diff --git a/pagerite/themes/eyes/banner.css b/pagerite/themes/eyes/banner.css
index 6f89d72..6b35d08 100644
--- a/pagerite/themes/eyes/banner.css
+++ b/pagerite/themes/eyes/banner.css
@@ -1,3 +1,12 @@
 /* Eyes banner design: a canvas critter watching the cursor from the
    grass (banner.html — markup + styles + script inlined by the backend
-   into #page-banner). Fixed-height stage matching the canvas. */
+   into #page-banner). The canvas fills the banner; the scene composes
+   against the 13rem layout box and extends flat grass into any overflow
+   a theme adds below (summer's cross-fade strip). */
+
+/* Opt out of the base parallax (scale overscan + --pry drift): scaling
+   from the bottom edge would crop the top of the composed scene — pushing
+   the critter out of view — and this canvas animates on its own. */
+#page-banner>#eyes {
+  transform: none;
+}
diff --git a/pagerite/themes/eyes/banner.html b/pagerite/themes/eyes/banner.html
index f5dc0c2..cca15a4 100644
--- a/pagerite/themes/eyes/banner.html
+++ b/pagerite/themes/eyes/banner.html
@@ -2,7 +2,7 @@
 <style>
   #eyes {
     width: 100%;
-    height: 240px;
+    height: 100%;
     display: block;
   }
 </style>
@@ -10,19 +10,23 @@
 (() => {
   const c = document.getElementById('eyes')
   const ctx = c.getContext('2d')
-  const DPR = devicePixelRatio || 1
 
-  const fit = () => {
-    const w = Math.max(1, c.clientWidth)
-    const h = Math.max(1, c.clientHeight)
-    c.width = Math.round(w * DPR)
-    c.height = Math.round(h * DPR)
+  // Sync the backing store to the canvas' laid-out size. Checked every
+  // frame: this inline script runs before the stylesheets that size
+  // #page-banner, so observers/load events can still miss the transition.
+  // Assigning width/height also clears the canvas. DPR is read here, not
+  // captured: it changes with browser zoom.
+  const syncSize = () => {
+    const DPR = devicePixelRatio || 1
+    const w = Math.round(Math.max(1, c.clientWidth) * DPR)
+    const h = Math.round(Math.max(1, c.clientHeight) * DPR)
+    if (c.width !== w || c.height !== h) {
+      c.width = w
+      c.height = h
+    }
     ctx.setTransform(DPR, 0, 0, DPR, 0, 0)
   }
 
-  fit()
-  addEventListener('resize', fit)
-
   let mx = 0
   let my = 0
   let lastMove = 0
@@ -69,7 +73,7 @@
   ]
 
   const ridgeY = (x, w, h) =>
-    h * 0.72 +
+    h * 0.83 +
     Math.sin(x * 0.012) * 10 +
     Math.sin(x * 0.003 + 1.4) * 16 +
     Math.sin(x * 0.02 + 0.7) * 3
@@ -129,7 +133,7 @@
 
     for (let i = 0; i < 5; i++) {
       const x = (i + 0.5) * w / 5
-      const y = h * 0.58 + Math.sin(i * 1.7) * 8
+      const y = h * 0.69 + Math.sin(i * 1.7) * 8
 
       ctx.fillStyle = '#5f8d4e'
       ctx.beginPath()
@@ -377,8 +381,17 @@
     const dt = Math.min(now - prev, 100) / 16.7
     prev = now
 
+    syncSize()
+
     const w = c.clientWidth
-    const h = c.clientHeight
+    // Compose the scene against the banner's layout box, not the canvas:
+    // a theme may extend #page-banner past #banner (e.g. summer overflows
+    // the artwork into the page for a masked cross-fade), and the critter
+    // must stay in the visible part. The overflow strip is filled with the
+    // flat meadow color below — a hard canvas edge would show through the
+    // fade, a grass extension just blends.
+    const h = Math.min(c.clientHeight,
+      c.closest('#banner')?.clientHeight || c.clientHeight)
     const R = Math.min(h * 0.11, 38)
 
     if (now > nextMove && !hidePhase) {
@@ -414,6 +427,16 @@
     vy *= Math.pow(0.85, dt)
     yoff += vy * dt
 
