pseudoBeforeStyle property
      
      CSSStyleDeclaration?
      get
      pseudoBeforeStyle
      
    
    
    
Implementation
CSSStyleDeclaration? get pseudoBeforeStyle => _pseudoBeforeStyle;
      
      set
      pseudoBeforeStyle
      (CSSStyleDeclaration? newStyle) 
      
    
    
    
Implementation
set pseudoBeforeStyle(CSSStyleDeclaration? newStyle) {
  _pseudoBeforeStyle = newStyle;
  target?.markBeforePseudoElementNeedsUpdate();
}