fix: footer sticky — html/platform/site 全链路 height:100%

style.css

@@ -1,6 +1,6 @@
 /*
 Theme Name: 空笺未寄
-Version: 0.14.5
+Version: 0.14.6
 Requires at least: 6.0
 Requires PHP: 7.4
 License: MIT
@@ -24,6 +24,7 @@ Text Domain: kj-weji
             --topbar-height: 64px;
         }
         * { margin:0; padding:0; box-sizing:border-box; }
+        html, .platform { height: 100%; }
         body {
             font-family: "Source Han Serif SC", "STSong", "Songti SC", "PingFang SC", "Microsoft YaHei", Georgia, serif;
             background-color: #f0ece3;
@@ -258,6 +259,7 @@ Text Domain: kj-weji
 /* WP wrapper — ensure full width in body flex container */
 .site {
   width: 100%;
+  height: 100%;
   display: flex;
   justify-content: center;
 }