make layout responsive to screen width, reducing body width

static/css/style.css

@@ -46,7 +46,7 @@ s:hover {
 }
 
 #content {
-    width: 75%;
+    width: 95%;
     margin-left: auto;
     margin-right: auto;
 }
@@ -74,6 +74,24 @@ a.anchor {
     }
 }
 
+@media (min-width: 1000px) {
+    #content {
+        width: 75%;
+    }
+}
+
+@media (min-width: 1500px) {
+    #content {
+        width: 50%;
+    }
+
+    #navbar {
+        position: relative;
+        left: 12.5%;
+        width: 75%;
+    }
+}
+
 ._sh {
     max-height: 300px;
     overflow: auto;