: string): string {
     });
   };
 
-  let s = html;
+  let s = html.replace(/\u0000/g, "");  // drop stray input NUL (can't forge a placeholder)
   s = carve(s, CODE_ZONE_RE);
   s = carve(s, TAG_RE);
   s = carve(s, URL_RE);
@@ -89,11 +89,11 @@ function transformText(text: string): string {
 
   // Double quotes: open if preceded by whitespace/bol, close if preceded
   // by word char or punctuation.
-  s = s.replace(/(^|[\s\(\[\{\-])"/g, "$1\u201c");     // opening "
+  s = s.replace(/(^|[\s\(\[\{\-：（【「『〈《])"/g, "$1\u201c");     // opening "
   s = s.replace(/"/g, "\u201d");                         // remaining " are closing
 
   // Single quotes (after apostrophe pass):
-  s = s.replace(/(^|[\s\(\[\{\-])'/g, "$1\u2018");      // opening '
+  s = s.replace(/(^|[\s\(\[\{\-：（【「『〈《])'/g, "$1\u2018");      // opening '
   s = s.replace(/'/g, "\u2019");                         // remaining ' are closing
 
   return s;