use flat backgrounds

assets/css/index.css

@@ -3,14 +3,12 @@
 }
 
 body {
-    background:#f0f0f3 url(../images/noise_blue3.png);
+    background: #d6dcdc;
 }
 
 .header {
     text-align: center;
-    background: #393f42;
-    /* background: linear-gradient( #464d51 , #393f42 ); */
-    background: #393f42 url(../images/background-grayblue.png);
+    background: #66696d;
     /* background-size: cover; */
     position: relative;
     overflow: visible;
@@ -80,7 +78,7 @@ body {
 .header-subnav li a.is-active {
     /* background: #ffffff; */
     color: #393f42;
-    background-image:url(../images/noise_blue3.png);
+    background: #d6dcdc;
 }
 
 .header-subnav li a:not(.is-active):hover {