fix: 修复所有页面 Tab 导航下方冗余空白

- 将 body 布局从普通流改为 flex 纵向布局，navbar 和内容区自然排列
- navbar 移除 position:sticky，改为 flex-shrink:0 作为固定头部
- 新增 .main-content 工具类（flex:1; overflow:hidden），替代 calc(100vh-56px)+margin-top 方案
- builder/dashboard 页面使用 main-content 类占满剩余空间
- settings 页面 margin-top 从 80px 调整为 24px

frontend/dashboard.html

@@ -8,7 +8,7 @@
     <link rel="stylesheet" href="/static/common.css">
 </head>
 <body>
-    <div class="flex" style="height: calc(100vh - 56px); margin-top: 56px;">
+    <div class="flex main-content">
         <!-- 左侧项目树 -->
         <div class="w-64 border-r overflow-y-auto p-4" style="border-color: var(--border-color); background: var(--bg-primary);">
             <div class="search-box mb-4">

frontend/index.html

@@ -8,7 +8,7 @@
     <link rel="stylesheet" href="/static/common.css">
 </head>
 <body>
-    <div class="flex" style="height: calc(100vh - 56px); margin-top: 56px;">
+    <div class="flex main-content">
         <!-- 左侧面板 -->
         <div class="w-1/3 border-r overflow-y-auto p-4 flex flex-col gap-4" style="border-color: var(--border-color); background: var(--bg-primary);">
             <!-- 项目/会话 -->
@@ -73,6 +73,17 @@
                 <div class="card-body" id="snippets-container"></div>
             </div>
 
+            <!-- 参考材料 -->
+            <div class="card">
+                <div class="card-header">
+                    📦 参考材料
+                    <button class="btn btn-sm" onclick="addMaterial()">+ 添加</button>
+                </div>
+                <div class="card-body" id="materials-container">
+                    <div class="text-sm text-muted" id="materials-empty">暂无参考材料</div>
+                </div>
+            </div>
+
             <!-- CLAUDE.md -->
             <div class="card">
                 <div class="collapse-header" onclick="toggleCollapse(this)">
@@ -173,6 +184,7 @@
         let allSnippets = [];
         let selectedTags = {}; // tagId -> optionId
         let selectedSnippets = []; // [{snippetId, sortOrder}]
+        let materials = []; // [{title, content}]
         let suggestions = [];
 
         // 初始化
@@ -380,6 +392,16 @@
                 }
             }
 
+            // Materials
+            const validMaterials = materials.filter(m => m.content.trim());
+            if (validMaterials.length > 0) {
+                const materialParts = validMaterials.map((m, i) => {
+                    const title = m.title.trim() || `参考材料${i + 1}`;
+                    return `--- ${title} ---\n${m.content}`;
+                });
+                parts.push(`## 参考材料\n\n${materialParts.join('\n\n')}`);
+            }
+
             // Suggestions
             const adoptedSuggestions = suggestions.filter(s => s.adopted);
             if (adoptedSuggestions.length > 0) {
@@ -441,6 +463,51 @@
         document.getElementById('tag-search')?.addEventListener('input', debounce(() => renderTags(), 300));
         document.getElementById('snippet-search')?.addEventListener('input', debounce(() => renderSnippets(), 300));
 
+        // 参考材料管理
+        function addMaterial() {
+            materials.push({ title: '', content: '' });
+            renderMaterials();
+            updatePreview();
+        }
+
+        function removeMaterial(index) {
+            materials.splice(index, 1);
+            renderMaterials();
+            updatePreview();
+        }
+
+        function renderMaterials() {
+            const container = document.getElementById('materials-container');
+            const emptyHint = document.getElementById('materials-empty');
+
+            if (materials.length === 0) {
+                container.innerHTML = '<div class="text-sm text-muted" id="materials-empty">暂无参考材料</div>';
+                return;
+            }
+
+            container.innerHTML = materials.map((m, i) => `
+                <div class="mb-3 p-3" style="background:var(--bg-tertiary);border-radius:8px">
+                    <div class="flex items-center justify-between mb-2">
+                        <input class="input" placeholder="参考材料${i + 1}" value="${escapeHtml(m.title)}"
+                            oninput="updateMaterialTitle(${i}, this.value)" style="flex:1;margin-right:8px">
+                        <button class="btn btn-sm" onclick="removeMaterial(${i})" style="color:var(--error-color)">✕</button>
+                    </div>
+                    <textarea class="textarea" placeholder="输入参考材料内容..." rows="3"
+                        oninput="updateMaterialContent(${i}, this.value)">${escapeHtml(m.content)}</textarea>
+                </div>
+            `).join('');
+        }
+
+        function updateMaterialTitle(index, title) {
+            materials[index].title = title;
+            updatePreview();
+        }
+
+        function updateMaterialContent(index, content) {
+            materials[index].content = content;
+            updatePreview();
+        }
+
         // 自定义输入变化时更新预览
         document.getElementById('custom-content')?.addEventListener('input', debounce(() => updatePreview(), 200));
         document.getElementById('project-name')?.addEventListener('input', debounce(() => updatePreview(), 200));
@@ -591,6 +658,14 @@
                 sort_order: s.sortOrder
             }));
 
