update style

app.css

@@ -149,29 +149,38 @@
   }
 }
 
+.probelm-input-container {
+  border: 1px solid rgba(0, 0, 0, 0.15);
+}
+
 .problem-input-markdown {
-  padding-top: 18px;
+  padding-top: 24px 12px 12px 12px;
   border: 1px solid rgba(0, 0, 0, 0.15);
   border-radius: 10px;
   position: relative;
   max-height: 380px;
   overflow-y: auto;
+  border-width: 1px;
+  border: 1px solid rgba(0, 0, 0, 0.15);
 }
 
 .problem-input-markdown::before {
   content: "Problem rendered";
   border: 1px solid rgba(0, 0, 0, 0.15);
-  border-radius: 0 10px 0 0px;
+  border-radius: 10px 0px 10px 0px;
   position: absolute;
   left: 0;
   top: 0;
   border-right: 1px solid rgba(0, 0, 0, 0.15);
   border-bottom: 1px solid rgba(0, 0, 0, 0.15);
+  border-left: 0;
+  border-bottom: 0;
   padding: 4px 8px;
 }
 
 .problem-input-markdown .problem-input-markdown {
   border: none;
+  padding: 0;
 }
 
 .problem-input-markdown .problem-input-markdown::before {