优化领取页第一步文案示意与 Mock 表单

- 游戏编号文案与红色提示，底部增加编号位置示意图
- 压缩商品信息卡片，示意图移至最下方
- 开发 Mock 在待填 UID 步骤下 UID 改为可选

apps/frontend/src/styles/main.css

@@ -757,6 +757,63 @@ select {
   gap: 14px;
 }
 
+.claim-info-grid-compact {
+  gap: 8px;
+  margin-bottom: 10px;
+}
+
+.claim-info-grid-compact .claim-info-item {
+  padding: 8px 10px;
+  gap: 2px;
+  border-radius: 6px;
+}
+
+.claim-info-grid-compact .claim-info-item span {
+  font-size: 11px;
+  line-height: 1.3;
+}
+
+.claim-info-grid-compact .claim-info-item strong {
+  font-size: 13px;
+  line-height: 1.35;
+  font-weight: 600;
+}
+
+.claim-uid-guide {
+  margin: 14px 0 0;
+  padding: 8px;
+  border-radius: 10px;
+  background: #f8fafc;
+  border: 1px solid #e5e7eb;
+}
+
+.claim-uid-guide-image {
+  display: block;
+  width: 100%;
+  max-width: 420px;
+  margin: 0 auto;
+  border-radius: 8px;
+  border: 1px solid #e2e8f0;
+  object-fit: contain;
+  background: #fff;
+}
+
+.claim-uid-guide-caption {
+  margin: 8px 0 0;
+  text-align: center;
+  color: #64748b;
+  font-size: 12px;
+  line-height: 1.4;
+}
+
+.claim-uid-warning {
+  margin: 14px 0 0;
+  color: #ff4d4f;
+  font-size: 13px;
+  font-weight: 600;
+  line-height: 1.5;
+}
+
 .claim-info-item {
   min-width: 0;
   padding: 16px;