list-inside list-decimal whitespace-normal [li_&]:pl-6

Those look like CSS custom properties used by a design system or animation utility. Briefly:

• –sd-animation: sd-fadeIn;
  • Purpose: Names the animation to apply (likely a keyframe set called “sd-fadeIn”).
  • Usage: Consumed by a rule that maps this name to a keyframes animation or toggles a class/animation.
• –sd-duration: 250ms;
  • Purpose: Sets the animation duration to 250 milliseconds.
  • Usage: Typically used with the animation-duration or transition-duration property: animation-duration: var(–sd-duration);
• –sd-easing: ease-in;
  • Purpose: Defines the timing function (easing) for the animation.
  • Usage: Used with animation-timing-function or transition-timing-function: animation-timing-function: var(–sd-easing);

Example CSS showing how they might be used:

:root {–sd-animation: sd-fadeIn;  –sd-duration: 250ms;  –sd-easing: ease-in;}
/* keyframes for sd-fadeIn /@keyframes sd-fadeIn {  from { opacity: 0; transform: translateY(6px); }  to   { opacity: 1; transform: translateY(0); }}
/ utility that applies the named animation */.sd-animated {  animation-name: var(–sd-animation);  animation-duration: var(–sd-duration);  animation-timing-function: var(–sd-easing);  animation-fill-mode: both;}

Notes:

• p]:inline” data-streamdown=“list-item”>You can override these custom properties on elements to vary animation per-component.