style(about): 方案 A 复核润色（名片留白 + 链接 hover 箭头）

验证: pnpm astro build exit 0；dist/about/index.html 含 .about-id 包裹

Spec: none (已上线方案的复核润色)

Co-authored-by: GLM-5.3

src/components/pages/AboutPage.astro

@@ -31,7 +31,11 @@ const typo = await pageTypography('siteAbout', 'about');
   <div class={typo.className || undefined} style={typo.style || undefined}>
   {docHtml ? (
     <>
-      {showIdCard && <IdCard />}
+      {showIdCard && (
+        <div class="about-id">
+          <IdCard />
+        </div>
+      )}
       <article class="about-doc rich" set:html={docHtml} />
     </>
   ) : blocks.length > 0 ? (
@@ -178,4 +182,9 @@ const typo = await pageTypography('siteAbout', 'about');
     margin: var(--space-6) 0 var(--space-3);
   }
   .about-doc :global(p) { line-height: 1.85; }
+  .about-id { margin-bottom: var(--space-6); }
+  .about-doc :global(li a) { transition: color var(--dur) var(--ease); }
+  .about-doc :global(li a)::after { content: ' ↗'; opacity: 0; transition: opacity var(--dur) var(--ease); }
+  .about-doc :global(li a:hover)::after { opacity: 0.7; }
+  .about-doc :global(li a:hover) { color: var(--accent); }
 </style>