These figures can be made remarkably small in bytes and so load very fast. No long paragraphs presenting large blocks of type. I find those very hard to read. The background colors and images were were picked not to be overly distracting. I've avoided red type on a black background and similar avant-garde arrangements.
Monitors differ on how they display color.
What looks good to me might not look good to you. Nevertheless, your milage may vary. Monitors differ on resolution. I've tried to keep enough information at the top of the screen as possible so that the user can decide whether or not to look at the rest. This has not always been possible.