Brighter obsidian for the soul core thrones, so their stone shows

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/render3d.rs

@@ -2764,7 +2764,7 @@ fn ring(c: Vec3, r: f32, color: Color) {
 
 // the obsidian throne of a soul core (centre c on the floor)
 fn draw_throne(c: Vec3, t: f32) {
-    let obs = |k: u8| Color::from_rgba(28 + k, 14 + k / 2, 20 + k / 2, 255);
+    let obs = |k: u8| Color::from_rgba(44 + k, 26 + k / 2, 34 + k / 2, 255);
     crate::props::auto_cube(c + vec3(0.0, 0.08, 0.0), vec3(2.9, 0.16, 2.9), obs(6));
     crate::props::auto_cube(c + vec3(0.0, 0.22, 0.0), vec3(2.3, 0.14, 2.3), obs(14));
     crate::props::auto_cube(c + vec3(0.0, 0.36, 0.0), vec3(1.5, 0.14, 1.5), obs(24));