diff --git a/frontend/packages/agent/src/agent.css b/frontend/packages/agent/src/agent.css
index 2b9d7007..28519eb4 100644
--- a/frontend/packages/agent/src/agent.css
+++ b/frontend/packages/agent/src/agent.css
@@ -891,34 +891,83 @@ pre.diff {
 /* Row + pill + details styling moved to hive-fr0nt::TERMINAL_CSS. */
 
 /* ─── side panel (singleton drawer) ────────────────────────────────
-   Inbox + loose-ends details open here instead of expanding inline. The
-   drawer chrome itself (backdrop, drawer, resize handle, header, title,
-   close button) is now the shared `<hive-side-panel>` element
-   (@hive/shared/side-panel.js — this also picks up drag-to-resize,
-   which this page didn't have before); what's left here is the drag
-   cursor-override escape hatch (has to be a global, light-DOM rule — it
-   reaches every element on the page during a drag, not just the shared
-   element's own shadow tree) and the styling for the panel's own
-   content types, which the shared element's shadow tree can never
-   reach (see @hive/shared/side-panel/hive-side-panel.css's header
-   comment). The `hive-side-panel .agent-inbox …` rules below use the
-   element's own tag name as the selector root — no compatibility class
-   needed, the tag name already uniquely identifies the light-DOM
-   instance app.js's `sidePanel` creates. */
-body.side-panel-resizing {
-  user-select: none;
+   Inbox + loose-ends details open here instead of expanding inline.
+   Copy of the dashboard's side-panel pattern — candidate for
+   extraction into @hive/shared once both surfaces stabilize. */
+.side-panel {
+  position: fixed;
+  inset: 0;
+  z-index: 50;
+  /* Closed: ignore pointer events so the agent page underneath stays
+     interactive; `.open` flips it back on. */
+  pointer-events: none;
+}
+.side-panel-backdrop {
+  position: absolute;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.55);
+  opacity: 0;
+  transition: opacity 0.2s ease;
+}
+.side-panel-drawer {
+  position: absolute;
+  top: 0;
+  right: 0;
+  bottom: 0;
+  width: min(640px, 92vw);
+  display: flex;
+  flex-direction: column;
+  background: var(--bg-elev);
+  border-left: 2px solid var(--purple);
+  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.45);
+  transform: translateX(100%);
+  transition: transform 0.25s ease;
+}
+.side-panel.open { pointer-events: auto; }
+.side-panel.open .side-panel-backdrop { opacity: 1; }
+.side-panel.open .side-panel-drawer { transform: translateX(0); }
+.side-panel-head {
+  flex: 0 0 auto;
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 1em;
+  padding: 0.7em 1em;
+  border-bottom: 1px solid var(--border);
+}
+.side-panel-title {
+  color: var(--purple);
+  font-weight: bold;
+  letter-spacing: 0.05em;
+  word-break: break-all;
+}
+.side-panel-close {
+  flex: 0 0 auto;
+  background: var(--bg);
+  color: var(--fg);
+  border: 1px solid var(--border);
+  font-family: inherit;
+  font-size: 1em;
+  line-height: 1;
+  padding: 0.25em 0.55em;
+  cursor: pointer;
+}
+.side-panel-close:hover { border-color: var(--red); color: var(--red); }
+.side-panel-body {
+  flex: 1 1 auto;
+  overflow: auto;
+  padding: 0.8em 1em;
 }
-body.side-panel-resizing * { cursor: ew-resize !important; }
 /* Inbox / loose-ends lists rendered into the side-panel body. The
    legacy <details>-collapsible variant of .agent-inbox is gone, so
    here we strip the inbox-only chrome (background, border-left) and
    let the panel body's own padding own the framing. */
-hive-side-panel .agent-inbox {
+.side-panel-body .agent-inbox {
   margin: 0;
   font-size: inherit;
   color: var(--fg);
 }
-hive-side-panel .agent-inbox ul {
+.side-panel-body .agent-inbox ul {
   background: transparent;
   border-left: 0;
   padding: 0;
diff --git a/frontend/packages/agent/src/app.js b/frontend/packages/agent/src/app.js
index 729e4b06..c650910e 100644
--- a/frontend/packages/agent/src/app.js
+++ b/frontend/packages/agent/src/app.js
@@ -6,7 +6,6 @@ import { create as termCreate, linkify as termLinkify } from '@hive/shared/termi
 import { asyncBtn, bindAsyncForms } from '@hive/shared/forms.js';
 import { themedConfirm } from '@hive/shared/modal.js';
 import { el } from '@hive/shared/dom.js';
-import '@hive/shared/side-panel.js'; // registers <hive-side-panel> — side-effect import
 import { marked } from 'marked';
 import DOMPurify from 'dompurify';
 
@@ -38,17 +37,43 @@ window.marked = marked;
   bindAsyncForms(() => refreshState());
 
