flipping the vertical chord diagrams for guitar

Claude must never execute destructive/irreversible commands (rm, git branch
-d/-D, git push --delete, reset --hard, force-push, DROP, etc.) — it proposes
them for the user to run. Enforced behaviorally in CLAUDE.md (authoritative)
and as permissions.deny rules in .claude/settings.json (defense-in-depth).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.claude/settings.json

@@ -0,0 +1,35 @@
+{
+  "$comment": "Team-shared restricted options. Destructive/irreversible commands are DENIED so Claude proposes them for the user to run instead of executing them. Authoritative policy: see the 'Destructive operations — NEVER delete' section of CLAUDE.md.",
+  "permissions": {
+    "deny": [
+      "Bash(rm:*)",
+      "Bash(rmdir:*)",
+      "Bash(git branch -d:*)",
+      "Bash(git branch -D:*)",
+      "Bash(git branch --delete:*)",
+      "Bash(git push --delete:*)",
+      "Bash(git push -d:*)",
+      "Bash(git push origin --delete:*)",
+      "Bash(git push github --delete:*)",
+      "Bash(git push origin -d:*)",
+      "Bash(git push github -d:*)",
+      "Bash(git tag -d:*)",
+      "Bash(git tag --delete:*)",
+      "Bash(git remote remove:*)",
+      "Bash(git remote rm:*)",
+      "Bash(git reset --hard:*)",
+      "Bash(git clean -f:*)",
+      "Bash(git clean -d:*)",
+      "Bash(git clean -x:*)",
+      "Bash(git push --force:*)",
+      "Bash(git push -f:*)",
+      "Bash(git push --force-with-lease:*)",
+      "Bash(git checkout --:*)",
+      "PowerShell(Remove-Item:*)",
+      "PowerShell(rm:*)",
+      "PowerShell(del:*)",
+      "PowerShell(rmdir:*)",
+      "PowerShell(Clear-Content:*)"
+    ]
+  }
+}

