fix absolute assets links

nginx/covid_website/assets/css/style.css

@@ -293,10 +293,10 @@ hr {
             flex: 1 1 100%; } }
 
 .page-home .hero-container {
-  background-image: url("/assets/img/hero/mapswipe_grid.png"); }
+  background-image: url("../img/hero/mapswipe_grid.png"); }
 
 .page-about .hero-container {
-  background-image: url("/assets/img/hero/field_mapping.jpg"); }
+  background-image: url("../img/hero/field_mapping.jpg"); }
 
 .page-about .steps {
   background-image: -webkit-gradient(linear, left top, right top, from(#e6efc6), to(#f7e8ac));
@@ -423,13 +423,13 @@ hr {
       margin: 20px; }
 
 .page-data .hero-container {
-  background-image: url("/assets/img/hero/msf_mapping.jpg"); }
+  background-image: url("../img/hero/msf_mapping.jpg"); }
 
 .page-data .one-half .link {
   margin-top: 10px; }
 
 .page-involved .hero-container {
-  background-image: url("/assets/img/hero/mapswipe_mapathon.jpg"); }
+  background-image: url("../img/hero/mapswipe_mapathon.jpg"); }
 
 .prefooter .container,
 footer .container {