:root { font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif; color: #272935; }
* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }
body { display: flex; flex-direction: column; height: 100dvh; overflow: hidden; }
.demo-frame { display: block; width: 100%; flex: 1; min-height: 0; border: 0; background: #fff; }