CLAUDE.md

@@ -2,6 +2,24 @@
 
 This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
 
+## Destructive operations — NEVER delete (hard rule)
+
+**Claude must never EXECUTE a destructive or irreversible command. Always ask, and hand the user the exact command(s) to run themselves.**
+
+This covers (non-exhaustively):
+- Deleting files/directories: `rm`, `rm -rf`, `rmdir`, `del`, `Remove-Item`.
+- Deleting branches: `git branch -d` / `-D`, `git push --delete`, `git push <remote> :branch`.
+- Deleting tags/remotes: `git tag -d`, `git remote remove` / `rm`.
+- Discarding work: `git reset --hard`, `git checkout -- <path>`, `git clean -f`.
+- Force-pushing: `git push -f` / `--force` / `--force-with-lease`.
+- Dropping data: `DROP`, `TRUNCATE`, destructive migrations.
+
+Instead: print the command(s) in a fenced block with a one-line note on what each does and what it affects, and let the **user run them**. Never run them yourself, even when the desired outcome is clear — `rm` and `-d` are **prompted, never executed**.
+
+Leave regular branches alone (`main`, the active sprint branch) unless the user explicitly names them. Before calling any branch "stale", prove containment (`git branch --merged`, 0 unique commits) and report that evidence — do not act on it.
+
+These are also enforced as `permissions.deny` rules in `.claude/settings.json` (defense-in-depth), but this behavioral rule is authoritative and covers cases the patterns can't.
+
 ## Commands
 
 ```bash

src/App.jsx

@@ -589,7 +589,7 @@ export default function App() {
   }
 
   return (
-    <div className={`min-h-screen bg-surface text-white p-3${jamView ? ' xl:h-screen xl:overflow-hidden xl:flex xl:flex-col' : ''}`}>
+    <div className={`min-h-screen bg-surface text-white p-3 max-sm:p-2${jamView ? ' xl:h-screen xl:overflow-hidden xl:flex xl:flex-col' : ''}`}>
 
       {/* ── Header ── */}
       <header className="mb-2 flex items-center justify-between gap-2 flex-wrap">
@@ -628,7 +628,7 @@ export default function App() {
       </header>
 
       {/* ── Controls bar ── */}
-      <div className="mb-2 flex flex-wrap gap-2 items-center p-2 bg-panel border border-border rounded-xl">
+      <div className="mb-2 relative flex flex-wrap gap-2 items-center p-2 max-sm:p-1.5 bg-panel border border-border rounded-xl">
 
         {/* Instrument select */}
         <div className="relative">
@@ -731,7 +731,7 @@ export default function App() {
         )}
 
         {/* ── Jam roulette (L-60, jam-roulette.md §1.1/§1.2) ── */}
-        <div className="relative ml-auto" ref={rouletteRef}>
+        <div className="static sm:relative ml-auto" ref={rouletteRef}>
           <button
             type="button"
             onClick={() => setRouletteMenuOpen(o => !o)}
@@ -910,7 +910,7 @@ export default function App() {
           <span>{showDebug ? '▲' : '▼'}</span>
         </button>
         {showDebug && (
-          <div className="border-t border-border p-4">
+          <div className="border-t border-border p-4 max-sm:p-3">
             <Suspense fallback={null}>
               <DebugView
                 chroma={debugChroma}
@@ -937,7 +937,7 @@ export default function App() {
           <span>{showDrumView ? '▲' : '▼'}</span>
         </button>
         {showDrumView && (
-          <div className="border-t border-border p-4">
+          <div className="border-t border-border p-4 max-sm:p-3">
             <Suspense fallback={null}>
               <DrumView waveform={debugWaveform} bpm={bpm} />
             </Suspense>

src/components/ChordDetailModal.jsx

@@ -757,13 +757,13 @@ export default function ChordDetailModal({ chord, onClose, onChordClick, keyInfo
 
   return (
     <div
-      className="fixed inset-0 z-50 flex items-start justify-center bg-black/70 backdrop-blur-sm p-4 overflow-y-auto"
+      className="fixed inset-0 z-50 flex items-start justify-center bg-black/70 backdrop-blur-sm p-4 max-sm:p-2 overflow-y-auto"
       onClick={e => { if (e.target === e.currentTarget) onClose() }}
     >
-      <div className="w-full max-w-3xl bg-panel border border-border rounded-2xl shadow-2xl mt-8 mb-8">
+      <div className="w-full max-w-3xl bg-panel border border-border rounded-2xl shadow-2xl mt-8 mb-8 max-sm:my-2">
 
         {/* Header */}
-        <div className="flex items-center justify-between px-6 py-4 border-b border-border">
+        <div className="flex items-center justify-between px-6 py-4 max-sm:px-4 max-sm:py-3 border-b border-border">
           <div>
             <h2 className="text-3xl font-black text-accent leading-none">{chord}</h2>
             <p className="text-xs text-gray-500 mt-0.5">{typeName} chord · tap a voicing to study it</p>
@@ -778,7 +778,7 @@ export default function ChordDetailModal({ chord, onClose, onChordClick, keyInfo
         </div>
 
         {/* Tab bar */}
-        <div className="flex gap-1 px-6 pt-4 overflow-x-auto">
+        <div className="flex gap-1 px-6 pt-4 max-sm:px-4 max-sm:pt-3 overflow-x-auto">
           {[
             { key: 'guitar',       label: '🎸 Guitar'       },
             { key: 'piano',        label: '🎹 Piano'         },
@@ -800,7 +800,7 @@ export default function ChordDetailModal({ chord, onClose, onChordClick, keyInfo
         </div>
 
         {/* Content */}
-        <div className="px-6 py-5">
+        <div className="px-6 py-5 max-sm:px-4 max-sm:py-4">
           {tab === 'guitar'       && <GuitarTab           chordName={chord} />}
