feat: support custom class

src/rough-notation.ts

@@ -74,7 +74,7 @@ class RoughAnnotationImpl implements RoughAnnotation {
     if (this._state === 'unattached' && this._e.parentElement) {
       ensureKeyframes();
       const svg = this._svg = document.createElementNS(SVG_NS, 'svg');
-      svg.setAttribute('class', 'rough-annotation');
+      svg.setAttribute('class', ['rough-annotation', this._config.class || ''].filter(Boolean).join(' '));
       const style = svg.style;
       style.position = 'absolute';
       style.top = '0';

src/types.ts

@@ -24,6 +24,8 @@ export interface RoughAnnotationConfigBase {
   padding?: RoughPadding; // defaults to 5px
   iterations?: number; // defaults to 2
   brackets?: BracketType | BracketType[]; // defaults to 'right'
+  // Additional class added to the annotation
+  class?: string
 }
 
 export interface RoughAnnotation extends RoughAnnotationConfigBase {