Storyline: split the chapter page, dock the notes at the bottom

The chapter page now fills the viewport as two horizontal panes: the
chapter scrolls in the top ~2/3, the notes sit in a fixed dock in the
bottom ~1/3, always visible while you read. Drag the divider to change
the ratio, click the "Chapter notes" header to collapse the dock to a
bar; both the height and the collapsed state persist in localStorage.

- base.html.twig: add a {% block body_class %} hook on <body>.
- chapter.html.twig sets body class "storyline-chapter-page"; the split
  layout CSS is scoped to it and falls back to normal stacked flow under
  768px wide or 560px tall.
- app.js publishes the navbar height as --app-nav-h so the split can size
  itself to viewport-minus-navbar even when the navbar wraps.
- new chapter_notes Stimulus controller: drag-resize + collapse + persist.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

assets/app.js

@@ -145,3 +145,16 @@ document.addEventListener('shown.bs.collapse', (e) => rememberStatblock(e.target
 document.addEventListener('hidden.bs.collapse', (e) => rememberStatblock(e.target, false));
 document.addEventListener('DOMContentLoaded', restoreStatblocks);
 document.addEventListener('turbo:load', restoreStatblocks);
+
+// --- Publish the navbar height as --app-nav-h -------------------------
+// The storyline chapter page sizes its split view to the viewport minus the
+// navbar; the navbar grows when it wraps, so measure it rather than guess.
+function publishNavHeight() {
+    const nav = document.querySelector('.navbar');
+    const h = nav ? Math.round(nav.getBoundingClientRect().height) : 56;
+    document.documentElement.style.setProperty('--app-nav-h', `${h}px`);
+}
+
+document.addEventListener('DOMContentLoaded', publishNavHeight);
+document.addEventListener('turbo:load', publishNavHeight);
+window.addEventListener('resize', publishNavHeight);

assets/controllers/chapter_notes_controller.js

@@ -0,0 +1,113 @@
+import { Controller } from '@hotwired/stimulus';
+
+/*
+ * The docked "Chapter notes" panel on a storyline chapter page.
+ *
+ *   <div class="storyline-split" data-controller="chapter-notes">
+ *     ...chapter...
+ *     <div class="storyline-notes-resize" data-chapter-notes-target="handle"
+ *          data-action="pointerdown->chapter-notes#startResize"></div>
+ *     <section class="storyline-notes-dock" data-chapter-notes-target="dock">
+ *       <button data-action="chapter-notes#toggle" data-chapter-notes-target="toggle">…</button>
+ *       ...
+ *     </section>
+ *   </div>
+ *
+ * Drag the handle to resize; click the header to collapse. Both the pixel
+ * height and the collapsed flag persist per browser (localStorage).
+ */
+const H_KEY = 'dmtools.chapterNotesHeight';
+const C_KEY = 'dmtools.chapterNotesCollapsed';
+const MIN_PX = 44;
+const MIN_TOP_PX = 140;
+
+export default class extends Controller {
+    static targets = ['dock', 'handle', 'toggle'];
+
+    connect() {
+        this.onMove = this.onMove.bind(this);
+        this.endResize = this.endResize.bind(this);
+
+        let stored = null;
+        try {
+            stored = localStorage.getItem(H_KEY);
+        } catch (e) {
+            /* private mode */
+        }
+        if (stored) {
+            this.element.style.setProperty('--notes-h', `${this.clamp(parseInt(stored, 10))}px`);
+        }
+
+        let collapsed = false;
+        try {
+            collapsed = localStorage.getItem(C_KEY) === '1';
+        } catch (e) {
+            /* ignore */
+        }
+        this.setCollapsed(collapsed);
+    }
+
+    disconnect() {
+        this.endResize();
+    }
+
+    toggle() {
+        this.setCollapsed(!this.dockTarget.classList.contains('is-collapsed'));
+    }
+
+    setCollapsed(on) {
+        this.dockTarget.classList.toggle('is-collapsed', on);
+        if (this.hasToggleTarget) {
+            this.toggleTarget.setAttribute('aria-expanded', on ? 'false' : 'true');
+        }
+        try {
+            localStorage.setItem(C_KEY, on ? '1' : '0');
+        } catch (e) {
+            /* ignore */
+        }
+    }
+
+    startResize(event) {
+        if (this.dockTarget.classList.contains('is-collapsed')) return;
+        event.preventDefault();
+        this.resizing = true;
+        this.handleTarget.setPointerCapture?.(event.pointerId);
+        document.body.style.userSelect = 'none';
+        document.body.style.cursor = 'row-resize';
+        window.addEventListener('pointermove', this.onMove);
+        window.addEventListener('pointerup', this.endResize);
+        window.addEventListener('pointercancel', this.endResize);
+    }
+
+    onMove(event) {
+        if (!this.resizing) return;
+        const rect = this.element.getBoundingClientRect();
+        const px = this.clamp(rect.bottom - event.clientY);
+        this.element.style.setProperty('--notes-h', `${px}px`);
+    }
+
+    endResize() {
+        window.removeEventListener('pointermove', this.onMove);
+        window.removeEventListener('pointerup', this.endResize);
+        window.removeEventListener('pointercancel', this.endResize);
+        if (!this.resizing) return;
+        this.resizing = false;
+        document.body.style.userSelect = '';
+        document.body.style.cursor = '';
+
+        const current = this.element.style.getPropertyValue('--notes-h');
+        if (current.endsWith('px')) {
+            try {
+                localStorage.setItem(H_KEY, parseInt(current, 10));
+            } catch (e) {
+                /* ignore */
+            }
+        }
+    }
+
+    clamp(px) {
+        if (!Number.isFinite(px)) return MIN_PX;
+        const max = Math.max(MIN_PX, this.element.getBoundingClientRect().height - MIN_TOP_PX);
+        return Math.min(Math.max(px, MIN_PX), max);
+    }
+}