+            const materialsData = materials
+                .filter(m => m.content.trim())
+                .map((m, i) => ({
+                    title: m.title.trim(),
+                    content: m.content,
+                    sort_order: i
+                }));
+
             try {
                 await API.post('/api/builder/sessions', {
                     title,
@@ -598,7 +673,8 @@
                     final_prompt: finalPrompt,
                     claude_session_id: claudeSessionId,
                     tag_option_ids: tagOptionIds,
-                    snippet_ids: snippetIds
+                    snippet_ids: snippetIds,
+                    materials: materialsData
                 });
                 closeSaveModal();
                 Toast.success('会话已保存');
@@ -616,6 +692,7 @@
                     claudeMD: document.getElementById('claude-md').value,
                     selectedTags: { ...selectedTags },
                     selectedSnippets: [...selectedSnippets],
+                    materials: materials.map(m => ({ title: m.title, content: m.content })),
                 });
             }, 1000);
 
@@ -633,6 +710,8 @@
             document.getElementById('claude-md').value = draft.claudeMD || '';
             selectedTags = draft.selectedTags || {};
             selectedSnippets = draft.selectedSnippets || [];
+            materials = draft.materials || [];
+            renderMaterials();
         }
 
         function resetBuilder() {
@@ -644,11 +723,13 @@
             document.getElementById('session-prompts').classList.add('hidden');
             selectedTags = {};
             selectedSnippets = [];
+            materials = [];
             suggestions = [];
             document.getElementById('suggestions-card').style.display = 'none';
             Draft.clear('builder');
             renderTags();
             renderSnippets();
+            renderMaterials();
             updatePreview();
             Toast.success('已重置');
         }

frontend/settings.html

@@ -8,7 +8,7 @@
     <link rel="stylesheet" href="/static/common.css">
 </head>
 <body>
-    <div style="max-width:640px;margin:80px auto 0;padding:0 24px">
+    <div style="max-width:640px;margin:24px auto 0;padding:0 24px">
         <h1 style="font-size:24px;font-weight:700;margin-bottom:24px">⚙️ 设置</h1>
 
         <!-- LLM 配置 -->

frontend/static/common.css

@@ -39,10 +39,16 @@
     padding: 0;
 }
 
+html, body {
+    height: 100%;
+}
+
 body {
     font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
     background: var(--bg-secondary);
     color: var(--text-primary);
+    display: flex;
+    flex-direction: column;
     min-height: 100vh;
 }
 
@@ -55,12 +61,17 @@ body {
     display: flex;
     align-items: center;
     justify-content: space-between;
-    position: sticky;
-    top: 0;
+    flex-shrink: 0;
     z-index: 100;
     box-shadow: var(--shadow-sm);
 }
 
+/* 主内容区 */
+.main-content {
+    flex: 1;
+    overflow: hidden;
+}
+
 .nav-brand {
     font-size: 18px;
     font-weight: 700;

internal/db/db.go

@@ -102,6 +102,16 @@ func AutoMigrate() error {
 			PRIMARY KEY (id),
 			KEY idx_session_id (builder_session_id)
 		) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4`,
+
+		`CREATE TABLE IF NOT EXISTS builder_session_materials (
+			id bigint NOT NULL AUTO_INCREMENT,
+			builder_session_id bigint NOT NULL,
+			title varchar(255) NOT NULL DEFAULT '',
+			content text NOT NULL,
+			sort_order int NOT NULL DEFAULT 0,
+			PRIMARY KEY (id),
+			KEY idx_session_id (builder_session_id)
+		) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4`,
 	}
 
 	for _, ddl := range tables {

internal/handlers/builder.go

@@ -47,6 +47,11 @@ func CreateBuilderSession(w http.ResponseWriter, r *http.Request) {
 			SnippetID int64 `json:"snippet_id"`
 			SortOrder int   `json:"sort_order"`
 		} `json:"snippet_ids"`
+		Materials []struct {
+			Title    string `json:"title"`
+			Content  string `json:"content"`
+			SortOrder int   `json:"sort_order"`
+		} `json:"materials"`
 	}
 	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
 		fail(w, 400, "请求格式错误")
@@ -79,6 +84,12 @@ func CreateBuilderSession(w http.ResponseWriter, r *http.Request) {
 			sessionID, s.SnippetID, s.SortOrder)
 	}
 
+	// Insert materials
+	for _, m := range req.Materials {
+		db.DB.Exec("INSERT INTO builder_session_materials (builder_session_id, title, content, sort_order) VALUES (?, ?, ?, ?)",
+			sessionID, m.Title, m.Content, m.SortOrder)
+	}
+
 	success(w, map[string]int64{"id": sessionID})
 }
 
