Add pinned Daily Practice card + one-tap mode

- Daily Practice (all 31 prepositions) is pinned to the top of the
  Prepositions tab once the "Alle Präpositionen" lesson is passed
  (>=70% over a full round).
- One-tap mode: after answering, the app flashes right/wrong and
  auto-advances. Always on in Daily Practice; a persisted "One-tap"
  toggle in the practice header enables it for any other level.

src/App.jsx

@@ -60,7 +60,10 @@ const TABS = [
   {id:'pronoun', label:'Pronouns'},
 ];
 
-const FREE_LEVEL_IDS = new Set([2, 3, 4, 8, 9, 10, 18]);
+// Daily Practice pseudo-level: pinned to the top of the Prepositions tab once
+// the "Alle Präpositionen" lesson (id 10) is completed. Always free.
+const DAILY_ID = 10.5;
+const FREE_LEVEL_IDS = new Set([2, 3, 4, 8, 9, 10, 10.5, 18]);
 const CORE_ARTICLE_CASES = ['nominative', 'accusative', 'dative'];
 const PAYMENTS_ENABLED = import.meta.env.VITE_PAYMENTS_ENABLED === 'true';
 const STRIPE_PLANS = PAYMENTS_ENABLED ? [
@@ -220,7 +223,7 @@ export default function App() {
   const nextLevelInTab = (id) => {
     const lvObj = LEVELS.find(l => l.id === id);
     if (!lvObj) return null;
-    const tabLevels = LEVELS.filter(l => l.tab === lvObj.tab).sort((a,b) => a.id - b.id);
+    const tabLevels = LEVELS.filter(l => l.tab === lvObj.tab && !l.daily).sort((a,b) => a.id - b.id);
     const idx = tabLevels.findIndex(l => l.id === id);
     if (idx === -1 || idx === tabLevels.length - 1) return null;
     return tabLevels[idx + 1];
@@ -297,12 +300,30 @@ export default function App() {
     return () => window.removeEventListener('keydown', h);
   });
 
+  // One-tap mode: after an answer is revealed, auto-advance to the next
+  // question. Always on in Daily Practice; opt-in (st.auto) elsewhere. Correct
+  // answers flash briefly; wrong answers linger so the correction can register.
+  useEffect(() => {
+    if (scr !== 'practice' || !rev) return;
+    const quick = lv === DAILY_ID || !!st.auto;
+    if (!quick) return;
+    const t = setTimeout(() => { nextRef.current?.(); }, ok ? 750 : 1650);
+    return () => clearTimeout(t);
+  }, [scr, rev, ok, lv, st.auto]);
+
   if (!loaded) return <div style={S.wrap}><p style={{color:'#999',textAlign:'center',paddingTop:120}}>Loading...</p></div>;
 
   const rc = res.filter(Boolean).length;
   const cur = LEVELS.find(l=>l.id===lv);
   const chartSection = scr === 'menu' ? tab : (q?.type === 'wechselContext' ? 'prep' : q?.type === 'chunk' ? 'article' : (q?.type || tab));
   const nextInTab = nextLevelInTab(lv);
+  const quickActive = lv === DAILY_ID || !!st.auto;
+  // Daily Practice unlocks once the all-31 lesson (id 10) is passed:
+  // at least one full round with the app's 70% pass rate.
+  const prepMastery = st.sc?.[10];
+  const dailyUnlocked = !!(prepMastery && prepMastery.t >= ROUND && prepMastery.c / prepMastery.t >= 0.7);
+  const dailySc = st.sc?.[DAILY_ID];
+  const dailyPct = dailySc ? Math.round(dailySc.c / dailySc.t * 100) : null;
 
   return (
     <div style={S.wrap}>
@@ -314,6 +335,14 @@ export default function App() {
             ? <button style={S.linkBtn} onClick={()=>setScr('menu')}>← back</button>
             : <div style={S.logo}>Beug</div>}
           <div style={{display:'flex',gap:14,alignItems:'center'}}>
+            {scr === 'practice' && (
+              <button
+                style={{...S.linkBtn, color: quickActive ? GREEN : '#999', fontWeight: quickActive ? 700 : 500}}
+                title={lv === DAILY_ID ? 'One-tap is always on in Daily Practice' : 'Answer with one tap, then auto-advance'}
+                onClick={()=>{ if (lv === DAILY_ID) return; save({...st, auto: !st.auto}); }}>
+                ⚡ {quickActive ? 'One-tap' : 'One-tap off'}
+              </button>
+            )}
             {scr === 'practice' && <button style={S.linkBtn} onClick={()=>setChart(true)}>charts</button>}
             {PAYMENTS_ENABLED && hasPaidAccess && <span style={S.stat}>Unlocked</span>}
             <StreakBadge st={st}/>
@@ -342,6 +371,17 @@ export default function App() {
             </div>
 
             <div style={{marginTop:10}}>
+              {tab === 'prep' && dailyUnlocked && (
+                <div style={{...S.lvRow, cursor:'pointer', border:`1.5px solid ${GREEN}`, background:'#f3ffe8'}}
+                  onClick={()=>startLv(DAILY_ID)}>
+                  <div style={{flex:1, minWidth:0}}>
+                    <div style={S.lvName}>⚡ Daily Practice</div>
+                    <div style={S.lvDesc}>All 31 prepositions · one-tap · keep them sharp</div>
+                    {dailySc && <div style={{fontSize:11,color:'#bbb',marginTop:3}}>{dailySc.c}/{dailySc.t}</div>}
+                  </div>
+                  {dailyPct !== null && <div style={{...S.lvPct, color:dailyPct>=70?GREEN:RED}}>{dailyPct}%</div>}
+                </div>
+              )}
               {tab === 'prep' && (
                 <div style={{...S.lvRow, cursor:'pointer'}}
                   onClick={()=>{ setLearnStep(0); setScr('learn'); }}>
@@ -351,7 +391,7 @@ export default function App() {
                   </div>
                 </div>
               )}
-              {LEVELS.filter(l => l.tab === tab).sort((a,b)=>a.id-b.id).map(l => {
+              {LEVELS.filter(l => l.tab === tab && !l.daily).sort((a,b)=>a.id-b.id).map(l => {
                 const u = unlocked(l.id);
                 const s = st.sc[l.id];
                 const p = s ? Math.round(s.c/s.t*100) : null;
@@ -467,7 +507,7 @@ export default function App() {
                       color: rev?(ok?GREEN:RED):'#1a1a1a',
                       minWidth: q.type==='poss' ? 110 : 80,
                     }}>
-                      {rev ? q.ans : (inp || '\u00A0\u00A0\u00A0\u00A0\u00A0')}
+                      {rev ? q.ans : (inp || '     ')}
                     </span>
                   )}
                 </span>