Add custom font styles and theme enhancements

- Created a new CSS file for font imports and defined font families for base, mono, strong, em, and h1 elements.
- Added a new JavaScript file to extend the default VitePress theme, incorporating a custom layout and a Vue component for enhanced functionality.
- Integrated Mermaid diagram support and included the necessary styles for it.

.obsidian/plugins/odox/styles.css

@@ -0,0 +1,30 @@
+/*
+
+This CSS file will be included with your plugin, and
+available in the app when your plugin is enabled.
+
+If your plugin does not need CSS, delete this file.
+
+*/
+
+/* 透明导出模式：隐藏洞洞板背景 */
+.canvas-transparent-export .canvas-background {
+	display: none !important;
+}
+
+/* 透明导出模式：确保 canvas 容器背景透明 */
+.canvas-transparent-export {
+	background-color: transparent !important;
+	background-image: none !important;
+}
+
+/* 截图时隐藏页面其他元素 */
+.odox-hidden {
+	display: none !important;
+}
+
+/* 截图时的 body 样式 */
+.odox-capturing {
+	background-color: transparent !important;
+	background-image: none !important;
+}