diff --git a/README.md b/README.md
index df319ce..a99ce23 100644
--- a/README.md
+++ b/README.md
@@ -23,7 +23,7 @@ Physilinks is a browser-based physics linking game built with Matter.js. Match a
 ## File structure
 - `index.html`: Shell layout and HUD overlays; loads Matter.js plus game scripts.
 - `styles.css`: Styling for canvas, HUD, overlays, and score popups.
-- `scenes.js`: Scene presets and per-scene static body factories.
+- `scenes/`: Scene presets split per file (`scene-*.js`) plus `index.js` that registers them to `window.PhysilinksScenes`.
 - `ui.js`: DOM access, HUD updates, overlays, popups, and control/selector wiring.
 - `main.js`: Physics setup, state machine, chain interaction, spawning, scene application, and pause/restart logic.
 
diff --git a/index.html b/index.html
index 1089d60..5cf76dc 100644
--- a/index.html
+++ b/index.html
@@ -92,7 +92,11 @@
         </div>
 
         <script src="https://unpkg.com/matter-js@0.19.0/build/matter.min.js"></script>
-        <script src="./scenes.js"></script>
+        <script src="./scenes/scene-grid.js"></script>
+        <script src="./scenes/scene-balanced.js"></script>
+        <script src="./scenes/scene-lowg.js"></script>
+        <script src="./scenes/scene-fastdrop.js"></script>
+        <script src="./scenes/index.js"></script>
         <script src="./ui.js"></script>
         <script src="./main.js"></script>
     </body>
diff --git a/scenes/index.js b/scenes/index.js
new file mode 100644
index 0000000..a302828
--- /dev/null
+++ b/scenes/index.js
@@ -0,0 +1,10 @@
+(() => {
+  const scenes = window.PhysilinksSceneDefs || [];
+  const gridDefault = scenes.find((s) => s.id === "scene-grid");
+  const defaultSceneId = gridDefault?.id || scenes[0]?.id || "scene-grid";
+
+  window.PhysilinksScenes = {
+    scenes,
+    defaultSceneId,
+  };
+})();
diff --git a/scenes/scene-balanced.js b/scenes/scene-balanced.js
new file mode 100644
index 0000000..d479d8d
--- /dev/null
+++ b/scenes/scene-balanced.js
@@ -0,0 +1,91 @@
+(() => {
+  const { Bodies } = Matter;
+  const scenes =
+    (window.PhysilinksSceneDefs = window.PhysilinksSceneDefs || []);
+
+  scenes.push({
+    id: "scene1",
+    name: "Balanced",
+    config: {
+      gravity: 0.88,
+      spawnIntervalMs: 520,
+      minChain: 3,
+      palette: ["#ff595e", "#ffca3a", "#8ac926", "#1982c4", "#6a4c93"],
+      ballRadius: 38,
+      link: {
+        stiffness: 0.85,
+        lengthScale: 1.05,
+        damping: 0.08,
+        lineWidth: 3,
+        rope: true,
+        renderType: "line",
+        maxLengthMultiplier: 3.2,
+      },
+    },
+    createBodies: (w, h) => {
+      const floorHeight = Math.max(60, h * 0.12);
+      const wallThickness = Math.max(32, w * 0.05);
+      const wallHeight = h * 1.6;
+      const platformHeight = Math.max(14, h * 0.025);
+      const smallPlatformWidth = Math.max(140, w * 0.18);
+      const largePlatformWidth = Math.max(180, w * 0.22);
+      return [
+        Bodies.rectangle(
+          w / 2,
+          h + floorHeight / 2,
+          w + wallThickness * 2,
+          floorHeight,
+          {
+            isStatic: true,
+            restitution: 0.8,
+            render: { fillStyle: "#0ea5e9", strokeStyle: "#0ea5e9" },
+          },
+        ),
+        Bodies.rectangle(
+          -wallThickness / 2,
+          h / 2,
+          wallThickness,
+          wallHeight,
+          {
+            isStatic: true,
