fix: 增加底部padding避免footer遮挡内容

frontend/index.html

@@ -22,7 +22,7 @@
     * { box-sizing:border-box; }
     html, body { height:100%; margin:0; }
     body {
-      padding:0 0 80px;
+      padding:0 0 120px;
       background:radial-gradient(ellipse at top, #0f1624 0%, #0a0e1a 100%);
       color:var(--text);
       font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,PingFang SC,Hiragino Sans GB,Microsoft YaHei,Noto Sans,Arial,sans-serif;