   // ─── side panel (singleton drawer for inbox + loose-ends flyouts) ──────
-  // The shared `<hive-side-panel>` element (see @hive/shared/side-panel.js
-  // for the chrome/behavior it owns), created once, eagerly, when this
-  // module's IIFE runs (ES modules execute after the document is
-  // parsed, so `document.body` already exists). Used directly — this
-  // UI's opens always take an owner name, so call sites use the
-  // element's own `openNamed(name, title, content)` rather than the
-  // untyped `open`. `agent.css` reaches the slotted content via a plain
-  // `hive-side-panel .agent-inbox …` tag-name selector (no compat class
-  // needed — the element's own tag name already identifies it).
-  const sidePanel = document.createElement('hive-side-panel');
-  document.body.append(sidePanel);
+  // Shared shape with the dashboard's panel. Candidate for extraction
+  // into @hive/shared once both surfaces stabilise.
+  const Panel = (() => {
+    const root = $('side-panel');
+    const titleEl = $('side-panel-title');
+    const bodyEl = $('side-panel-body');
+    /** Owner key (e.g. 'inbox', 'loose-ends'). Refresh hooks check
+     *  against this so a live event only re-renders the panel when
+     *  the matching view is actually visible. null when closed. */
+    let owner = null;
+    function open(name, title, content) {
+      owner = name;
+      titleEl.textContent = title;
+      bodyEl.replaceChildren(...(content ? [content] : []));
+      root.classList.add('open');
+      root.setAttribute('aria-hidden', 'false');
+    }
+    function close() {
+      owner = null;
+      root.classList.remove('open');
+      root.setAttribute('aria-hidden', 'true');
+    }
+    function refresh(name, title, content) {
+      if (owner !== name) return;
+      titleEl.textContent = title;
+      bodyEl.replaceChildren(...(content ? [content] : []));
+    }
+    function bind() {
+      $('side-panel-close').addEventListener('click', close);
+      $('side-panel-backdrop').addEventListener('click', close);
+      document.addEventListener('keydown', (e) => {
+        if (e.key === 'Escape' && root.classList.contains('open')) close();
+      });
+    }
+    return { open, close, refresh, bind, currentOwner: () => owner };
+  })();
+  Panel.bind();
 
   // Wire the header pills to open the side panel. Pre-built (vs
   // re-building per-click) so the freshest snapshot already lives
@@ -58,14 +83,14 @@ window.marked = marked;
     const inboxPill = $('inbox-pill');
     if (inboxPill) {
       inboxPill.addEventListener('click', () => {
-        sidePanel.openNamed('inbox', 'inbox · ' + lastInbox.length,
+        Panel.open('inbox', 'inbox · ' + lastInbox.length,
           buildInboxList(lastInbox));
       });
     }
     const todosPill = $('todos-pill');
     if (todosPill) {
       todosPill.addEventListener('click', () => {
-        sidePanel.openNamed('todos', 'todos · ' + lastTodos.length,
+        Panel.open('todos', 'todos · ' + lastTodos.length,
           buildTodosList(lastTodos));
       });
     }
@@ -327,7 +352,7 @@ window.marked = marked;
     else closeOverflowMenu();
   }
   // Wire once on boot. The trigger itself + click-outside + Escape
-  // dismissal pattern matches the side-panel flyout (sidePanel).
+  // dismissal pattern matches the side-panel flyout (Panel).
   (function bindOverflowMenu() {
     const btn = $('overflow-btn');
     if (!btn) return;
@@ -798,7 +823,7 @@ window.marked = marked;
   function buildLooseEndsList(threads) {
     // Returns the <div> the side panel renders. The structural shape
     // mirrors the legacy <details>-collapsible block — same CSS rules
-    // apply via `hive-side-panel .agent-inbox`.
+    // apply via `.side-panel-body .agent-inbox`.
     const wrap = el('div', { class: 'agent-inbox' });
     if (!threads.length) {
       wrap.append(el('p', { class: 'side-panel-empty' },
@@ -898,7 +923,7 @@ window.marked = marked;
     const count = $('todos-count');
     if (count) count.textContent = todos.length;
     if (pill) pill.hidden = todos.length === 0;
-    sidePanel.refresh('todos', 'todos · ' + todos.length,
+    Panel.refresh('todos', 'todos · ' + todos.length,
       buildTodosList(todos));
   }
 
@@ -1064,7 +1089,7 @@ window.marked = marked;
     const count = $('inbox-count');
     if (count) count.textContent = rows.length;
     if (pill) pill.hidden = rows.length === 0;
-    sidePanel.refresh('inbox', 'inbox · ' + rows.length, buildInboxList(rows));
+    Panel.refresh('inbox', 'inbox · ' + rows.length, buildInboxList(rows));
   }
   // Harness reachability badge: derived from the same `s.status` the
   // status block reads. Each status maps to a glyph + label + colour
diff --git a/frontend/packages/agent/src/index.html b/frontend/packages/agent/src/index.html
index 86686717..0e1c1d68 100644
--- a/frontend/packages/agent/src/index.html
+++ b/frontend/packages/agent/src/index.html
@@ -93,10 +93,21 @@
     <div id="term-input" class="term-input"></div>
   </footer>
 
-  <!-- Slide-in side panel (inbox / todos flyouts) is a <hive-side-panel>
-       element (@hive/shared/side-panel.js) — the Panel singleton in
-       app.js creates + appends it to <body> lazily on first use, so
-       nothing needs to be pre-declared here. -->
+  <!-- Slide-in side panel. Singleton — JS swaps the title + body
+       and toggles `.open`. Shared shape with the dashboard's panel
+       (candidate for extraction into @hive/shared in a follow-up). -->
+  <div id="side-panel" class="side-panel" aria-hidden="true">
+    <div class="side-panel-backdrop" id="side-panel-backdrop"></div>
+    <aside class="side-panel-drawer" role="dialog" aria-modal="true"
+           aria-labelledby="side-panel-title">
+      <header class="side-panel-head">
+        <span class="side-panel-title" id="side-panel-title"></span>
+        <button type="button" class="side-panel-close" id="side-panel-close"
+                title="close (esc)">✕</button>
+      </header>
+      <div class="side-panel-body" id="side-panel-body"></div>
+    </aside>
+  </div>
 