+    // Clip the scene to the composed area: the ducking critter travels
+    // below it, and the overflow strip is only flat meadow painted after —
+    // without the clip the critter would leave trails there as it sinks.
+    // Clipping against grass-on-grass is invisible, so the duck still
+    // reads as sinking into the meadow.
+    ctx.save()
+    ctx.beginPath()
+    ctx.rect(0, 0, w, h)
+    ctx.clip()
+
     drawBackground(w, h)
 
     const cx0 = gx * w
@@ -430,6 +453,18 @@
     drawCritter(cx0, eyeY, R, now, dt)
     drawForeground(w, h)
 
+    ctx.restore()
+
+    // Extend the meadow into any overflow below the composed scene, with
+    // the same two layers drawForeground leaves at the bottom (base grass
+    // plus the dark under-band) so the joint is invisible.
+    if (c.clientHeight > h) {
+      ctx.fillStyle = '#69ae4b'
+      ctx.fillRect(0, h, w, c.clientHeight - h)
+      ctx.fillStyle = 'rgba(48,102,34,0.18)'
+      ctx.fillRect(0, h, w, c.clientHeight - h)
+    }
+
     requestAnimationFrame(frame)
   }
 
diff --git a/pagerite/themes/stars/banner.css b/pagerite/themes/stars/banner.css
index ad44a78..9f588e3 100644
--- a/pagerite/themes/stars/banner.css
+++ b/pagerite/themes/stars/banner.css
@@ -1,3 +1,7 @@
 /* Stars banner design: a drifting starfield (banner.html — canvas + script
-   inlined by the backend into #page-banner). Fixed-height stage matching
-   the canvas. */
+   inlined by the backend into #page-banner). The canvas takes the banner's
+   13rem layout height directly so it never renders unclipped before the
+   main stylesheet loads; the starfield scales to any height. The design's
+   opt-out of theme banner overflow/fade effects also lives in banner.html's
+   inline <style>, so it applies atomically with the markup (this file would
+   load a beat later and let the overflow flash through mid-transition). */
diff --git a/pagerite/themes/stars/banner.html b/pagerite/themes/stars/banner.html
index 8812a9c..901bdf4 100644
--- a/pagerite/themes/stars/banner.html
+++ b/pagerite/themes/stars/banner.html
@@ -2,27 +2,47 @@
 <style>
   #stars {
     width: 100%;
-    height: 240px;
+    /* 13rem — the banner's layout height, not 100%: a percentage only
+       resolves after the main stylesheet sizes #page-banner, and until
+       then the canvas would render at its intrinsic height, unclipped,
+       over the page. (This design always opts out of theme overflows —
+       below — so the layout height is always the right one.) */
+    height: 13rem;
     display: block;
   }
+
+  /* The night sky stays a windowed stage: undo the summer theme's banner
+     overflow/cross-fade — a starfield must not bleed into a daylit page.
+     Kept in this inlined <style> (not banner.css) so the opt-out applies
+     atomically with the markup; a separate stylesheet can arrive a beat
+     later and let the overflow flash through mid-transition. Later in
+     document order than theme.css, so same-specificity rules win. */
+  #page-banner {
+    inset: 0;
+    mask-image: none;
+  }
 </style>
 <script><!--
 (() => {
   const c = document.getElementById('stars')
   const ctx = c.getContext('2d')
-  const DPR = devicePixelRatio || 1
 
