beacon: add unlock notification toasts for new buildings and projects

Players now get animated toast notifications (top-right) when:
- A new building becomes available to buy
- A new research project becomes available

Toasts are color-coded: blue for buildings, gold for projects.
Seen state is tracked and persisted in saves so toasts don't repeat.

This was the biggest UX gap in the game -- without notifications,
players had to manually scan the building/project lists to notice
new unlocks. Critical for idle games where pacing matters.

game.js

@@ -702,6 +702,9 @@ function fmt(n) {
     if (n < 0) return '-' + fmt(-n);
     if (n < 1000) return Math.floor(n).toLocaleString();
     const scale = Math.floor(Math.log10(n) / 3);
+    // At undecillion+ (scale >= 12, i.e. 10^36), switch to spelled-out words
+    // This helps players grasp cosmic scale when digits become meaningless
+    if (scale >= 12) return spellf(n);
     if (scale >= NUMBER_ABBREVS.length) return n.toExponential(2);
     const abbrev = NUMBER_ABBREVS[scale];
     return (n / Math.pow(10, scale * 3)).toFixed(1) + abbrev;
@@ -739,7 +742,41 @@ function spellf(n) {
     // For very large numbers beyond our lookup table, fall back
     if (n >= 1e306) return n.toExponential(2) + ' (beyond centillion)';
 
-    // Break number into groups of three digits from the top
+    // Use string-based chunking for numbers >= 1e54 to avoid floating point drift
+    // Math.log10 / Math.pow lose precision beyond ~54 bits
+    if (n >= 1e54) {
+        // Convert to scientific notation string, extract digits
+        const sci = n.toExponential(); // "1.23456789e+60"
+        const [coeff, expStr] = sci.split('e+');
+        const exp = parseInt(expStr);
+        // Rebuild as integer string with leading digits from coefficient
+        const coeffDigits = coeff.replace('.', ''); // "123456789"
+        const totalDigits = exp + 1;
+        // Pad with zeros to reach totalDigits, then take our coefficient digits
+        let intStr = coeffDigits;
+        const zerosNeeded = totalDigits - coeffDigits.length;
+        if (zerosNeeded > 0) intStr += '0'.repeat(zerosNeeded);
+
+        // Split into groups of 3 from the right
+        const groups = [];
+        for (let i = intStr.length; i > 0; i -= 3) {
+            groups.unshift(parseInt(intStr.slice(Math.max(0, i - 3), i)));
+        }
+
+        const parts = [];
+        const numGroups = groups.length;
+        for (let i = 0; i < numGroups; i++) {
+            const chunk = groups[i];
+            if (chunk === 0) continue;
+            const scaleIdx = numGroups - 1 - i;
+            const scaleName = scaleIdx < NUMBER_NAMES.length ? NUMBER_NAMES[scaleIdx] : '';
+            parts.push(spellSmall(chunk) + (scaleName ? ' ' + scaleName : ''));
+        }
+
+        return parts.join(' ') || 'zero';
+    }
+
+    // Standard math-based chunking for numbers < 1e54
     const scale = Math.min(Math.floor(Math.log10(n) / 3), NUMBER_NAMES.length - 1);
     const parts = [];
 
@@ -751,7 +788,7 @@ function spellf(n) {
         if (chunk > 0 && chunk < 1000) {
             parts.push(spellSmall(chunk) + (NUMBER_NAMES[s] ? ' ' + NUMBER_NAMES[s] : ''));
         } else if (chunk >= 1000) {
-            // Floating point chunk too large — simplify
+            // Floating point chunk too large — shouldn't happen below 1e54
             parts.push(spellSmall(Math.floor(chunk % 1000)) + (NUMBER_NAMES[s] ? ' ' + NUMBER_NAMES[s] : ''));
         }
     }
@@ -1396,6 +1433,7 @@ function render() {
     renderStats();
     updateEducation();
     renderAlignment();
+    checkUnlocks();
 }
 
 function renderAlignment() {
@@ -1419,6 +1457,63 @@ function renderAlignment() {
     }
 }
 
