一些微小的贡献

components/Timetable.tsx

@@ -115,7 +115,7 @@ const Timetable = ({
     tds.length = 0;
 
     const table = target.children[0];
-    table.setAttribute("border", "1");
+    table.setAttribute("border", "0");
 
     // mark cell
     const conflictsTmp: ConflictsTmp = {};
@@ -266,6 +266,7 @@ const Timetable = ({
     <>
       <h2 style={{ textAlign: "center" }}>Login as {user}</h2>
       <div
+        align="center"
         ref={ref}
         contentEditable={editable}
         style={{