Open any loader, copy the HTML into your markup and the CSS into your stylesheet. Nothing else is required: no JavaScript, no icon fonts, no image files. Each loader's classes are prefixed with its own name so several can share a page.
To change the color, set --ldr-color on the loader or any ancestor. To change the size, set --ldr-size. Everything inside scales from those two values, so a 16px inline spinner and a 96px page loader are the same snippet.
Every snippet ships with a prefers-reduced-motion rule that slows the animation for people who have asked their OS for less motion. Keep it.