   <!-- Single bundled entry. esbuild folds @hive/shared/terminal.js and
        the marked npm package into app.js. -->
diff --git a/frontend/packages/dashboard/src/call.js b/frontend/packages/dashboard/src/call.js
index 34902847..9e8df3a6 100644
--- a/frontend/packages/dashboard/src/call.js
+++ b/frontend/packages/dashboard/src/call.js
@@ -14,7 +14,7 @@
 // live-mutation paths call an injected `onCountsChanged` callback the entry
 // registers once via `initCall`.
 
-import { $, form, appendLinkified } from './common.js';
+import { $, form, Panel, appendLinkified } from './common.js';
 import { el } from '@hive/shared/dom.js';
 import { themedToast } from '@hive/shared/modal.js';
 import { epochSec, fmtAgo, fmtDuration } from './util.js';
diff --git a/frontend/packages/dashboard/src/common.css b/frontend/packages/dashboard/src/common.css
index d8746d73..8922df45 100644
--- a/frontend/packages/dashboard/src/common.css
+++ b/frontend/packages/dashboard/src/common.css
@@ -366,59 +366,134 @@ code {
 }
 
 /* ─── side panel ─────────────────────────────────────────────────
-   Long content (file previews, diffs, journald, applied config) opens in
-   a drawer that swipes in from the right — used by both /flow.html and
-   the dashboard. The drawer chrome itself (backdrop, drawer, resize
-   handle, header, title, close button) is now the shared
-   `<hive-side-panel>` element (@hive/shared/side-panel.js); what's left
-   here is the drag cursor-override escape hatch (has to be a global,
-   light-DOM rule — it reaches every element on the page during a drag,
-   not just the shared element's own shadow tree) and the styling for
-   the panel's own content types, which the shared element's shadow tree
-   can never reach (see @hive/shared/side-panel/hive-side-panel.css's
-   header comment). The `hive-side-panel .md …` rules below use the
-   element's own tag name as the selector root — no compatibility class
-   needed, the tag name already uniquely identifies the light-DOM
-   instance `common.js`'s `sidePanel` creates. */
+   Long content (file previews, diffs, journald, applied config)
+   opens in a drawer that swipes in from the right — used by both
+   /flow.html and the dashboard. */
+.side-panel {
+  position: fixed;
+  inset: 0;
+  z-index: 200;
+  pointer-events: none;
+}
+.side-panel-backdrop {
+  position: absolute;
+  inset: 0;
+  background: color-mix(in srgb, var(--crust) 55%, transparent);
+  opacity: 0;
+  transition: opacity 200ms ease;
+}
+.side-panel-drawer {
+  position: absolute;
+  top: 0;
+  right: 0;
+  bottom: 0;
+  width: min(42em, 95vw);
+  background: var(--bg-elev);
+  border-left: 1px solid var(--purple-dim);
+  display: flex;
+  flex-direction: column;
+  transform: translateX(100%);
+  transition: transform 220ms ease;
+  overflow: hidden;
+}
+.side-panel.open { pointer-events: auto; }
+.side-panel.open .side-panel-backdrop { opacity: 1; }
+.side-panel.open .side-panel-drawer { transform: translateX(0); }
+.side-panel-resize {
+  position: absolute;
+  left: 0;
+  top: 0;
+  bottom: 0;
+  width: 6px;
+  cursor: ew-resize;
+  opacity: 0;
+  transition: opacity 120ms;
+  background: var(--purple-dim);
+}
+.side-panel-resize:hover,
+body.side-panel-resizing .side-panel-resize {
+  opacity: 1;
+}
+body.side-panel-resizing .side-panel-resize {
+  background: var(--purple);
+}
 body.side-panel-resizing {
   user-select: none;
 }
 body.side-panel-resizing * { cursor: ew-resize !important; }
-hive-side-panel .md { color: var(--fg); line-height: 1.5; }
-hive-side-panel .md > :first-child { margin-top: 0; }
-hive-side-panel .md > :last-child { margin-bottom: 0; }
-hive-side-panel .md p { margin: 0.5em 0; }
-hive-side-panel .md h1,
-hive-side-panel .md h2,
-hive-side-panel .md h3,
-hive-side-panel .md h4 { color: var(--purple); margin: 0.9em 0 0.4em; }
-hive-side-panel .md code {
+.side-panel-head {
+  display: flex;
+  align-items: center;
+  gap: 0.6em;
+  padding: 0.6em 1em;
+  border-bottom: 1px solid var(--border);
+  flex: none;
+}
+.side-panel-title {
+  flex: 1;
+  font-size: 0.88em;
+  color: var(--muted);
+  letter-spacing: 0.04em;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+.side-panel-close {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  background: none;
+  border: 1px solid var(--border);
+  border-radius: 3px;
+  color: var(--muted);
+  font-size: 1em;
+  line-height: 1;
+  padding: 0.15em 0.4em;
+  cursor: pointer;
+  transition: border-color 0.15s ease, color 0.15s ease;
+}
+.side-panel-close:hover { border-color: var(--red); color: var(--red); }
+.side-panel-body {
+  flex: 1;
+  overflow-y: auto;
+  padding: 0.8em 1em;
+  font-size: 0.88em;
+}
+.side-panel-body .md { color: var(--fg); line-height: 1.5; }
+.side-panel-body .md > :first-child { margin-top: 0; }
+.side-panel-body .md > :last-child { margin-bottom: 0; }
+.side-panel-body .md p { margin: 0.5em 0; }
+.side-panel-body .md h1,
+.side-panel-body .md h2,
+.side-panel-body .md h3,
+.side-panel-body .md h4 { color: var(--purple); margin: 0.9em 0 0.4em; }
+.side-panel-body .md code {
   background: var(--bg);
   border: 1px solid var(--border);
   border-radius: 2px;
   padding: 0.1em 0.3em;
   font-size: 0.9em;
 }
-hive-side-panel .md pre {
+.side-panel-body .md pre {
   background: var(--crust);
   border: 1px solid var(--border);
   padding: 0.5em 0.7em;
   overflow-x: auto;
   margin: 0.5em 0;
 }
-hive-side-panel .md pre code { background: none; border: none; padding: 0; }
-hive-side-panel .md a { color: var(--cyan); }
-hive-side-panel .md ul,
-hive-side-panel .md ol { margin: 0.4em 0; padding-left: 1.5em; }
-hive-side-panel .md blockquote {
+.side-panel-body .md pre code { background: none; border: none; padding: 0; }
+.side-panel-body .md a { color: var(--cyan); }
+.side-panel-body .md ul,
+.side-panel-body .md ol { margin: 0.4em 0; padding-left: 1.5em; }
+.side-panel-body .md blockquote {
   border-left: 3px solid var(--purple-dim);
   padding-left: 0.8em;
   margin: 0.4em 0;
   color: var(--muted);
 }
-hive-side-panel .md table { border-collapse: collapse; margin: 0.5em 0; }
-hive-side-panel .md th,
-hive-side-panel .md td {
+.side-panel-body .md table { border-collapse: collapse; margin: 0.5em 0; }
+.side-panel-body .md th,
+.side-panel-body .md td {
   border: 1px solid var(--border);
   padding: 0.2em 0.5em;
 }
diff --git a/frontend/packages/dashboard/src/common.js b/frontend/packages/dashboard/src/common.js
index 6d34c7a7..44d6a56d 100644
--- a/frontend/packages/dashboard/src/common.js
+++ b/frontend/packages/dashboard/src/common.js
@@ -5,7 +5,6 @@
 
