add price policy

lib/features/price_policy/presentation/widgets/document_card.dart

@@ -0,0 +1,169 @@
+import 'package:flutter/material.dart';
+import '../../../../core/constants/ui_constants.dart';
+import '../../../../core/theme/colors.dart';
+import '../../domain/entities/price_document.dart';
+
+/// Document card widget displaying price policy or price list document
+class DocumentCard extends StatelessWidget {
+  final PriceDocument document;
+  final VoidCallback onDownload;
+
+  const DocumentCard({
+    super.key,
+    required this.document,
+    required this.onDownload,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      decoration: BoxDecoration(
+        color: AppColors.white,
+        borderRadius: BorderRadius.circular(12),
+        border: Border.all(color: AppColors.grey100),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withOpacity(0.05),
+            blurRadius: 4,
+            offset: const Offset(0, 2),
+          ),
+        ],
+      ),
+      child: Material(
+        color: Colors.transparent,
+        child: InkWell(
+          borderRadius: BorderRadius.circular(12),
+          onTap: onDownload,
+          child: Padding(
+            padding: const EdgeInsets.all(AppSpacing.md),
+            child: LayoutBuilder(
+              builder: (context, constraints) {
+                // Responsive layout: column on mobile, row on larger screens
+                final isNarrow = constraints.maxWidth < 600;
+
+                if (isNarrow) {
+                  return Column(
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: [
+                      Row(
+                        children: [
+                          _buildIcon(),
+                          const SizedBox(width: AppSpacing.md),
+                          Expanded(child: _buildInfo()),
+                        ],
+                      ),
+                      const SizedBox(height: AppSpacing.md),
+                      SizedBox(
+                        width: double.infinity,
+                        child: _buildDownloadButton(),
+                      ),
+                    ],
+                  );
+                }
+
+                return Row(
+                  children: [
+                    _buildIcon(),
+                    const SizedBox(width: AppSpacing.md),
+                    Expanded(child: _buildInfo()),
+                    const SizedBox(width: AppSpacing.md),
+                    _buildDownloadButton(),
+                  ],
+                );
+              },
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildIcon() {
+    final iconData = document.isPdf ? Icons.picture_as_pdf : Icons.table_chart;
+    final iconColor = document.isPdf
+        ? Colors.red.shade600
+        : Colors.green.shade600;
+
+    return Container(
+      width: 50,
+      height: 50,
+      decoration: BoxDecoration(
+        color: AppColors.grey50,
+        borderRadius: BorderRadius.circular(8),
+      ),
+      child: Icon(iconData, size: 28, color: iconColor),
+    );
+  }
+
+  Widget _buildInfo() {
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Text(
+          document.title,
+          style: const TextStyle(
+            fontSize: 16,
+            fontWeight: FontWeight.w600,
+            color: AppColors.grey900,
+          ),
+        ),
+        const SizedBox(height: 4),
+        Row(
+          children: [
+            const Icon(
+              Icons.calendar_today,
+              size: 13,
+              color: AppColors.grey500,
+            ),
+            const SizedBox(width: 4),
+            Text(
+              document.formattedDateWithPrefix,
+              style: const TextStyle(fontSize: 13, color: AppColors.grey500),
+            ),
+            if (document.fileSize != null) ...[
+              const SizedBox(width: 8),
+              const Text(
+                '•',
+                style: TextStyle(fontSize: 13, color: AppColors.grey500),
+              ),
+              const SizedBox(width: 8),
+              Text(
+                document.fileSize!,
+                style: const TextStyle(fontSize: 13, color: AppColors.grey500),
+              ),
+            ],
+          ],
+        ),
+        const SizedBox(height: 6),
+        Text(
+          document.description,
+          style: const TextStyle(
+            fontSize: 14,
+            color: AppColors.grey500,
+            height: 1.4,
+          ),
+          maxLines: 2,
+          overflow: TextOverflow.ellipsis,
+        ),
+      ],
+    );
+  }
+
+  Widget _buildDownloadButton() {
+    return ElevatedButton.icon(
+      onPressed: onDownload,
+      style: ElevatedButton.styleFrom(
+        backgroundColor: AppColors.primaryBlue,
+        foregroundColor: AppColors.white,
+        elevation: 0,
+        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
+        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
+      ),
+      icon: const Icon(Icons.download, size: 18),
+      label: const Text(
+        'Tải về',
+        style: TextStyle(fontSize: 14, fontWeight: FontWeight.w500),
+      ),
+    );
+  }
+}