This study explores the application of Generative Artificial Intelligence (GAI) in digital interface design, with a focus on human-AI co-creation. By analyzing the tool Midjourney, the study evaluates the AI’s ability to generate visual interfaces from textual prompts and identifies the main benefits and challenges of this approach. GAI democratizes creative design and digital marketing strategies, allowing professionals with varying levels of experience to experiment with automated visual content generation. However, the effectiveness of these tools heavily relies on the accuracy of the provided prompts, highlighting the importance of prompt engineering as a critical skill for optimizing generated outcomes. The research employed a practical case study to create an e-commerce homepage, examining the creative capabilities and limitations of GAI tools. While AI proved effective in generating initial visual solutions, challenges arose regarding the coherence and accuracy of the outputs. The study concludes with practical recommendations on how to efficiently integrate GAI into design workflows, emphasizing the transformative potential of these technologies, alongside the limitations that still need to be addressed.