Tinble: Now with a dark theme

Although I don't care much for dark themes, I've added a simple dark theme to Tinble anyway. It was just a matter of adding the following to the styles.css file, after all:

@media (prefers-color-scheme: dark) {
  :root {
    --body-bg: #000000;
    --body-color: #b3b3b3;
  }
}

@media (prefers-color-scheme: light) {
  :root {
    --body-bg: #f2f2f2;
    --body-color: black;
  }
}

body {
  background: var(--body-bg);
  color: var(--body-color);
}

It's nothing fancy, but it does the job.