diff --git a/README.md b/README.md
index 27f46ac..a5329ad 100644
--- a/README.md
+++ b/README.md
@@ -206,6 +206,8 @@ default ("light"): running CSS animations repaint the whole drawing every frame,
 which keeps a slow laptop busy. The ▷ button in the view toolbar switches
 between light, smooth and off, and the browser remembers the choice. In
 `isokit.toml`, `[build] animation = "smooth"` sets the default for built pages.
+When the system asks for less motion (Windows: Settings → Accessibility →
+Visual effects → Animation effects off), views start still; ▷ turns them on.
 
 ## Commands
 
diff --git a/tools/check_web.py b/tools/check_web.py
index a626995..fc39f7d 100644
--- a/tools/check_web.py
+++ b/tools/check_web.py
@@ -326,6 +326,26 @@ try:
         check("(from robot-b)" in loads and flips == 32, f"robot arms pass the goods on ({flips} poses): " + loads)
         shot(pg, "web-factory.jpg")
 
+        # ---------------------------------------------------------------- a system asking for less motion
+        # (Windows: Animation effects off): the view starts still, but the button stays and turns it on
+        rctx = b.new_context(viewport={"width": 1200, "height": 800}, reduced_motion="reduce")
+        rp = rctx.new_page()
+        rp.goto(BASE)
+        ready(rp)
+        rp.wait_for_timeout(500)
+        ride = "() => Array.from(document.querySelectorAll('.iso-svg .iso-a')).map(e => getComputedStyle(e).transform + getComputedStyle(e).opacity).join('|')"
+        moves = lambda: (lambda a: (rp.wait_for_timeout(700), a != rp.evaluate(ride))[1])(rp.evaluate(ride))
+        check(rp.evaluate("() => __studio.view.animation()") == "off" and rp.locator('.iso-bar [data-a="anim"]').is_visible() and not moves(),
+              "reduced motion: the view starts still, with the animation button there")
+        rp.locator('.iso-bar [data-a="anim"]').click()
+        rp.wait_for_timeout(500)
+        check(rp.evaluate("() => __studio.view.animation()") == "light" and moves(), "one click turns animation on despite reduced motion")
+        rp.reload()
+        ready(rp)
+        rp.wait_for_timeout(500)
+        check(rp.evaluate("() => __studio.view.animation()") == "light" and moves(), "and the choice is remembered")
+        rctx.close()
+
         # ---------------------------------------------------------------- folder project (OPFS stands in for a picked folder)
         demo = {f.relative_to(ROOT / "examples" / "demo").as_posix(): f.read_text(encoding="utf-8")
                 for f in (ROOT / "examples" / "demo").rglob("*") if f.is_file() and "dist" not in f.parts}
diff --git a/viewer/isokit-view.css b/viewer/isokit-view.css
index 30883e2..2b72066 100644
--- a/viewer/isokit-view.css
+++ b/viewer/isokit-view.css
@@ -160,10 +160,11 @@ html[data-theme=light] .iso-svg .iso-glint { display: inline; }
   92% { transform: translate(var(--dx), var(--dy)); opacity: 1; }
   96%, 100% { transform: translate(var(--dx), var(--dy)); opacity: 0; }
 }
+/* a system asking for less motion: still pictures, until the viewer turns animation on (iso-anim-on) */
 @media (prefers-reduced-motion: reduce) {
-  .iso-svg .iso-a, .iso-svg .iso-ledr, .iso-svg .iso-ledo { animation: none !important; }
-  .iso-svg .iso-puff, .iso-svg .iso-puff2, .iso-svg .iso-smoke, .iso-svg .iso-disc, .iso-svg .iso-glint, .iso-svg .iso-rip { display: none; }
-  .iso-svg .iso-park { display: inline; }
+  .iso-wrap:not(.iso-anim-on) .iso-svg .iso-a, .iso-wrap:not(.iso-anim-on) .iso-svg .iso-ledr, .iso-wrap:not(.iso-anim-on) .iso-svg .iso-ledo { animation: none !important; }
+  .iso-wrap:not(.iso-anim-on) .iso-svg :is(.iso-puff, .iso-puff2, .iso-smoke, .iso-disc, .iso-glint, .iso-rip) { display: none; }
+  .iso-wrap:not(.iso-anim-on) .iso-svg .iso-park { display: inline; }
 }
 @media (max-width: 640px) {
   .iso-stage { aspect-ratio: 1 / 1; min-height: 320px; }
diff --git a/viewer/isokit-view.js b/viewer/isokit-view.js
index ac85ab7..286aa8a 100644