-  const fit = () => {
-    const w = Math.max(1, c.clientWidth)
-    const h = Math.max(1, c.clientHeight)
-    c.width = Math.round(w * DPR)
-    c.height = Math.round(h * DPR)
+  // Sync the backing store to the canvas' laid-out size. Checked every
+  // frame: this inline script runs before the stylesheets that size
+  // #page-banner, so observers/load events can still miss the transition.
+  // Assigning width/height also clears the canvas. DPR is read here, not
+  // captured: it changes with browser zoom.
+  const syncSize = () => {
+    const DPR = devicePixelRatio || 1
+    const w = Math.round(Math.max(1, c.clientWidth) * DPR)
+    const h = Math.round(Math.max(1, c.clientHeight) * DPR)
+    if (c.width !== w || c.height !== h) {
+      c.width = w
+      c.height = h
+    }
     ctx.setTransform(DPR, 0, 0, DPR, 0, 0)
   }
 
-  fit()
-  addEventListener('resize', fit)
-
   const stars = Array.from({ length: 110 }, () => ({
     x: Math.random(),
     y: Math.random(),
@@ -33,6 +53,7 @@
   let prev = performance.now()
   ;(function frame(now) {
     if (!c.isConnected) return
+    syncSize()
     const w = c.clientWidth
     const h = c.clientHeight
     const dt = Math.min(now - prev, 100)
diff --git a/pagerite/themes/summer/theme.css b/pagerite/themes/summer/theme.css
index ee071c0..107bbf7 100644
--- a/pagerite/themes/summer/theme.css
+++ b/pagerite/themes/summer/theme.css
@@ -62,10 +62,29 @@ body {
   color: #3d5223;
 }
 
-/* The banner frame ties into the meadow beneath it. */
+/* No separation between banner and page: the frame loses its background,
+   border and shadow, and the artwork overflows into the document below,
+   masked by a transparency gradient so it cross-fades into the body's fixed
+   meadow gradient. A plain color match is impossible — both sides are
+   gradients, and the parallax drift keeps the banner side moving. */
 #banner {
-  border-bottom-color: #4f913b30;
-  box-shadow: 0 0.3rem 1rem #4f913b22;
+  background: none;
+  border-bottom: 0;
+  box-shadow: none;
+}
+
+#page-banner {
+  inset: 0 0 -6rem;
+  /* Paints over the page background in the overlap, but never swallows its
+     clicks. */
+  pointer-events: none;
+  mask-image: linear-gradient(180deg, #000 calc(100% - 6rem), transparent);
+}
+
+/* The mask above replaced the SVG's flat-color bottom fade (meadowFade) —
+   fading to a single --bg would reintroduce a seam against the gradient. */
+#page-banner .summer-fade {
+  stop-opacity: 0;
 }
 
 /* Cheerful oversized tilted brand in a sky→grass→flower gradient. */
@@ -115,14 +134,26 @@ body {
 }
 
 /* Content sits in a soft wash of sunlit meadow rather than on a white
-   card. */
+   card. The wash lives on a pseudo-element so it can carry a vertical
+   mask: it fades in from transparent over the strip where the banner
+   artwork overflows into the page, so the two never fight — no matter
+   which side paints on top. */
 main {
+  position: relative;
+}
+
+main::before {
+  content: "";
+  position: absolute;
+  inset: 0;
+  z-index: -1;
   background: linear-gradient(90deg,
       transparent,
       #f0f8dc80 15%,
       #f0f8dc8c 50%,
       #f0f8dc80 85%,
       transparent);
+  mask-image: linear-gradient(180deg, transparent, #000 6rem);
 }
 
 /* The sidebar is a piece of the same meadow: glassy green with a light
@@ -132,6 +163,8 @@ main {
   border-right: 1px solid #ffffff80;
   border-bottom: 1px solid var(--line);
   box-shadow: 0 0.3rem 1rem #4f913b1f;
+  border-radius: 1rem;
+  margin-inline: 0.5rem;
 }
 
 #sidebar a {