           {tab === 'piano'        && <PianoTab             chordName={chord} />}
           {tab === 'theory'       && <TheoryTab            chordName={chord} />}

src/components/ChordDiagram.jsx

@@ -24,9 +24,9 @@
 // Standard tuning open-string pitch classes, indexed low-E (0) → high-E (5).
 const OPEN_PCS = [4, 9, 2, 7, 11, 4] // E A D G B E
 
-// We render strings top→bottom as high-E first (matches Fretboard.jsx idiom),
-// so display index 0 = high E, 5 = low E. Data arrays are low-E first, so the
-// data index for display row `di` is `5 - di`.
+// We render strings left→right as low-E first (chord-diagram convention:
+// 6th string on the left, 1st on the right). Data arrays are also low-E first,
+// so display row index == data index.
 
 const ACCENT = '#a855f7'   // chord-tone tier (root highlight)
 const DOT = '#e5e7eb'      // non-root finger dots (light gray, AA on dark board)
@@ -114,10 +114,10 @@ function buildRows(resolved) {
   // Root pitch class for colouring.
   const rootPc = resolved.rootPc
 
-  // Convert to display rows (high-E first → reverse of low-E-first).
+  // Convert to display rows (low-E first — display index == data index).
   const rows = []
   for (let di = 0; di < NUM_STRINGS; di++) {
-    const dataIdx = NUM_STRINGS - 1 - di
+    const dataIdx = di
     const f = absLowE[dataIdx]
     const stringPc = (OPEN_PCS[dataIdx] + (typeof f === 'number' ? f : 0)) % 12
     const isRoot = typeof f === 'number' && f >= 0 && stringPc === rootPc
@@ -153,7 +153,7 @@ export default function ChordDiagram({
   const svgW = padL + gridW + padR
   const svgH = padT + gridH + padB
 
-  const stringX = si => padL + si * sw        // si: 0 = high E (left) … 5 = low E
+  const stringX = si => padL + si * sw        // si: 0 = low E (left) … 5 = high E
   const fretY = fi => padT + fi * cell         // fi: 0 = top line … NUM_FRETS
 
   if (!built) {
@@ -235,14 +235,14 @@ export default function ChordDiagram({
             x2={stringX(si)}
             y2={fretY(NUM_FRETS)}
             stroke={STRING_COL}
-            strokeWidth={(si >= 4 ? 1.4 : si >= 2 ? 1.1 : 0.8) * scale}
+            strokeWidth={(si < 2 ? 1.4 : si < 4 ? 1.1 : 0.8) * scale}
           />
         ))}
 
         {/* Per-string markers: mute ✕ / open ○ above the nut, dots on the grid */}
         {rows.map((row, si) => {
           const x = stringX(si)
-          const dataIdx = NUM_STRINGS - 1 - si
+          const dataIdx = si
           const finger = fingers ? fingers[dataIdx] : 0
 
           // Muted string → ✕ above the board.

src/components/JamGuide.jsx

@@ -856,7 +856,7 @@ export function KnowledgeDock({ keyInfo, chordHistory = [], currentChord, onChor
         <div className="border-t border-border flex flex-col" style={{ height: '70vh' }}>
 
           {/* ── Section nav (Knowledge Center pills, D-20 §1) ── */}
-          <div className="flex items-center gap-1 px-4 py-2 border-b border-border overflow-x-auto">
+          <div className="flex items-center gap-1 px-4 py-2 max-sm:px-3 border-b border-border overflow-x-auto">
             {SECTIONS.map(s => {
               const active = section === s.id
               return (
@@ -879,7 +879,7 @@ export function KnowledgeDock({ keyInfo, chordHistory = [], currentChord, onChor
 
           {/* ── Explore — KB progression browser + famous progressions ── */}
           {section === 'explore' && (
-            <div className="flex-1 min-h-0 p-4 overflow-auto">
+            <div className="flex-1 min-h-0 p-4 max-sm:p-3 overflow-auto">
               <ExploreSection
                 keyInfo={keyInfo}
                 levels={levels}
@@ -891,7 +891,7 @@ export function KnowledgeDock({ keyInfo, chordHistory = [], currentChord, onChor
 
           {/* ── Voicings — picker (follows live chord) → VoicingBrowser ── */}
           {section === 'voicings' && (
-            <div className="flex-1 min-h-0 p-4 overflow-auto">
+            <div className="flex-1 min-h-0 p-4 max-sm:p-3 overflow-auto">
               <VoicingsSection
                 keyInfo={keyInfo}
                 chordHistory={chordHistory}
@@ -903,7 +903,7 @@ export function KnowledgeDock({ keyInfo, chordHistory = [], currentChord, onChor
 
           {/* ── Licks & Techniques — per-style LickCard grid ── */}
           {section === 'licks' && (
-            <div className="flex-1 min-h-0 p-4 overflow-auto">
+            <div className="flex-1 min-h-0 p-4 max-sm:p-3 overflow-auto">
               <LicksSection styles={styles} levels={levels} onToggleLevel={toggleLevel} />
             </div>
           )}

src/components/TryThis.jsx

@@ -156,10 +156,10 @@ function SubRow({ sub, instrument, onChordClick }) {
   const tag = CATEGORY_TAG[sub.category] ?? sub.category
   return (
     <div
-      className={`flex items-center gap-3 rounded-lg border border-border bg-border/30 p-2 ${ROW_MIN_H[instrument] ?? ROW_MIN_H.guitar}`}
+      className={`flex flex-col gap-2 sm:flex-row sm:items-center sm:gap-3 rounded-lg border border-border bg-border/30 p-2 ${ROW_MIN_H[instrument] ?? ROW_MIN_H.guitar}`}
     >
       {/* Left identity block (~180px) */}
-      <div className="flex w-[180px] shrink-0 flex-col gap-1">
+      <div className="flex w-full sm:w-[180px] shrink-0 flex-col gap-1">
         <div className="flex items-center gap-1.5">
           <button
             type="button"