assets/styles/app.css

@@ -192,7 +192,7 @@ table.dataTable {
 /* --- Storyline: chapter layout + table of contents ------------------- */
 .storyline-toc {
     position: sticky;
-    top: 1.5rem;
+    top: 0.25rem;
     font-size: 0.9375rem;
 }
 .storyline-toc-link {
@@ -429,22 +429,126 @@ table.dataTable {
 }
 .storyline-pager-title { font-weight: 600; }
 
-/* Chapter notes: collapsible card above the chapter body */
+/* --- Storyline chapter page: split view (content above, notes docked) --- */
-.storyline-notes > summary {
+/* On wide/tall screens the chapter page fills the viewport: the top pane
-    cursor: pointer;
+   scrolls the chapter, the bottom pane is a fixed-height notes dock. Falls
-    list-style: none;
+   back to normal document flow on small screens (see media query below). */
+.storyline-chapter-page { overflow: hidden; }
+.storyline-chapter-page main.app-main {
+    min-height: 0;
+    padding: 0;
+    height: calc(100vh - var(--app-nav-h, 3.5rem));
+    height: calc(100dvh - var(--app-nav-h, 3.5rem));
+}
+.storyline-chapter-page main.app-main > .container {
+    height: 100%;
+    display: flex;
+    flex-direction: column;
+    padding-top: 0.75rem;
+}
+.storyline-split {
+    flex: 1 1 auto;
+    min-height: 0;
+    display: flex;
+    flex-direction: column;
+    /* --notes-h is set by the resize handle; default is one third */
+    --notes-h: 33%;
+}
+.storyline-split-main {
+    flex: 1 1 auto;
+    min-height: 0;
+    overflow-y: auto;
+    overflow-x: hidden;
+    padding-bottom: 1.5rem;
+}
+.storyline-notes-resize {
+    flex: 0 0 auto;
+    height: 10px;
+    margin: 0 -0.5rem;
+    cursor: row-resize;
+    background:
+        linear-gradient(var(--bs-border-color), var(--bs-border-color)) center/2.5rem 2px no-repeat;
+    border-top: 1px solid var(--bs-border-color);
+}
+.storyline-notes-resize:hover { background-color: var(--bs-tertiary-bg); }
+.storyline-notes-dock {
+    flex: 0 0 var(--notes-h);
+    min-height: 2.75rem;
+    display: flex;
+    flex-direction: column;
+    background: var(--bs-body-bg);
+    border-top: 1px solid var(--bs-border-color);
+}
+.storyline-notes-bar {
+    flex: 0 0 auto;
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    gap: 1rem;
+    padding: 0.4rem 0.1rem;
+}
+.storyline-notes-toggle {
+    border: 0;
+    background: none;
+    padding: 0.15rem 0.25rem;
     font-weight: 600;
+    color: var(--bs-body-color);
+    display: inline-flex;
+    align-items: center;
+    gap: 0.4rem;
+    cursor: pointer;
 }
-.storyline-notes > summary::-webkit-details-marker { display: none; }
+.storyline-notes-caret { transition: transform 0.15s ease; display: inline-block; }
-.storyline-notes > summary::before {
+.storyline-notes-dock.is-collapsed { flex: 0 0 auto !important; }
-    content: "\25B8";              /* right-pointing triangle */
+.storyline-notes-dock.is-collapsed .storyline-notes-body { display: none; }
-    display: inline-block;
+.storyline-notes-dock.is-collapsed .storyline-notes-caret { transform: rotate(-90deg); }
-    margin-right: 0.5rem;
+.storyline-notes-resize:has(+ .storyline-notes-dock.is-collapsed) { display: none; }
-    color: var(--bs-secondary-color);
+
-    transition: transform 0.15s ease;
+.storyline-notes-body {
+    flex: 1 1 auto;
+    min-height: 0;
+    padding-bottom: 0.5rem;
+}
+.storyline-notes-form {
+    height: 100%;
+    display: flex;
+    flex-direction: column;
+    gap: 0.5rem;
+}
+.storyline-notes-text {
+    flex: 1 1 auto;
+    min-height: 0;
+    resize: none;
+    font-size: 0.95rem;
+    line-height: 1.55;
+}
+.storyline-notes-actions {
+    flex: 0 0 auto;
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+}
+
+/* Small or short screens: no fixed split, just stack notes under the chapter. */
+@media (max-width: 767.98px), (max-height: 560px) {
+    .storyline-chapter-page { overflow: visible; }
+    .storyline-chapter-page main.app-main {
+        height: auto;
+        padding-top: 1.5rem;
+        padding-bottom: 3rem;
+    }
+    .storyline-chapter-page main.app-main > .container { display: block; height: auto; }
+    .storyline-split { display: block; }
+    .storyline-split-main { overflow: visible; }
+    .storyline-notes-resize { display: none; }
+    .storyline-notes-dock {
+        flex-basis: auto;
+        margin-top: 1.5rem;
+        border-top-width: 2px;
+        padding-top: 0.5rem;
+    }
+    .storyline-notes-text { min-height: 9rem; }
 }
-.storyline-notes[open] > summary::before { transform: rotate(90deg); }
-.storyline-notes textarea { font-size: 0.95rem; line-height: 1.6; }
 
