diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0003f6e..a924ca9 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,10 @@
 All notable changes to Void 2.0 are documented here.
 Format: [Keep a Changelog](https://keepachangelog.com).
 
+## 2.0.0-alpha.13 — Finer Sacred Valley tile scaling
+- Cards now sit on a 12-column grid with a per-card width **−/+ stepper** (span 1–12) in edit mode, replacing the coarse S/M/L. "Small" defaults to 1/6 width (half its previous size) so clock/weather aren't oversized.
+- Layout `sizes` now store an integer column span (legacy 's'/'m'/'l' still accepted).
+
 ## 2.0.0-alpha.12 — Editable Sacred Valley layout
 - "Edit layout" mode on the dashboard: per-card **resize** (S/M/L column span), **show/hide** (with a hidden-cards tray to re-add), clearer **drag-to-reorder** via a dedicated grip handle, and a **Reset** to defaults.
 - All changes persist through the existing `/api/dashboard/layout` (order/sizes/hidden) — no backend changes.
diff --git a/lib/api/routes/dashboard.js b/lib/api/routes/dashboard.js
index 142b5bd..4e42436 100644
--- a/lib/api/routes/dashboard.js
+++ b/lib/api/routes/dashboard.js
@@ -11,7 +11,8 @@ router.use(requireOwner);
 const layoutSchema = z.object({
   card_order: z.array(z.string()).default([]),
   hidden: z.array(z.string()).default([]),
-  sizes: z.record(z.enum(['s', 'm', 'l'])).default({})
+  // Per-card width: an integer column span 1–12 (legacy 's'|'m'|'l' still accepted).
+  sizes: z.record(z.union([z.number().int().min(1).max(12), z.enum(['s', 'm', 'l'])])).default({})
 });
 
 router.get('/layout', asyncWrap(async (_req, res) => {
diff --git a/package.json b/package.json
index 4346872..c85141e 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "void-server",
-  "version": "2.0.0-alpha.12",
+  "version": "2.0.0-alpha.13",
   "type": "module",
   "private": true,
   "scripts": {
diff --git a/public/components/sv_card.js b/public/components/sv_card.js
index c30b4da..bc71854 100644
--- a/public/components/sv_card.js
+++ b/public/components/sv_card.js
@@ -4,7 +4,10 @@ import { el } from '../dom.js';
 // fills `body` in its mount(); start()/stop() own its refresh timer.
 export function svCard(def) {
   const body = el('div', { class: 'sv-card-body' });
-  const root = el('div', { class: 'sv-card', dataset: { size: def.size || 'm', cardId: def.id } },
+  const root = el('div', {
+      class: 'sv-card', dataset: { cardId: def.id },
+      style: { gridColumn: 'span ' + (def.span || 6) }   // 12-col grid; per-card width
+    },
     el('div', { class: 'sv-card-title' }, def.title),
     body
   );
diff --git a/public/style.css b/public/style.css
index 30a4243..fa25b38 100644
--- a/public/style.css
+++ b/public/style.css
@@ -174,12 +174,14 @@ ul.plain li:last-child { border-bottom: none; }
   /* reserved for a future agent-output phase — unused now:
      --hue-dross: #ff4f2e; --hue-yerin: #c45a4a; --hue-orthos: #6fa86a; */
 }
-#sv-cards { display: grid; grid-template-columns: repeat(6, 1fr); gap: 16px; align-items: start; }
-.sv-card { grid-column: span 2; }                /* s / fallback (factory always sets data-size) */
-.sv-card[data-size="s"] { grid-column: span 2; }
-.sv-card[data-size="m"] { grid-column: span 3; }
-.sv-card[data-size="l"] { grid-column: span 6; }
-@media (max-width: 900px) { #sv-cards { grid-template-columns: 1fr; } .sv-card { grid-column: 1 / -1 !important; } }
+#sv-cards { display: grid; grid-template-columns: repeat(12, 1fr); gap: 16px; align-items: start; }
+.sv-card { grid-column: span 6; }                /* fallback; svCard sets an inline span (1–12) */
+@media (max-width: 700px) { #sv-cards { grid-template-columns: 1fr; } .sv-card { grid-column: 1 / -1 !important; } }
+.sv-ed-span { display: inline-flex; align-items: center; gap: 3px; }
+.sv-ed-step { width: 18px; height: 20px; border: 1px solid var(--border); background: transparent; color: var(--muted);
+  border-radius: 3px; font-size: 13px; line-height: 1; cursor: pointer; padding: 0; }
+.sv-ed-step:hover { color: var(--accent); border-color: var(--accent-dim); }
+.sv-span-val { font-family: var(--font-mono); font-size: 11px; color: var(--text); min-width: 14px; text-align: center; }
 