+            render: { fillStyle: "#f97316", strokeStyle: "#f97316" },
+          },
+        ),
+        Bodies.rectangle(
+          w + wallThickness / 2,
+          h / 2,
+          wallThickness,
+          wallHeight,
+          {
+            isStatic: true,
+            render: { fillStyle: "#f97316", strokeStyle: "#f97316" },
+          },
+        ),
+        Bodies.rectangle(
+          w * 0.25,
+          h * 0.55,
+          smallPlatformWidth,
+          platformHeight,
+          {
+            isStatic: true,
+            angle: -0.3,
+            render: { fillStyle: "#22c55e", strokeStyle: "#22c55e" },
+            plugin: { rotSpeed: 0.1 },
+          },
+        ),
+        Bodies.rectangle(
+          w * 0.7,
+          h * 0.4,
+          largePlatformWidth,
+          platformHeight * 1.2,
+          {
+            isStatic: true,
+            angle: 0.26,
+            render: { fillStyle: "#a855f7", strokeStyle: "#a855f7" },
+            plugin: { rotSpeed: -0.08 },
+          },
+        ),
+      ];
+    },
+  });
+})();
diff --git a/scenes/scene-fastdrop.js b/scenes/scene-fastdrop.js
new file mode 100644
index 0000000..2524bad
--- /dev/null
+++ b/scenes/scene-fastdrop.js
@@ -0,0 +1,98 @@
+(() => {
+  const { Bodies } = Matter;
+  const scenes =
+    (window.PhysilinksSceneDefs = window.PhysilinksSceneDefs || []);
+
+  scenes.push({
+    id: "scene3",
+    name: "Fast drop maze",
+    config: {
+      gravity: 1.25,
+      spawnIntervalMs: 220,
+      minChain: 3,
+      palette: ["#e879f9", "#38bdf8", "#f97316", "#22c55e"],
+      ballRadius: 16,
+      link: {
+        stiffness: 1,
+        lengthScale: 0.85,
+        damping: 0.15,
+        lineWidth: 3,
+        rope: false,
+        renderType: "line",
+        maxLengthMultiplier: 23.8,
+      },
+    },
+    createBodies: (w, h) => {
+      const floorHeight = Math.max(60, h * 0.1);
+      const wallThickness = Math.max(28, w * 0.045);
+      const wallHeight = h * 1.5;
+      const pegRadius = Math.max(10, Math.min(22, Math.min(w, h) * 0.03));
+      const platformHeight = Math.max(12, h * 0.02);
+      const leftPlatformWidth = Math.max(120, w * 0.16);
+      const rightPlatformWidth = Math.max(130, w * 0.18);
+      const bodies = [
+        Bodies.rectangle(
+          w / 2,
+          h + floorHeight / 2,
+          w + wallThickness * 2,
+          floorHeight,
+          {
+            isStatic: true,
+            restitution: 0.75,
+            render: { fillStyle: "#14b8a6", strokeStyle: "#14b8a6" },
+          },
+        ),
+        Bodies.rectangle(
+          -wallThickness / 2,
+          h / 2,
+          wallThickness,
+          wallHeight,
+          {
+            isStatic: true,
+            render: { fillStyle: "#f472b6", strokeStyle: "#f472b6" },
+          },
+        ),
+        Bodies.rectangle(
+          w + wallThickness / 2,
+          h / 2,
+          wallThickness,
+          wallHeight,
+          {
+            isStatic: true,
+            render: { fillStyle: "#f472b6", strokeStyle: "#f472b6" },
+          },
+        ),
+      ];
+      for (let i = 0; i < 5; i += 1) {
+        const x = (w * (i + 1)) / 6;
+        const y = h * 0.35 + (i % 2 === 0 ? h * 0.06 : -h * 0.05);
+        bodies.push(
+          Bodies.circle(x, y, pegRadius, {
+            isStatic: true,
+            restitution: 0.9,
