Responsiveness Check Test how a website's layout responds to viewport width changes. Resizes through breakpoints in a single browser session, screenshots each width, compares adjacent sizes, and reports where layouts break. What this tests : Layout responsiveness — overflow, stacking, navigation transitions, content reflow. What this does NOT test : General accessibility (ARIA, semantic HTML, heading hierarchy, colour contrast). Those don't vary by viewport width — use the ux-audit skill instead. Browser Tool Priority Before starting, detect available browser tools: 1. playwright-cli (preferr…