The landing page is difficult to read due to the strong red background.
Typically white text works better on red.
Green, yellow, red or whatever hue is fine, as long as it's dark or light enough. Colorblind and non-colorblind people can see how dark or light a color is (luminance), but they might not agree on the hue. That's why WCAG contrast checks require luminance contrast and not hue contrast.
It's best to use a contrast checker because it's not always intuitive how dark or light a color is e.g. yellow and lime are almost as light as white.