major cleanup

webapp/src/assets/main.css

@@ -1,17 +1,18 @@
 a {
   font-weight: bold;
-  color: rgb(18, 151, 195);
+  color: var(--df-blue);
   text-decoration: none;
 }
 
-a:hover {
+/* underline only simple <a> elements */
+a:not([class]):hover {
   text-decoration: underline;
 }
 
 :root {
   --df-background-color: white;
   --df-text-color: #ccc;
-  --df-page-background-color: #f5f5f5;
+  --df-blue: rgb(18, 151, 195);
 }
 
 .leaflet-popup-content-wrapper, .leaflet-popup-tip, .leaflet-bar a {

webapp/src/assets/typography.css

@@ -0,0 +1,26 @@
+/* Typography rules */
+
+body {
+  line-height: 1.6;
+  margin: 0;
+  padding: 0;
+}
+
+h1, h2, h3, h4, h5, h6 {
+  margin-top: 1.5em;
+  margin-bottom: 0.5em;
+  font-weight: bold;
+}
+
+p {
+  margin: 0.5em 0;
+}
+
+ul, ol {
+  margin: 1em 0;
+  padding-left: 1.5em;
+}
+
+ul li, ol li {
+  margin: 0.5em 0;
+}