@@ -121,12 +132,27 @@ func GetBuilderSession(w http.ResponseWriter, r *http.Request) {
 		snippetRows.Close()
 	}
 
+	// Load materials
+	materialRows, err := db.DB.Query("SELECT id, builder_session_id, title, content, sort_order FROM builder_session_materials WHERE builder_session_id=? ORDER BY sort_order", id)
+	if err == nil {
+		for materialRows.Next() {
+			var m models.SessionMaterial
+			if err := materialRows.Scan(&m.ID, &m.BuilderSessionID, &m.Title, &m.Content, &m.SortOrder); err == nil {
+				s.Materials = append(s.Materials, m)
+			}
+		}
+		materialRows.Close()
+	}
+
 	if s.Tags == nil {
 		s.Tags = []models.SessionTag{}
 	}
 	if s.Snippets == nil {
 		s.Snippets = []models.SessionSnippet{}
 	}
+	if s.Materials == nil {
+		s.Materials = []models.SessionMaterial{}
+	}
 
 	success(w, s)
 }
@@ -151,6 +177,11 @@ func UpdateBuilderSession(w http.ResponseWriter, r *http.Request) {
 			SnippetID int64 `json:"snippet_id"`
 			SortOrder int   `json:"sort_order"`
 		} `json:"snippet_ids"`
+		Materials []struct {
+			Title    string `json:"title"`
+			Content  string `json:"content"`
+			SortOrder int   `json:"sort_order"`
+		} `json:"materials"`
 	}
 	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
 		fail(w, 400, "请求格式错误")
@@ -183,6 +214,13 @@ func UpdateBuilderSession(w http.ResponseWriter, r *http.Request) {
 			id, s.SnippetID, s.SortOrder)
 	}
 
+	// Replace materials
+	db.DB.Exec("DELETE FROM builder_session_materials WHERE builder_session_id=?", id)
+	for _, m := range req.Materials {
+		db.DB.Exec("INSERT INTO builder_session_materials (builder_session_id, title, content, sort_order) VALUES (?, ?, ?, ?)",
+			id, m.Title, m.Content, m.SortOrder)
+	}
+
 	success(w, nil)
 }
 
@@ -195,12 +233,13 @@ func DeleteBuilderSession(w http.ResponseWriter, r *http.Request) {
 
 	db.DB.Exec("DELETE FROM builder_session_tags WHERE builder_session_id=?", id)
 	db.DB.Exec("DELETE FROM builder_session_snippets WHERE builder_session_id=?", id)
+	db.DB.Exec("DELETE FROM builder_session_materials WHERE builder_session_id=?", id)
 	db.DB.Exec("DELETE FROM builder_sessions WHERE id=?", id)
 	success(w, nil)
 }
 
 // AssemblePrompt 组装最终 Prompt
-func AssemblePrompt(projectName string, customContent string, tagOptions []models.TagOption, snippets []models.Snippet, suggestions []string) string {
+func AssemblePrompt(projectName string, customContent string, tagOptions []models.TagOption, snippets []models.Snippet, suggestions []string, materials []models.SessionMaterial) string {
 	var parts []string
 
 	// Project context
@@ -231,6 +270,19 @@ func AssemblePrompt(projectName string, customContent string, tagOptions []model
 		parts = append(parts, fmt.Sprintf("## 参考片段\n\n%s", strings.Join(snippetParts, "\n\n")))
 	}
 
+	// Materials
+	if len(materials) > 0 {
+		var materialParts []string
+		for i, m := range materials {
+			title := m.Title
+			if title == "" {
+				title = fmt.Sprintf("参考材料%d", i+1)
+			}
+			materialParts = append(materialParts, fmt.Sprintf("--- %s ---\n%s", title, m.Content))
+		}
+		parts = append(parts, fmt.Sprintf("## 参考材料\n\n%s", strings.Join(materialParts, "\n\n")))
+	}
+
 	// Suggestions
 	if len(suggestions) > 0 {
 		parts = append(parts, fmt.Sprintf("## 补充建议\n\n%s", strings.Join(suggestions, "\n")))

internal/models/models.go

@@ -43,6 +43,7 @@ type BuilderSession struct {
 	UpdatedAt       time.Time `json:"updated_at"`
 	Tags            []SessionTag     `json:"tags,omitempty"`
 	Snippets        []SessionSnippet `json:"snippets,omitempty"`
+	Materials       []SessionMaterial `json:"materials,omitempty"`
 }
 
 // SessionTag 构建会话标签关联
@@ -61,6 +62,15 @@ type SessionSnippet struct {
 	SortOrder       int   `json:"sort_order"`
 }
 
+// SessionMaterial 构建会话参考材料
+type SessionMaterial struct {
+	ID              int64  `json:"id"`
+	BuilderSessionID int64 `json:"builder_session_id"`
+	Title           string `json:"title"`
+	Content         string `json:"content"`
+	SortOrder       int    `json:"sort_order"`
+}
+
 // Prompt prompts 表记录（只读）
 type Prompt struct {
 	ID          int64     `json:"id"`