hi! i don't know how much you know, so here's a basic overview (if you need more help lmk and i'll get back to you next time im on my laptop lol):

the wormy is made out of sections of two different basic types, the horizontal and the vertical ones. the vertical ones are just purple boxes. and the horizontal ones... are also just purple boxes! the difference is that the horizontal ones use the border-radius property to give it a rounded look.

i'm using a shorthand version of the border-radius property that lets you edit all four corners in a single line-- 0px means no rounding at all, for example. if you change the order of the numbers, opposite corners will be reversed, so the worm will be "flipped"! i recommend trying it on a site like th.circlejourney.net/ so you can see your changes live and play around with it.

the darker purple segment is also just a purple box with rounded corners. i'm on my phone now so checking exactly what change to make isn't convenient, but if you switch a right to a left or some numbers around or something it should switch to the other side, i'm not entirely sure. be sure to check how it looks on different screen sizes (you can do this on circlejourney easily by using the vertical layout & making the code input larger or smaller) to make sure it stays in place right.

like i said, let me know if you need any help with that!