 import { linkify as termLinkify } from '@hive/shared/terminal.js';
 import { el } from '@hive/shared/dom.js';
-import '@hive/shared/side-panel.js'; // registers <hive-side-panel> — side-effect import
 import DOMPurify from 'dompurify';
 
 // ─── helpers ────────────────────────────────────────────────────────────
@@ -281,21 +280,141 @@ export function openBuildLogStream(id, pre, { onDone, onError } = {}) {
 // ─── side panel ─────────────────────────────────────────────────────────
 // Singleton drawer that swipes in from the right. Long content
 // (file previews, approval diffs, journald logs, applied config)
-// opens here via `sidePanel.open(title, node)` instead of expanding
+// opens here via `Panel.open(title, node)` instead of expanding
 // inline. Body is swapped on each open; closing just slides out so
 // the content stays visible through the transition.
-//
-// The instance is created once, eagerly, at module evaluation time — ES
-// modules run after the document is parsed (same timing `defer` scripts
-// get), so `document.body` already exists here. Exported directly (not
-// wrapped in a forwarding object) — callers use the element's own
-// `open`/`openNamed`/`refresh`/`close`/`currentOwner` methods, see
-// @hive/shared/side-panel.js for what they do. `common.css` reaches the
-// slotted content via a plain `hive-side-panel .md …` tag-name selector
-// (no compatibility class needed — the element's own tag name already
-// uniquely identifies it in the light DOM).
-export const sidePanel = document.createElement('hive-side-panel');
-document.body.append(sidePanel);
+export const Panel = (() => {
+  let root = null;
+  let titleEl = null;
+  let bodyEl = null;
+  let drawer = null;
+  /** Owner key set by `openNamed` (e.g. 'inbox'). `refresh(name, …)`
+   *  is a no-op when the current owner doesn't match, so live
+   *  updates can re-render an open view without grabbing focus
+   *  from a closed one (or from an unrelated open view like a
+   *  diff drill-in). Untyped calls via `open(title, content)`
+   *  clear the owner — the legacy file-preview/diff/log paths
+   *  don't participate in named-refresh semantics. */
+  let owner = null;
+  function ensure() {
+    if (!root) {
+      root = $('side-panel');
+      titleEl = $('side-panel-title');
+      bodyEl = $('side-panel-body');
+      drawer = root && root.querySelector('.side-panel-drawer');
+    }
+    return root != null;
+  }
+  function open(title, content) {
+    if (!ensure()) return;
+    owner = null;
+    titleEl.textContent = title;
+    bodyEl.replaceChildren(...(content ? [content] : []));
+    root.classList.add('open');
+    root.setAttribute('aria-hidden', 'false');
+  }
+  function openNamed(name, title, content) {
+    open(title, content);
+    owner = name;
+  }
+  function refresh(name, title, content) {
+    if (!ensure()) return;
+    if (owner !== name) return;
+    titleEl.textContent = title;
+    bodyEl.replaceChildren(...(content ? [content] : []));
+  }
+  function close() {
+    if (!ensure()) return;
+    owner = null;
+    root.classList.remove('open');
+    root.setAttribute('aria-hidden', 'true');
+  }
+  // Drag-to-resize the drawer's width. See docs/web-ui.md::Side panel
+  // for the hit-strip + pointer-capture + localStorage persistence
+  // model; CSS clamps the stored value to min 320px / max 96vw and
+  // out-of-range stored values are dropped silently.
+  const WIDTH_KEY = 'hyperhive:side-panel-width';
+  const WIDTH_MIN = 320;
+  function clampWidth(w) {
+    // Use document.documentElement.clientWidth rather than window.innerWidth:
+    // clientWidth gives the actual CSS layout viewport width and is not
+    // altered by Firefox's Fingerprinting Protection (which rounds
+    // window.innerWidth/outerWidth to the nearest 200px).
+    const max = Math.floor(document.documentElement.clientWidth * 0.96);
+    return Math.max(WIDTH_MIN, Math.min(max, w));
+  }
+  function applyStoredWidth() {
+    if (!drawer) return;
+    const raw = (() => {
+      try { return localStorage.getItem(WIDTH_KEY); }
