Untitled

code for the video

Grid: simple
.gallery-grid-item img

Grid: strips
.gallery-strips-item img

Grid: masonry
.gallery-masonry-item img

Slideshow: simple
.gallery-slideshow-item img

Slideshow: full
.gallery-fullscreen-slideshow-item img

Slideshow: reel
.gallery-reel-item img

Here is the main code from the tutorial:

.gallery-grid-item img{
filter:grayscale (1) blur (2px);

}

.gallery-grid-item img:hover{
filter: grayscale (0)
}