+            render: { fillStyle: "#facc15", strokeStyle: "#facc15" },
+          }),
+        );
+      }
+      bodies.push(
+        Bodies.rectangle(w * 0.3, h * 0.55, leftPlatformWidth, platformHeight, {
+          isStatic: true,
+          angle: -0.3,
+          render: { fillStyle: "#8b5cf6", strokeStyle: "#8b5cf6" },
+        }),
+        Bodies.rectangle(
+          w * 0.7,
+          h * 0.58,
+          rightPlatformWidth,
+          platformHeight * 1.05,
+          {
+            isStatic: true,
+            angle: 0.28,
+            render: { fillStyle: "#10b981", strokeStyle: "#10b981" },
+          },
+        ),
+      );
+      return bodies;
+    },
+  });
+})();
diff --git a/scenes/scene-grid.js b/scenes/scene-grid.js
new file mode 100644
index 0000000..760827b
--- /dev/null
+++ b/scenes/scene-grid.js
@@ -0,0 +1,129 @@
+(() => {
+  const { Bodies } = Matter;
+  const scenes = (window.PhysilinksSceneDefs =
+    window.PhysilinksSceneDefs || []);
+
+  scenes.push({
+    id: "scene-grid",
+    name: "Zero-G Grid (default)",
+    config: {
+      gravity: 0,
+      spawnIntervalMs: 0,
+      autoSpawn: false,
+      minChain: 3,
+      palette: ["#38bdf8", "#f472b6", "#facc15", "#34d399", "#a78bfa"],
+      ballRadius: 24,
+      gridPadding: 0.08, // percent of viewport padding applied to both axes
+      gridBallScale: 0.38, // percent of cell size used as radius
+      gridLegend: {
+        A: "#38bdf8",
+        B: "#f472b6",
+        C: "#facc15",
+        D: "#34d399",
+        E: "#a78bfa",
+      },
+      winCondition: {
+        type: "clearCount",
+        target: 25,
+        nextSceneId: "scene1",
+        onWin: { setGravity: 0.88 },
+      },
+      gridLayouts: [
+        [
+          "AABBBBAA",
+          "ACCCBCCA",
+          "ACDDDDCA",
+          "ACEEEECA",
+          "ACEEEECA",
+          "ACDDDDCA",
+          "ACCCBCCA",
+          "AABBBBAA",
+        ],
+        [
+          "AAAABBBA",
+          "ABBBCCCA",
+          "ABCDDDCA",
+          "ABCEEECA",
+          "ABCEEECA",
+          "ABCDDDCA",
+          "ABBBCCCA",
+          "AAAABBBA",
+        ],
+        [
+          "AABBCCDD",
+          "ABBCCDEE",
+          "ABCCDEEA",
+          "ACCDDEEA",
+          "ACCDDEEA",
+          "ABCCDEEA",
+          "ABBCCDEE",
+          "AABBCCDD",
+        ],
+      ],
+      link: {
+        stiffness: 0.82,
+        lengthScale: 1.05,
+        damping: 0.06,
+        lineWidth: 3,
+        rope: true,
+        renderType: "line",
+        maxLengthMultiplier: 3.8,
+      },
+    },
+    createBodies: (w, h) => {
+      const pad = 0.08;
+      const usableW = w * (1 - pad * 2);
+      const usableH = h * (1 - pad * 2);
+      const gridSize = Math.min(usableW, usableH);
+      const gridX = (w - gridSize) / 2;
+      const gridY = (h - gridSize) / 2;
+      const wallThickness = Math.max(18, gridSize * 0.045);
+      const innerW = gridSize;
+      const innerH = gridSize;
+      const cx = gridX + innerW / 2;
+      const cy = gridY + innerH / 2;
+      return [
+        Bodies.rectangle(
+          cx,
+          gridY - wallThickness / 2,
+          innerW + wallThickness * 2,
+          wallThickness,
+          {
+            isStatic: true,
+            render: { fillStyle: "#0b1222", strokeStyle: "#0b1222" },
+          },
+        ),
+        Bodies.rectangle(
+          cx,
+          gridY + innerH + wallThickness / 2,