 .sv-card {
   position: relative; border: 1px solid #2c242a; border-radius: 10px; padding: 16px 18px;
diff --git a/public/views/sacred_valley.js b/public/views/sacred_valley.js
index 45bce0e..5ccfcd1 100644
--- a/public/views/sacred_valley.js
+++ b/public/views/sacred_valley.js
@@ -29,18 +29,43 @@ async function saveLayout() {
 }
 
 // ---- per-card edit controls (drag grip + size + hide), shown only in edit mode via CSS
+const STR_SPAN = { s: 2, m: 6, l: 12 };   // legacy size → 12-col span (s = 1/6, m = 1/2, l = full)
+function spanOf(def) {
+  const v = layout.sizes?.[def.id];
+  if (typeof v === 'number') return Math.max(1, Math.min(12, v));
+  if (typeof v === 'string') return STR_SPAN[v] || 6;
+  return STR_SPAN[def.size] || 6;
+}
+function curSpan(id) {
+  const node = grid().querySelector(`.sv-card[data-card-id="${id}"]`);
+  const m = node && (node.style.gridColumn || '').match(/span (\d+)/);
+  return m ? +m[1] : spanOf(BY_ID.get(id) || {});
+}
+function setSpan(id, delta) {
+  const span = Math.max(1, Math.min(12, curSpan(id) + delta));
+  layout.sizes = { ...layout.sizes, [id]: span };
+  const node = grid().querySelector(`.sv-card[data-card-id="${id}"]`);
+  if (node) {
+    node.style.gridColumn = 'span ' + span;
+    const lbl = node.querySelector('.sv-span-val');
+    if (lbl) lbl.textContent = span;
+  }
+  saveLayout();
+}
+
 function editOverlay(def) {
   const grip = el('span', { class: 'sv-grip', draggable: true, title: 'Drag to reorder' }, '⠿');
-  const sizes = el('span', { class: 'sv-ed-sizes' },
-    ...['s', 'm', 'l'].map(s =>
-      el('button', { class: 'sv-ed-size', dataset: { s }, onclick: () => setSize(def.id, s) }, s.toUpperCase())));
+  const stepper = el('span', { class: 'sv-ed-span' },
+    el('button', { class: 'sv-ed-step', title: 'Narrower', onclick: () => setSpan(def.id, -1) }, '−'),
+    el('span', { class: 'sv-span-val', title: 'Width (of 12)' }, String(spanOf(def))),
+    el('button', { class: 'sv-ed-step', title: 'Wider', onclick: () => setSpan(def.id, +1) }, '+'));
   const hide = el('button', { class: 'sv-ed-hide', title: 'Hide card', onclick: () => hideCard(def.id) }, '✕');
-  return el('div', { class: 'sv-card-edit' }, grip, sizes, hide);
+  return el('div', { class: 'sv-card-edit' }, grip, stepper, hide);
 }
 
 function mountOne(def) {
-  const size = layout.sizes?.[def.id] || def.size;
-  const { root, body } = svCard({ ...def, size });
+  const span = spanOf(def);
+  const { root, body } = svCard({ ...def, span });
   root.appendChild(editOverlay(def));
   grid().appendChild(root);
   try { def.mount(body); def.start && def.start(); active.push(def); }
diff --git a/server.js b/server.js
index 7a38e8d..46d9f46 100644
--- a/server.js
+++ b/server.js
@@ -10,7 +10,7 @@ import { router as iconsRouter } from './lib/api/routes/icons.js';
 import { startCron } from './lib/cron/index.js';
 import { seedFromConfig } from './lib/health/registry.js';
 
-const VERSION = '2.0.0-alpha.12';
+const VERSION = '2.0.0-alpha.13';
 
 export function createApp() {
   const app = express();