2. The method of claim 1 , the method further comprising: in response to obtaining first input indicating a first point along the first timeline, displaying a first keyframe indicator on the first timeline at the first point; wherein the first keyframe indicator represents a first keyframe of the style sheet animation; wherein the first point corresponds to a first time during the style sheet animation; in response to obtaining second input indicating a second point along the first timeline, displaying a second keyframe indicator on the first timeline at the second point; wherein the second keyframe indicator represents a second keyframe of the style sheet animation; wherein the second point corresponds to a second time during the style sheet animation; wherein generating the style sheet language text further comprises generating style sheet language text that declares the first and second keyframes and that reflects an association between the first keyframe and the first time and an association between the second keyframe and the second time.
4. The method of claim 2 , further comprising: in response to obtaining the first input, associating the first keyframe with a default easing function.