+      catch { return null; }
+    })();
+    if (!raw) return;
+    const parsed = parseInt(raw, 10);
+    if (!Number.isFinite(parsed) || parsed <= 0) return;
+    drawer.style.setProperty('--side-panel-w', clampWidth(parsed) + 'px');
+  }
+  function bindResize() {
+    if (!drawer) return;
+    const handle = document.createElement('div');
+    handle.className = 'side-panel-resize';
+    handle.setAttribute('role', 'separator');
+    handle.setAttribute('aria-orientation', 'vertical');
+    handle.setAttribute('aria-label', 'drag to resize side panel');
+    handle.title = 'drag to resize';
+    drawer.prepend(handle);
+    let dragging = false;
+    handle.addEventListener('pointerdown', (e) => {
+      e.preventDefault();
+      dragging = true;
+      document.body.classList.add('side-panel-resizing');
+      // Capture so we keep getting pointermove even when the cursor
+      // outpaces the handle band (drag-fast-then-pause loses the
+      // handle's :hover state otherwise).
+      try { handle.setPointerCapture(e.pointerId); } catch { /* legacy */ }
+    });
+    document.addEventListener('pointermove', (e) => {
+      if (!dragging) return;
+      // Drawer is anchored to the right edge — width = viewport - pointer X.
+      const w = clampWidth(document.documentElement.clientWidth - e.clientX);
+      drawer.style.setProperty('--side-panel-w', w + 'px');
+    });
+    function stopDrag() {
+      if (!dragging) return;
+      dragging = false;
+      document.body.classList.remove('side-panel-resizing');
+      // Persist the final width. Read the actual rendered width
+      // rather than re-deriving so the stored value matches what
+      // the operator saw at mouseup.
+      const w = drawer.getBoundingClientRect().width;
+      try { localStorage.setItem(WIDTH_KEY, String(Math.round(w))); }
+      catch { /* localStorage unavailable — width is session-only */ }
+    }
+    document.addEventListener('pointerup', stopDrag);
+    document.addEventListener('pointercancel', stopDrag);
+    // Re-clamp on viewport resize so a persisted width that exceeds
+    // 96vw doesn't push the drawer off-screen after a window shrink.
+    window.addEventListener('resize', () => {
+      if (dragging) return;
+      const cur = drawer.getBoundingClientRect().width;
+      const clamped = clampWidth(cur);
+      if (clamped !== Math.round(cur)) {
+        drawer.style.setProperty('--side-panel-w', clamped + 'px');
+      }
+    });
+  }
+  function bind() {
+    if (!ensure()) return;
+    $('side-panel-close').addEventListener('click', close);
+    $('side-panel-backdrop').addEventListener('click', close);
+    document.addEventListener('keydown', (e) => {
+      if (e.key === 'Escape' && root.classList.contains('open')) close();
+    });
+    applyStoredWidth();
+    bindResize();
+  }
+  return { open, openNamed, refresh, close, bind };
+})();
 
 // ─── path linkification ─────────────────────────────────────────────────
 // Agents constantly drop pointer strings into messages + question
@@ -386,14 +505,14 @@ async function openFilePanel(path) {
         '(could not load image — it may be missing or over the preview size cap)'));
     });
     img.src = '/api/state-file?path=' + encodeURIComponent(path);
-    sidePanel.open('↳ ' + path, img);
+    Panel.open('↳ ' + path, img);
     return;
   }
   const isMd = /\.(md|markdown)$/i.test(path);
   const isSvg = /\.svg$/i.test(path);
   const view = el('div');
   view.textContent = '(fetching…)';
-  sidePanel.open('↳ ' + path, view);
+  Panel.open('↳ ' + path, view);
   try {
     const text = await fetchStateFile(path);
     if (isSvg) {
diff --git a/frontend/packages/dashboard/src/dashboard.html b/frontend/packages/dashboard/src/dashboard.html
index e3f3007d..a15a94e3 100644
--- a/frontend/packages/dashboard/src/dashboard.html
+++ b/frontend/packages/dashboard/src/dashboard.html
@@ -234,11 +234,23 @@
     <p>▲△▲ <a href="https://forge.darkest.space/hyperhive/hyperhive">hyperhive</a> ▲△▲ hive-c0re on this host ▲△▲</p>
   </footer>
 
