p]:inline” data-streamdown=”list-item”>Pianeta Sostenibile: Idee per un Futuro Verde

Those are CSS custom properties (CSS variables) used by a system—likely a design/animation toolkit—to control an element’s animation. Brief breakdown:

• -sd-animation: sd-fadeIn;
  • Purpose: names which animation to apply (here: a predefined “sd-fadeIn” keyframes animation).
• –sd-duration: 0ms;
  • Purpose: sets the animation duration. 0ms means the animation runs instantly (no visible transition).
• –sd-easing: ease-in;
  • Purpose: sets the easing/timing function for the animation (controls acceleration curve).

Example usage in CSS:

.element {–sd-animation: sd-fadeIn;  –sd-duration: 300ms;  –sd-easing: ease-in;  animation: var(–sd-animation) var(–sd-duration) var(–sd-easing);}@keyframes sd-fadeIn {  from { opacity: 0; transform: translateY(6px); }  to   { opacity: 1; transform: translateY(0); }}

Notes:

• With –sd-duration: 0ms the animation is effectively disabled; set a nonzero duration (e.g., 200–400ms) to see the effect.