fix: 将面包屑样式移至全局 SCSS 文件

移除内联 style 标签（可能被 CSP 阻止），
使用 CSS 变量确保主题一致性

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: Digidai

_includes/breadcrumb.html

@@ -49,57 +49,4 @@
       {%- endfor -%}
     </ol>
   </nav>
-
-  <style>
-    .breadcrumb-nav {
-      padding: 1rem 0;
-      margin-bottom: 1rem;
-      border-bottom: 1px solid #e5e7eb;
-    }
-
-    .breadcrumb-list {
-      display: flex;
-      flex-wrap: wrap;
-      list-style: none;
-      margin: 0;
-      padding: 0;
-      gap: 0.5rem;
-    }
-
-    .breadcrumb-item {
-      display: flex;
-      align-items: center;
-      font-size: 0.875rem;
-      color: #6b7280;
-    }
-
-    .breadcrumb-item a {
-      color: #2563eb;
-      text-decoration: none;
-      transition: color 0.2s;
-    }
-
-    .breadcrumb-item a:hover {
-      color: #1d4ed8;
-      text-decoration: underline;
-    }
-
-    .breadcrumb-item:not(:last-child)::after {
-      content: '/';
-      margin-left: 0.5rem;
-      color: #9ca3af;
-    }
-
-    .breadcrumb-item:last-child {
-      color: #1f2937;
-      font-weight: 500;
-    }
-
-    @media (max-width: 640px) {
-      .breadcrumb-nav {
-        padding: 0.75rem 0;
-        font-size: 0.8125rem;
-      }
-    }
-  </style>
 {%- endif -%}

_sass/_components.scss

@@ -93,6 +93,51 @@
     margin-top: 16px;
 }
 
+// Breadcrumb Navigation
+.breadcrumb-nav {
+    padding: 16px 0;
+    margin-bottom: 16px;
+    border-bottom: 1px solid var(--divider-color);
+}
+
+.breadcrumb-list {
+    display: flex;
+    flex-wrap: wrap;
+    list-style: none;
+    margin: 0;
+    padding: 0;
+    gap: 8px;
+}
+
+.breadcrumb-item {
+    display: flex;
+    align-items: center;
+    font-size: 14px;
+    color: var(--text-secondary);
+
+    a {
+        color: var(--accent-color);
+        text-decoration: none;
+        transition: color var(--transition);
+
+        &:hover {
+            color: var(--text-primary);
+            text-decoration: underline;
+        }
+    }
+
+    &:not(:last-child)::after {
+        content: '/';
+        margin-left: 8px;
+        color: var(--text-tertiary);
+    }
+
+    &:last-child {
+        color: var(--text-primary);
+        font-weight: 500;
+    }
+}
+
 // Buttons
 .btn {
     display: inline-flex;