feat: improve app ui and project metadata

apps/web/tailwind.config.ts

@@ -2,7 +2,11 @@ import type { Config } from "tailwindcss";
 
 // 纸感·文学温暖主题（UX_SPEC §2）。颜色经 CSS 变量落地，便于后续夜读模式切换。
 const config: Config = {
-  content: ["./app/**/*.{ts,tsx}", "./components/**/*.{ts,tsx}"],
+  content: [
+    "./app/**/*.{ts,tsx}",
+    "./components/**/*.{ts,tsx}",
+    "./lib/**/*.{ts,tsx}",
+  ],
   theme: {
     extend: {
       colors: {
@@ -23,7 +27,7 @@ const config: Config = {
         mono: ['"JetBrains Mono"', "ui-monospace"],
       },
       borderRadius: { DEFAULT: "6px" },
-      boxShadow: { paper: "0 1px 3px #2B26200F" },
+      boxShadow: { paper: "0 1px 3px var(--shadow-paper)" },
       maxWidth: { prose: "720px" },
     },
   },