iview/src/styles/animation/index.less

.motion-common() {
    animation-duration: @animation-time;
    animation-fill-mode: both;
}

.make-motion(@className, @keyframeName) {
    .@{className}-enter-active, .@{className}-appear {
        .motion-common();
        animation-play-state: paused;
    }
    .@{className}-leave-active {
        .motion-common();
        animation-play-state: paused;
    }
    .@{className}-enter-active, .@{className}-appear {
        animation-name: ~"@{keyframeName}In";
        animation-play-state: running;
    }
    .@{className}-leave-active {
        animation-name: ~"@{keyframeName}Out";
        animation-play-state: running;
    }
}

@import "fade";
@import "move";
@import "ease";
@import "slide";

.collapse-transition {
    transition: @transition-time height ease-in-out, @transition-time padding-top ease-in-out, @transition-time padding-bottom ease-in-out;
}