+          innerW + wallThickness * 2,
+          wallThickness,
+          {
+            isStatic: true,
+            render: { fillStyle: "#0b1222", strokeStyle: "#0b1222" },
+          },
+        ),
+        Bodies.rectangle(
+          gridX - wallThickness / 2,
+          cy,
+          wallThickness,
+          innerH + wallThickness * 2,
+          {
+            isStatic: true,
+            render: { fillStyle: "#0b1222", strokeStyle: "#0b1222" },
+          },
+        ),
+        Bodies.rectangle(
+          gridX + innerW + wallThickness / 2,
+          cy,
+          wallThickness,
+          innerH + wallThickness * 2,
+          {
+            isStatic: true,
+            render: { fillStyle: "#0b1222", strokeStyle: "#0b1222" },
+          },
+        ),
+      ];
+    },
+  });
+})();
diff --git a/scenes/scene-lowg.js b/scenes/scene-lowg.js
new file mode 100644
index 0000000..f3a1f82
--- /dev/null
+++ b/scenes/scene-lowg.js
@@ -0,0 +1,83 @@
+(() => {
+  const { Bodies } = Matter;
+  const scenes =
+    (window.PhysilinksSceneDefs = window.PhysilinksSceneDefs || []);
+
+  scenes.push({
+    id: "scene2",
+    name: "Low-G terraces",
+    config: {
+      gravity: 0.65,
+      spawnIntervalMs: 600,
+      minChain: 3,
+      palette: ["#fb7185", "#fbbf24", "#34d399", "#38bdf8"],
+      ballRadius: 22,
+      link: {
+        stiffness: 0.6,
+        lengthScale: 1,
+        damping: 0.01,
+        lineWidth: 4,
+        rope: false,
+        renderType: "spring",
+        maxLengthMultiplier: 4.7,
+      },
+    },
+    createBodies: (w, h) => {
+      const floorHeight = Math.max(70, h * 0.12);
+      const wallThickness = Math.max(32, w * 0.05);
+      const wallHeight = h * 1.8;
+      const ledgeHeight = Math.max(14, h * 0.022);
+      const leftWidth = Math.max(160, w * 0.18);
+      const midWidth = Math.max(190, w * 0.26);
+      const rightWidth = Math.max(150, w * 0.18);
+      return [
+        Bodies.rectangle(
+          w / 2,
+          h + floorHeight / 2,
+          w + wallThickness * 2,
+          floorHeight,
+          {
+            isStatic: true,
+            restitution: 0.9,
+            render: { fillStyle: "#0ea5e9", strokeStyle: "#0ea5e9" },
+          },
+        ),
+        Bodies.rectangle(
+          -wallThickness / 2,
+          h / 2,
+          wallThickness,
+          wallHeight,
+          {
+            isStatic: true,
+            render: { fillStyle: "#7c3aed", strokeStyle: "#7c3aed" },
+          },
+        ),
+        Bodies.rectangle(
+          w + wallThickness / 2,
+          h / 2,
+          wallThickness,
+          wallHeight,
+          {
+            isStatic: true,
+            render: { fillStyle: "#7c3aed", strokeStyle: "#7c3aed" },
+          },
+        ),
+        Bodies.rectangle(w * 0.2, h * 0.45, leftWidth, ledgeHeight, {
+          isStatic: true,
+          angle: 0.08,
+          render: { fillStyle: "#f97316", strokeStyle: "#f97316" },
+        }),
+        Bodies.rectangle(w * 0.5, h * 0.6, midWidth, ledgeHeight, {
+          isStatic: true,
+          angle: -0.04,
+          render: { fillStyle: "#14b8a6", strokeStyle: "#14b8a6" },
+        }),
+        Bodies.rectangle(w * 0.8, h * 0.42, rightWidth, ledgeHeight, {
+          isStatic: true,
+          angle: 0.14,
+          render: { fillStyle: "#c084fc", strokeStyle: "#c084fc" },
+        }),
+      ];
+    },
+  });
+})();