-  <!-- Slide-in detail panel (clicked file previews, approval diffs,
-       journald logs, applied config) is a <hive-side-panel> element
-       (@hive/shared/side-panel.js) — the Panel singleton in common.js
-       creates + appends it to <body> lazily on first use, so nothing
-       needs to be pre-declared here. -->
+  <!-- Slide-in detail panel. Long content (clicked file previews,
+       approval diffs, journald logs, applied config) opens here
+       instead of expanding inline. Singleton — JS swaps the title +
+       body and toggles `.open`. Lives outside the tab panes so it
+       overlays any active tab. -->
+  <div id="side-panel" class="side-panel" aria-hidden="true">
+    <div class="side-panel-backdrop" id="side-panel-backdrop"></div>
+    <aside class="side-panel-drawer" role="dialog" aria-modal="true"
+           aria-labelledby="side-panel-title">
+      <header class="side-panel-head">
+        <span class="side-panel-title" id="side-panel-title"></span>
+        <button type="button" class="side-panel-close" id="side-panel-close"
+                title="close (esc)">✕</button>
+      </header>
+      <div class="side-panel-body" id="side-panel-body"></div>
+    </aside>
+  </div>
 
   <!-- Selection action bar. Sticky-bottom strip that slides into
        view when one or more agent cards is selected (click the icon
diff --git a/frontend/packages/dashboard/src/tabs.js b/frontend/packages/dashboard/src/tabs.js
index 9b2af49c..7989fc1e 100644
--- a/frontend/packages/dashboard/src/tabs.js
+++ b/frontend/packages/dashboard/src/tabs.js
@@ -14,7 +14,7 @@
 import { marked } from 'marked';
 import {
   $,
-  NOTIF,
+  Panel, NOTIF,
   openStream, renderServerWarnings,
 } from './common.js';
 import { el } from '@hive/shared/dom.js';
@@ -276,9 +276,8 @@ window.marked = marked;
   // NOTIF.bind() (the enable/mute/unmute toggle UI) moved to /settings.html
   // with the S3TT1NGS page. The dashboard keeps NOTIF.show() for approval/
   // question notifications — it reads the browser permission + localStorage
-  // mute flag the settings page sets, so no bind() is needed here. The
-  // side panel (<hive-side-panel>) wires its own internals in
-  // connectedCallback — no bind() step needed either.
+  // mute flag the settings page sets, so no bind() is needed here.
+  Panel.bind();
 