--- a/viewer/isokit-view.js
+++ b/viewer/isokit-view.js
@@ -138,24 +138,32 @@
     // CSS animations inside the drawing repaint all of it every frame: a fifth of a fast core,
     // all of a slow one. "light" (the default) pauses them and steps them on together about ten
     // times a second, "smooth" lets them run, "off" stops them. Pan and zoom gestures pause them.
+    // A system asking for less motion (Windows: Animation effects off) starts them off, but the
+    // button stays: what the viewer picks there wins and is remembered.
+    var reducedMotion = !!(window.matchMedia && window.matchMedia("(prefers-reduced-motion: reduce)").matches);
     var ANIM = ["light", "smooth", "off"], ANIM_UI = {
       light: ["\u25B7", "Animation: light, about 10 steps a second (click: smooth)"],
       smooth: ["\u25B6", "Animation: smooth (click: off)"],
-      off: ["\u2016", "Animation: off (click: light)"]
+      off: ["\u2016", reducedMotion ? "Animation: off, as your system asks for less motion (click: on)" : "Animation: off (click: light)"]
     };
     var animMode = (function () {
       var m = null;
       try { m = localStorage.getItem("isokit-anim"); } catch (e) { /* storage blocked */ }
-      return ANIM.indexOf(m) >= 0 ? m : ANIM.indexOf(opts.animation) >= 0 ? opts.animation : "light";
+      if (ANIM.indexOf(m) >= 0) return m;
+      if (reducedMotion) return "off";
+      return ANIM.indexOf(opts.animation) >= 0 ? opts.animation : "light";
     })();
-    var animTimer = 0, animLast = 0, animList = [], animBtn = bar.querySelector('[data-a="anim"]');
-    var reducedMotion = !!(window.matchMedia && window.matchMedia("(prefers-reduced-motion: reduce)").matches);
+    // animScripted: the animations of this drawing were paused by script (light mode) and ignore
+    // CSS play states from then on, so smooth needs the scene drawn again
+    var animTimer = 0, animLast = 0, animList = [], animScripted = false, animBtn = bar.querySelector('[data-a="anim"]');
     // after every new scene and every mode change
     function animSetup() {
       clearInterval(animTimer); animTimer = 0; animList = [];
       wrap.classList.toggle("iso-anim-off", animMode === "off");
+      // the viewer turned them on: past the reduced-motion rules in the CSS
+      wrap.classList.toggle("iso-anim-on", animMode !== "off");
       if (animBtn) {
-        animBtn.hidden = reducedMotion || !svg.querySelector(".iso-a, .iso-drive, .iso-ledr, .iso-ledo");
+        animBtn.hidden = !svg.querySelector(".iso-a, .iso-drive, .iso-ledr, .iso-ledo");
         animBtn.textContent = ANIM_UI[animMode][0]; animBtn.title = ANIM_UI[animMode][1];
         animBtn.setAttribute("aria-label", ANIM_UI[animMode][1]);
       }
@@ -163,6 +171,7 @@
       animList = svg.getAnimations({ subtree: true });
       if (!animList.length) return;
       animList.forEach(function (a) { a.pause(); });
+      animScripted = true;
       animLast = performance.now();
       animTimer = setInterval(animStep, 100);
     }
@@ -178,7 +187,7 @@
       animMode = m;
       try { localStorage.setItem("isokit-anim", m); } catch (e) { /* storage blocked */ }
       // animations paused by script ignore CSS from then on: draw the scene again to let them run
-      if (was === "light" && m === "smooth" && scn) applyScene(scn); else animSetup();
+      if (m === "smooth" && animScripted && scn) applyScene(scn); else animSetup();
       call(opts.onAnimation, m);
     }
 
@@ -215,7 +224,7 @@
       var hadScene = !!scn;
       scn = d;
       svg.innerHTML = d.html;
-      lastK = null;
+      lastK = null; animScripted = false;
       wrap.classList.toggle("iso-still", st.cfg.running === false);
       metas = Array.prototype.map.call(svg.querySelectorAll(".iso-tag"), function (g, i) {
         return { el: g, p: +g.getAttribute("data-p"), w: +g.getAttribute("data-w"), x: +g.getAttribute("data-x"), y: +g.getAttribute("data-y"), i: i, hid: false };