Digital transformation in higher education has encouraged the use of web-based learning media that can integrate teaching materials, learning activities, and evaluation in a single accessible platform. This study aimed to develop PhytoAction, a Wix-based website employing the Problem-Based Learning (PBL) model integrated with Sustainable Development Goals (SDGs) 13: Climate Action, for the Plant Physiology course. The research followed the Lee and Owens (2004) five-stage development model consisting of analysis, design, development, implementation, and evaluation. Data were collected through validation sheets completed by material experts, media experts, and education practitioners, as well as student response questionnaires during one-to-one, small-group, and field trials. Results showed that the website obtained a "very valid" category from material experts (96.22% before revision, improving to 100% after revision), media experts (92.75% before revision, improving to 96% after revision), and practitioners (97.38%). Practicality trials also indicated a "very practical" category, with average scores of 91.52% (one-to-one trial), 90.06% (small-group trial), and 87.03% (field trial). These findings suggest that PhytoAction is a valid and practical learning medium that can support more contextual, flexible, and student-centered learning in the Plant Physiology course.