 /* Chapter list: kicker line above each title */
 .storyline-chapter-kicker {

templates/base.html.twig

@@ -12,7 +12,7 @@
             {% block importmap %}{{ importmap('app') }}{% endblock %}
         {% endblock %}
     </head>
-    <body class="d-flex flex-column">
+    <body class="d-flex flex-column {% block body_class %}{% endblock %}">
         {% block navbar %}
         <nav class="navbar navbar-expand-lg bg-body-tertiary border-bottom">
             <div class="container">

templates/storyline/chapter.html.twig

@@ -2,7 +2,11 @@
 
 {% block title %}{{ chapter.title }} · Storyline · dmtools{% endblock %}
 
+{% block body_class %}storyline-chapter-page{% endblock %}
+
 {% block body %}
+    <div class="storyline-split" data-controller="chapter-notes">
+        <div class="storyline-split-main">
             <div class="row g-4 storyline-layout">
                 <nav class="col-lg-3 order-lg-2">
                     <div class="storyline-toc">
@@ -22,24 +26,6 @@
                 </nav>
 
                 <div class="col-lg-9 order-lg-1">
-            <details class="card shadow-sm mb-4 storyline-notes" open>
-                <summary class="card-header d-flex justify-content-between align-items-center">
-                    <span>📝 Chapter notes</span>
-                    {% if note.updatedAt %}
-                        <span class="text-body-secondary small fw-normal">saved {{ note.updatedAt|date('Y-m-d H:i') }}</span>
-                    {% endif %}
-                </summary>
-                <div class="card-body">
-                    <p class="text-body-secondary small mb-2">
-                        Your running log for this chapter — what actually happened at the table.
-                    </p>
-                    {{ form_start(form) }}
-                    {{ form_row(form.notes) }}
-                    <button class="btn btn-primary mt-2">Save notes</button>
-                    {{ form_end(form) }}
-                </div>
-            </details>
-
                     <article class="storyline-doc">
                         <header class="storyline-doc-head">
                             <div class="storyline-eyebrow">Storyline &middot; {{ chapter.eyebrow }}</div>
@@ -66,4 +52,32 @@
                     </nav>
                 </div>
             </div>
+        </div>
+
+        <div class="storyline-notes-resize" data-chapter-notes-target="handle"
+             data-action="pointerdown->chapter-notes#startResize" role="separator"
+             aria-label="Resize notes panel" title="Drag to resize"></div>
+
+        <section class="storyline-notes-dock" data-chapter-notes-target="dock">
+            <div class="storyline-notes-bar">
+                <button type="button" class="storyline-notes-toggle" data-action="chapter-notes#toggle"
+                        data-chapter-notes-target="toggle" aria-expanded="true">
+                    <span class="storyline-notes-caret">&#9662;</span> Chapter notes
+                </button>
+                {% if note.updatedAt %}
+                    <span class="text-body-secondary small">saved {{ note.updatedAt|date('Y-m-d H:i') }}</span>
+                {% endif %}
+            </div>
+            <div class="storyline-notes-body">
+                {{ form_start(form, {attr: {class: 'storyline-notes-form'}}) }}
+                    {{ form_errors(form.notes) }}
+                    {{ form_widget(form.notes, {attr: {class: 'form-control storyline-notes-text'}}) }}
+                    <div class="storyline-notes-actions">
+                        <button class="btn btn-primary btn-sm">Save notes</button>
+                        <span class="text-body-secondary small">This chapter only. Saved to the server.</span>
+                    </div>
+                {{ form_end(form) }}
+            </div>
+        </section>
+    </div>
 {% endblock %}