fix(css): size brand icons to 20x20 (Simple Icons SVGs lack width/height)

Simple Icons ships SVGs with viewBox only — no explicit width/height —
so inline SVG rendered at 0x0 inside the link button flex container.
Add `.link__icon svg { width:20px; height:20px; fill:currentColor }` to
size all icons consistently. Lucide stroke-only icons opt out of the
fill via attribute selector.

themes/bonsai/scripts/capture-screenshots.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+# Capture submission assets (images/screenshot.png + images/tn.png) from
+# the live demo. Run from repo root. Re-runnable; overwrites existing files.
+#
+# Requires: npx (installs Playwright on first run, ~170 MB chromium cache)
+# Optional: oxipng (lossless PNG compression — recommended)
+
+set -euo pipefail
+
+URL="${BONSAI_DEMO_URL:-https://tiennm99.github.io/bonsai/}"
+SCREENSHOT="images/screenshot.png"
+THUMBNAIL="images/tn.png"
+
+cd "$(dirname "$0")/.."
+
+mkdir -p images
+
+echo "==> Installing Playwright Chromium (cached after first run)"
+npx --yes playwright@1.50.0 install chromium
+
+echo "==> Capturing screenshot.png (1500x1000)"
+npx --yes playwright@1.50.0 screenshot \
+  --viewport-size=1500,1000 \
+  --browser=chromium \
+  --color-scheme=light \
+  --wait-for-timeout=800 \
+  "$URL" "$SCREENSHOT"
+
+echo "==> Capturing tn.png (900x600)"
+npx --yes playwright@1.50.0 screenshot \
+  --viewport-size=900,600 \
+  --browser=chromium \
+  --color-scheme=light \
+  --wait-for-timeout=800 \
+  "$URL" "$THUMBNAIL"
+
+if command -v oxipng >/dev/null 2>&1; then
+  echo "==> Compressing with oxipng"
+  oxipng -o4 --strip safe "$SCREENSHOT" "$THUMBNAIL"
+else
+  echo "==> oxipng not installed; skipping compression (install for smaller files)"
+fi
+
+echo "==> Done"
+file "$SCREENSHOT" "$THUMBNAIL"

themes/bonsai/static/css/bonsai.css

@@ -148,6 +148,19 @@ body {
   color: var(--bonsai-accent);
 }
 
+.link__icon svg {
+  width: 20px;
+  height: 20px;
+  display: block;
+  fill: currentColor;
+}
+
+/* Lucide UI icons use stroke, not fill */
+.link__icon svg[stroke="currentColor"],
+.link__icon svg.lucide {
+  fill: none;
+}
+
 .link__title { line-height: 1; }
 
 .bonsai-footer {