diff --git a/App.jsx b/App.jsx
index 05b8a7d..4a2d60c 100644
--- a/App.jsx
+++ b/App.jsx
@@ -281,6 +281,7 @@ const blankProduct = () => ({
 function isUpsCategory(cat) {
   return !!cat && (cat.id === 'ups' || cat.name === 'UPS不间断电源');
 }
+function spaceToAsterisk(v) { return (v || '').replace(/ /g, '*'); }
 function computeMaxPowerKW(ratedPower, ratedPowerUnit, powerFactor) {
   const rp = parseFloat(ratedPower);
   const pf = parseFloat(powerFactor);
@@ -3055,7 +3056,15 @@ function ProductForm({ draft, setDraft, onSave, onCancel, categories, onManage }
               <span className="field-label">产品大类 *</span>
               <span className="field-manage-link" onClick={() => onManage('category')}><Settings2 size={11} />大类管理</span>
             </div>
-            <select className="select" value={draft.category} onChange={e => set({ category: e.target.value, brand: '', type: '', machineVariant: '' })}>
+            <select
+              className="select" value={draft.category}
+              onChange={e => {
+                const newCatId = e.target.value;
+                const newCat = (categories || []).find(c => c.id === newCatId);
+                const defaultBrand = (newCat && newCat.brands && newCat.brands.length) ? newCat.brands[0] : '';
+                set({ category: newCatId, brand: defaultBrand, type: '', machineVariant: '' });
+              }}
+            >
               <option value="">请选择</option>
               {(categories || []).map(c => <option key={c.id} value={c.id}>{c.name}</option>)}
             </select>
@@ -3164,7 +3173,7 @@ function ProductForm({ draft, setDraft, onSave, onCancel, categories, onManage }
               </div>
               <div className="field">
                 <span className="field-label">电池数量和容量</span>
-                <input className="input" value={draft.batterySpec} onChange={e => set({ batterySpec: e.target.value })} placeholder="如：5000mAh*4" />
+                <input className="input" value={draft.batterySpec} onChange={e => set({ batterySpec: spaceToAsterisk(e.target.value) })} placeholder="如：5000mAh*4" />
               </div>
             </div>
             <div className="field">
@@ -3190,7 +3199,7 @@ function ProductForm({ draft, setDraft, onSave, onCancel, categories, onManage }
               </div>
             )}
             <div className="grid-2">
-              <div className="field"><span className="field-label">尺寸（mm）</span><input className="input" value={draft.dimensions} onChange={e => set({ dimensions: e.target.value })} placeholder="如：210*130*40" /></div>
+              <div className="field"><span className="field-label">尺寸（mm）</span><input className="input" value={draft.dimensions} onChange={e => set({ dimensions: spaceToAsterisk(e.target.value) })} placeholder="如：210*130*40" /></div>
               <div className="field"><span className="field-label">净重（kg）</span><input className="input" value={draft.netWeight} onChange={e => set({ netWeight: e.target.value })} placeholder="如：0.73" /></div>
             </div>
           </>