Draw tree line as inline SVG and declare dark color scheme

styles.css

@@ -1,4 +1,5 @@
 :root {
+  color-scheme: dark;
   --spruce: #0f1512;
   --spruce-2: #161f1a;
   --spruce-3: #1f2a23;
@@ -35,14 +36,14 @@ body {
   overflow: hidden;
 }
 
-.hero::after {
-  content: "";
+.treeline {
   position: absolute;
   left: 0;
-  right: 0;
   bottom: -1px;
+  width: 100%;
   height: 90px;
-  background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 120 60' preserveAspectRatio='none'%3E%3Cpath fill='%230f1512' d='M0 60 L0 44 L8 30 L5 30 L12 16 L9 16 L16 2 L23 16 L20 16 L27 30 L24 30 L32 44 L32 60 Z M30 60 L38 40 L35 40 L42 26 L39 26 L46 14 L53 26 L50 26 L57 40 L54 40 L62 60 Z M58 60 L66 36 L63 36 L71 20 L68 20 L76 6 L84 20 L81 20 L89 36 L86 36 L94 60 Z M90 60 L97 44 L94 44 L101 30 L98 30 L105 20 L112 30 L109 30 L116 44 L113 44 L120 60 Z'/%3E%3C/svg%3E") repeat-x bottom / 120px 90px;
+  color: var(--spruce);
+  display: block;
 }
 
 .hero-inner {