fix: footer sticky — body flex-column + main-content flex:1

style.css

@@ -1,6 +1,6 @@
 /*
 Theme Name: 空笺未寄
-Version: 0.14.1
+Version: 0.14.2
 Requires at least: 6.0
 Requires PHP: 7.4
 License: MIT
@@ -34,8 +34,8 @@ Text Domain: kj-weji
             min-height: 100vh;
             line-height: 1.8;
             display: flex;
-            justify-content: center;
-            padding: calc(var(--topbar-height) + 24px) 20px 40px;
+            flex-direction: column;
+            padding: 0;
         }
         .platform {
             width: 100%;
@@ -82,7 +82,7 @@ Text Domain: kj-weji
             content:''; position:absolute; bottom:-4px; left:50%; transform:translateX(-50%);
             width:4px; height:4px; background:var(--cinnabar); border-radius:50%;
         }
-        .main-content { padding:40px; min-height:500px; }
+        .main-content { flex: 1; padding: calc(var(--topbar-height) + 24px) 20px 40px; }
 
         /* 首页 */
         .hero { text-align:center; padding:48px 20px 32px; }