CSS :current

The :current pseudo-class is intended for sequential navigation contexts, such as the currently displayed item. It is not widely interoperable for normal production UI.

Syntax

selector:current {
  /* experimental */
}

Reliable pattern

.slide.is-current {
  opacity: 1;
  outline: 0.2rem solid #2563eb;
}

.slide {
  opacity: 0.45;
}

Result:

Use a class such as .is-current when you need reliable current-state styling today.

Important note

Keep :current as a reference topic, but prefer explicit classes or ARIA state attributes for real components.