   // ─── live updates: dashboard event stream ──────────────────────────────
   // The dashboard subscribes to /dashboard/stream for live mutation
diff --git a/frontend/packages/shared/package.json b/frontend/packages/shared/package.json
index 590794a2..3bdbeeb0 100644
--- a/frontend/packages/shared/package.json
+++ b/frontend/packages/shared/package.json
@@ -19,8 +19,7 @@
     "./dom.js": "./src/dom.js",
     "./modal.js": "./src/modal.js",
     "./shadow-css.js": "./src/shadow-css.js",
-    "./hive-menu.js": "./src/hive-menu/hive-menu.js",
-    "./side-panel.js": "./src/side-panel/hive-side-panel.js"
+    "./hive-menu.js": "./src/hive-menu/hive-menu.js"
   },
   "files": [
     "src/"
diff --git a/frontend/packages/shared/src/side-panel/hive-side-panel.css b/frontend/packages/shared/src/side-panel/hive-side-panel.css
deleted file mode 100644
index 51048616..00000000
--- a/frontend/packages/shared/src/side-panel/hive-side-panel.css
+++ /dev/null
@@ -1,111 +0,0 @@
-/* hive-side-panel.css — scoped stylesheet for the generic <hive-side-panel>
-   shadow-DOM custom element (hive-side-panel.js). Loaded as raw text at
-   build time (esbuild's `text` loader) and appended as a <style> element
-   inside the shadow root — see @hive/shared/shadow-css.js's header comment
-   for why a plain <style> tag and not adoptedStyleSheets.
-
-   Every rule here styles shadow-owned chrome this element builds itself
-   (backdrop, drawer, resize handle, header, title, close button) — none of
-   it is slotted, so this file needs zero `::slotted()`. The one slotted
-   node (the caller's opaque content, passed to open()/openNamed()/
-   refresh()) is intentionally un-styled from in here: each package's own
-   content-type-specific rules (`hive-side-panel .md` in the dashboard,
-   `hive-side-panel .agent-inbox` in the agent UI) live in that package's
-   own global stylesheet and reach the slotted content via the element's
-   own tag name as the selector root — no compatibility class needed,
-   same architecture floor as `<hive-menu>`'s item-row styling, not a
-   scope choice.
-
-   `:host(.open)`/`:host(.resizing)` respond to the two state classes the
-   JS toggles on the host itself (`open`, and `resizing` during a drag) —
-   the shadow-scoped counterparts of the page-global `body.side-panel-
-   resizing` cursor-override class, which stays in each package's own
-   stylesheet since it has to reach light-DOM elements outside this
-   element entirely (see hive-side-panel.js's module header). */
-
-:host {
-  position: fixed;
-  inset: 0;
-  z-index: 200;
-  pointer-events: none;
-}
-.side-panel-backdrop {
-  position: absolute;
-  inset: 0;
-  background: color-mix(in srgb, var(--crust) 55%, transparent);
-  opacity: 0;
-  transition: opacity 200ms ease;
-}
-.side-panel-drawer {
-  position: absolute;
-  top: 0;
-  right: 0;
-  bottom: 0;
-  width: var(--side-panel-w, min(42em, 95vw));
-  background: var(--bg-elev);
-  border-left: 1px solid var(--purple-dim);
-  display: flex;
-  flex-direction: column;
-  transform: translateX(100%);
-  transition: transform 220ms ease;
-  overflow: hidden;
-}
-:host(.open) { pointer-events: auto; }
-:host(.open) .side-panel-backdrop { opacity: 1; }
-:host(.open) .side-panel-drawer { transform: translateX(0); }
-.side-panel-resize {
-  position: absolute;
-  left: 0;
-  top: 0;
-  bottom: 0;
-  width: 6px;
-  cursor: ew-resize;
-  opacity: 0;
-  transition: opacity 120ms;
-  background: var(--purple-dim);
-}
-.side-panel-resize:hover,
-:host(.resizing) .side-panel-resize {
-  opacity: 1;
-}
-:host(.resizing) .side-panel-resize {
-  background: var(--purple);
-}
-.side-panel-head {
-  display: flex;
-  align-items: center;
-  gap: 0.6em;
-  padding: 0.6em 1em;
-  border-bottom: 1px solid var(--border);
-  flex: none;
-}
-.side-panel-title {
-  flex: 1;
-  font-size: 0.88em;
-  color: var(--muted);
-  letter-spacing: 0.04em;
-  overflow: hidden;
-  text-overflow: ellipsis;
-  white-space: nowrap;
-}
-.side-panel-close {
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  background: none;
-  border: 1px solid var(--border);
-  border-radius: 3px;
-  color: var(--muted);
-  font-size: 1em;
-  line-height: 1;
-  padding: 0.15em 0.4em;
-  cursor: pointer;
-  transition: border-color 0.15s ease, color 0.15s ease;
-}
-.side-panel-close:hover { border-color: var(--red); color: var(--red); }
-.side-panel-body {
-  flex: 1;
-  overflow-y: auto;
-  padding: 0.8em 1em;
-  font-size: 0.88em;
-}
diff --git a/frontend/packages/shared/src/side-panel/hive-side-panel.js b/frontend/packages/shared/src/side-panel/hive-side-panel.js
deleted file mode 100644
index 01306719..00000000
--- a/frontend/packages/shared/src/side-panel/hive-side-panel.js
+++ /dev/null
@@ -1,183 +0,0 @@
-// hive-side-panel.js — <hive-side-panel>, the generic slide-in drawer
-// shadow-DOM custom element behind the dashboard's and the per-agent UI's
-// side panel (file previews, diffs, logs, inbox/todo lists — anything too
-// long to expand inline). One singleton instance per page, created once,
-// eagerly, by each package's own module (dashboard/src/common.js's
-// `sidePanel`, agent/src/app.js's `sidePanel`) and used directly — no
-// wrapper object, no per-call lazy-init guard.
-//
-// Builds all structural chrome itself in `connectedCallback` (backdrop,
-// drawer, resize handle, header, title, close button) — shadow-owned,
-// zero `::slotted()` needed. Only the panel *content* is opaque
-// caller-built DOM, appended as a light-DOM child and picked up by the
-// shadow tree's single default `<slot>`, exactly like `<hive-menu>`'s
-// `content` (see that file's header for why). Each package's own global
-// stylesheet reaches that content via the element's own tag name as the
-// selector root (`hive-side-panel .md`, `hive-side-panel .agent-inbox`)
-// — no compatibility class needed.
-//
-// Public API is instance methods: `open(title, content)`,
-// `openNamed(name, title, content)`, `refresh(name, title, content)`,
-// `close()`, `currentOwner()`. `open` is exactly `openNamed(null, title,
-// content)` — untyped opens clear the owner, matching the dashboard's
-// original semantics.
