modify footer

-<p>opensource project 2018103999 박은수 201700000 오수빈</p>
\ No newline at end of file
+<p>2021-1 SW Opensource project</p>
+<p>2018103999 박은수 201700000 오수빈</p>
\ No newline at end of file

@@ -13,15 +13,24 @@
   <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/js/bootstrap.min.js"></script>
 
   <style>
+    html {
+      min-height: 100%;
+      position: relative;
+    }
+
+    body {
+      height: 100%;
+    }
+
     .content {
       display: flex;
       flex-direction: row;
+      height: 500px;
     }
 
     .nav {
       flex: 1;
       background-color: black;
-
     }
 
     .jumbotron {
@@ -30,9 +39,12 @@
       background-color: white;
     }
 
-    #footer {
+    footer {
+      position: absolute;
+      bottom: 0;
+      width: 100%;
       text-align: center;
-      background-color: gray;
+      background-color: black;
       color: white;
       font-weight: lighter;
     }