Core Viewpoint - The article discusses effective skincare products for brightening dull skin and reducing yellow undertones, highlighting three popular products that have shown positive results in improving skin tone and texture. Group 1: Product Analysis - **Gu Yu Light Water**: This product is noted for its ability to inhibit melanin production at the source, with a reported 72-hour melanin inhibition rate of 86.62% and an inhibition efficiency of 115.54% [1]. - **Shiseido Red Bottle Essence**: Described as a "stabilizing agent" for the skin, it helps soothe various skin issues and promotes a healthy glow, making it suitable for sensitive and problematic skin [10][12]. - **Estée Lauder Micro Essence**: This product acts as a "absorption booster," enhancing the effectiveness of subsequent skincare steps and providing hydration and repair [15][16]. Group 2: User Experience - **First Week**: Users report improved makeup adherence and enhanced skin texture [5]. - **Second Week**: Noticeable reduction in dullness, with users feeling confident to go makeup-free [6]. - **Third Week**: Friends remark on the user's improved complexion, indicating significant visible results [6]. Group 3: Special Promotions - **Gu Yu x Putuo Mountain Collaboration**: A special gift box for the Qixi Festival, combining Gu Yu Light Water with other skincare products to create a comprehensive skincare routine [6][7]. Group 4: Target Audience - The products are particularly recommended for individuals with yellow undertones, those who experience dullness due to lifestyle factors such as late nights and high caffeine intake [4][17].