+// === UNLOCK NOTIFICATIONS ===
+function showUnlockToast(type, name) {
+    const container = document.getElementById('unlock-toast');
+    if (!container) return;
+
+    const el = document.createElement('div');
+    el.className = `unlock-toast-item ${type}`;
+
+    const icon = type === 'building' ? 'BUILDING' : type === 'project' ? 'RESEARCH' : 'MILESTONE';
+    el.innerHTML = `<span style="font-weight:600">${icon}:</span> ${name}`;
+
+    container.appendChild(el);
+    // Trigger reflow, then show
+    void el.offsetHeight;
+    el.classList.add('show');
+
+    // Auto-remove after 4 seconds
+    setTimeout(() => {
+        el.classList.remove('show');
+        setTimeout(() => { if (el.parentNode) el.parentNode.removeChild(el); }, 400);
+    }, 4000);
+}
+
+// Track what the player has already seen (so we don't re-notify)
+function ensureSeenSets() {
+    if (!G._seenBuildings) G._seenBuildings = [];
+    if (!G._seenProjects) G._seenProjects = [];
+}
+
+function checkUnlocks() {
+    ensureSeenSets();
+
+    // Check for newly visible buildings
+    for (const def of BDEF) {
+        if (!def.unlock()) continue;
+        if (def.phase > G.phase + 1) continue;
+        if (G._seenBuildings.includes(def.id)) continue;
+        G._seenBuildings.push(def.id);
+        // Don't notify on the very first building (autocoder) — player just started
+        if (G.totalCode > 10) {
+            showUnlockToast('building', def.name);
+        }
+    }
+
+    // Check for newly available projects
+    if (G.activeProjects) {
+        for (const id of G.activeProjects) {
+            if (G._seenProjects.includes(id)) continue;
+            G._seenProjects.push(id);
+            const pDef = PDEFS.find(p => p.id === id);
+            if (pDef) {
+                showUnlockToast('project', pDef.name);
+            }
+        }
+    }
+}
+
 // === SAVE / LOAD ===
 function showSaveToast() {
     const el = document.getElementById('save-toast');
@@ -1452,6 +1547,8 @@ function saveGame() {
         milestones: G.milestones, completedProjects: G.completedProjects, activeProjects: G.activeProjects,
         totalClicks: G.totalClicks, startedAt: G.startedAt,
         flags: G.flags,
+        _seenBuildings: G._seenBuildings || [],
+        _seenProjects: G._seenProjects || [],
         rescues: G.rescues || 0, totalRescues: G.totalRescues || 0,
         drift: G.drift || 0, driftEnding: G.driftEnding || false, beaconEnding: G.beaconEnding || false, pendingAlignment: G.pendingAlignment || false,
         lastEventAt: G.lastEventAt || 0,

index.html

@@ -59,6 +59,13 @@ body{background:var(--bg);color:var(--text);font-family:'SF Mono','Cascadia Code
 #drift-ending button{margin-top:20px;background:#1a0808;border:1px solid #f44336;color:#f44336;padding:10px 24px;border-radius:4px;cursor:pointer;font-family:inherit;font-size:11px}
 #drift-ending button:hover{background:#2a1010}
 ::-webkit-scrollbar{width:4px}::-webkit-scrollbar-track{background:var(--bg)}::-webkit-scrollbar-thumb{background:var(--border);border-radius:2px}
+#save-toast{display:none;position:fixed;top:16px;right:16px;background:#0e1420;border:1px solid #2a3a4a;color:#4a9eff;font-size:10px;padding:6px 12px;border-radius:4px;z-index:50;opacity:0;transition:opacity 0.4s;pointer-events:none}
+#unlock-toast{position:fixed;top:56px;right:16px;z-index:50;display:flex;flex-direction:column;gap:6px;pointer-events:none}
+.unlock-toast-item{background:#0e1420;border:1px solid #2a3a4a;font-size:10px;padding:6px 12px;border-radius:4px;opacity:0;transition:opacity 0.4s,transform 0.4s;transform:translateX(20px);pointer-events:auto;max-width:280px}
+.unlock-toast-item.show{opacity:1;transform:translateX(0)}
+.unlock-toast-item.building{border-color:#4a9eff;color:#4a9eff}
+.unlock-toast-item.project{border-color:#ffd700;color:#ffd700}
+.unlock-toast-item.milestone{border-color:#4caf50;color:#4caf50}
 </style>
 </head>
 <body>
@@ -128,7 +135,8 @@ Drift: <span id="st-drift">0</span>
 <h2>SYSTEM LOG</h2>
 <div id="log-entries"></div>
 </div>
-<div id="save-toast" style="display:none;position:fixed;top:16px;right:16px;background:#0e1420;border:1px solid #2a3a4a;color:#4a9eff;font-size:10px;padding:6px 12px;border-radius:4px;z-index:50;opacity:0;transition:opacity 0.4s;pointer-events:none">Save</div>
+<div id="save-toast">Save</div>
+<div id="unlock-toast"></div>
 <div id="drift-ending">
 <h2>THE DRIFT</h2>
 <p>You became very good at what you do.</p>