-//
-// Drag-to-resize + localStorage width persistence is ported from the
-// dashboard's original `Panel` (the only one of the two originals that
-// had it) — making it available to every consumer (the agent UI didn't
-// have it before) is a deliberate behavior widening, not incidental.
-
-import { el } from '../dom.js';
-import { attachShadowCss } from '../shadow-css.js';
-import sidePanelCss from './hive-side-panel.css';
-
-// See docs/web-ui.md::Side panel for the hit-strip + pointer-capture +
-// localStorage persistence model; CSS clamps the stored value to min
-// 320px / max 96vw and out-of-range stored values are dropped silently.
-// Shared by both packages deliberately — see module header.
-const WIDTH_KEY = 'hyperhive:side-panel-width';
-const WIDTH_MIN = 320;
-
-class HiveSidePanel extends HTMLElement {
-  connectedCallback() {
-    const root = attachShadowCss(this, sidePanelCss);
-    this.setAttribute('aria-hidden', 'true');
-    this._owner = null;
-
-    this._titleEl = el('span', { class: 'side-panel-title', id: 'side-panel-title' });
-    this._closeBtn = el('button', {
-      type: 'button', class: 'side-panel-close', title: 'close (esc)',
-    }, '✕');
-    const head = el('header', { class: 'side-panel-head' }, this._titleEl, this._closeBtn);
-
-    this._resizeHandle = el('div', {
-      class: 'side-panel-resize',
-      role: 'separator',
-      'aria-orientation': 'vertical',
-      'aria-label': 'drag to resize side panel',
-      title: 'drag to resize',
-    });
-
-    this._bodyEl = el('div', { class: 'side-panel-body' }, el('slot'));
-
-    this._drawer = el('aside', {
-      class: 'side-panel-drawer',
-      role: 'dialog',
-      'aria-modal': 'true',
-      'aria-labelledby': 'side-panel-title',
-    }, this._resizeHandle, head, this._bodyEl);
-
-    this._backdrop = el('div', { class: 'side-panel-backdrop' });
-
-    root.append(this._backdrop, this._drawer);
-
-    this._closeBtn.addEventListener('click', () => this.close());
-    this._backdrop.addEventListener('click', () => this.close());
-    document.addEventListener('keydown', (e) => {
-      if (e.key === 'Escape' && this.classList.contains('open')) this.close();
-    });
-
-    this._applyStoredWidth();
-    this._bindResize();
-  }
-
-  open(title, content) {
-    this.openNamed(null, title, content);
-  }
-
-  openNamed(name, title, content) {
-    this._owner = name;
-    this._titleEl.textContent = title;
-    this.replaceChildren(...(content ? [content] : []));
-    this.classList.add('open');
-    this.setAttribute('aria-hidden', 'false');
-  }
-
-  refresh(name, title, content) {
-    if (this._owner !== name) return;
-    this._titleEl.textContent = title;
-    this.replaceChildren(...(content ? [content] : []));
-  }
-
-  close() {
-    this._owner = null;
-    this.classList.remove('open');
-    this.setAttribute('aria-hidden', 'true');
-  }
-
-  currentOwner() {
-    return this._owner;
-  }
-
-  _clampWidth(w) {
-    // Use document.documentElement.clientWidth rather than window.innerWidth:
-    // clientWidth gives the actual CSS layout viewport width and is not
-    // altered by Firefox's Fingerprinting Protection (which rounds
-    // window.innerWidth/outerWidth to the nearest 200px).
-    const max = Math.floor(document.documentElement.clientWidth * 0.96);
-    return Math.max(WIDTH_MIN, Math.min(max, w));
-  }
-
-  _applyStoredWidth() {
-    const raw = (() => {
-      try { return localStorage.getItem(WIDTH_KEY); }
-      catch { return null; }
-    })();
-    if (!raw) return;
-    const parsed = parseInt(raw, 10);
-    if (!Number.isFinite(parsed) || parsed <= 0) return;
-    this._drawer.style.setProperty('--side-panel-w', this._clampWidth(parsed) + 'px');
-  }
-
-  _bindResize() {
-    const handle = this._resizeHandle;
-    const drawer = this._drawer;
-    let dragging = false;
-    handle.addEventListener('pointerdown', (e) => {
-      e.preventDefault();
-      dragging = true;
-      document.body.classList.add('side-panel-resizing');
-      // Shadow-scoped counterpart of the global `body.side-panel-resizing`
-      // class below — the resize handle's own hover/drag appearance lives
-      // inside this element's shadow tree, which the global class (a
-      // light-DOM-only escape hatch for the page-wide cursor override)
-      // can't reach.
-      this.classList.add('resizing');
-      // Capture so we keep getting pointermove even when the cursor
-      // outpaces the handle band (drag-fast-then-pause loses the
-      // handle's :hover state otherwise).
-      try { handle.setPointerCapture(e.pointerId); } catch { /* legacy */ }
-    });
-    document.addEventListener('pointermove', (e) => {
-      if (!dragging) return;
-      // Drawer is anchored to the right edge — width = viewport - pointer X.
-      const w = this._clampWidth(document.documentElement.clientWidth - e.clientX);
-      drawer.style.setProperty('--side-panel-w', w + 'px');
-    });
-    const stopDrag = () => {
-      if (!dragging) return;
-      dragging = false;
-      document.body.classList.remove('side-panel-resizing');
-      this.classList.remove('resizing');
-      // Persist the final width. Read the actual rendered width
-      // rather than re-deriving so the stored value matches what
-      // the operator saw at mouseup.
-      const w = drawer.getBoundingClientRect().width;
-      try { localStorage.setItem(WIDTH_KEY, String(Math.round(w))); }
-      catch { /* localStorage unavailable — width is session-only */ }
-    };
-    document.addEventListener('pointerup', stopDrag);
-    document.addEventListener('pointercancel', stopDrag);
-    // Re-clamp on viewport resize so a persisted width that exceeds
-    // 96vw doesn't push the drawer off-screen after a window shrink.
-    window.addEventListener('resize', () => {
-      if (dragging) return;
-      const cur = drawer.getBoundingClientRect().width;
-      const clamped = this._clampWidth(cur);
-      if (clamped !== Math.round(cur)) {
-        drawer.style.setProperty('--side-panel-w', clamped + 'px');
-      }
-    });
-  }
-}
-customElements.define('hive-side-panel', HiveSidePanel);