@keyframes tonext {
    75% { left: 0; }
    95% { left: 100%; }
    98% { left: 100%; }
    99% { left: 0; }
}
@keyframes tostart {
    75% { left: 0; }
    95% { left: -300%; }
    98% { left: -300%; }
    99% { left: 0; }
}
@keyframes snap {
    96% { scroll-snap-align: center; }
    97% { scroll-snap-align: none; }
    99% { scroll-snap-align: none; }
    100% { scroll-snap-align: center; }
}
#pics {
    box-sizing: border-box;
}
#pics ol, #pics li {
    border-radius: 10px;
    list-style: none;
    margin: 0;
    padding: 0;
}
.slider {
    position: relative;
    padding-top: 800px;
    filter: drop-shadow(0 0 5px rgba(0,0,0,0.1));
    perspective: 100px;
    counter-reset: frameNum;
}
.slider_viewport {
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    display: flex;
    overflow-x: scroll;
    scroll-behavior: smooth;
    scroll-snap-type: x mandatory;
}
.slider_slide {
    position: relative;
    flex: 0 0 100%;
    width: 100%;
    background-color: #000000;
    counter-increment: frameNum;
    background-repeat: no-repeat;
    background-position: center center;
    background-size: contain;
}
.slider_slide:before {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate3d(-50%,-40%,70px);
    color: #FFFFFF;
}
.slider_snapper {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    scroll-snap-align: center;
}
.slider_nav {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    text-align: center;
}
.slider_nav_list, .slider_nav_item {
    display: inline-block;
}
.slider_nav_button {
    display: inline-block;
    width: 1.5rem;
    height: 1.5rem;
    background-color: #333333;
    background-clip: content-box;
    border: 0.25rem solid transparent;
    border-radius: 50%;
    font-size: 0;
    transition: transform 0.1s;
}
.slider::before, .slider::after, .slider_prev, .slider_next {
    position: absolute;
    top: 50%;
    width: 3.75rem;
    height: 3.75rem;
    transform: translateY(-50%);
    border-radius: 50%;
    font-size: 0;
    outline: 0;
}
.slider::before, .slider_prev {
    left: 3px;
}
.slider::after, .slider_next {
    right: 3px;
}
.slider::before, .slider::after {
    content: '';
    z-index: 1;
    background-color: #333333;
    background-size: 1.5rem 1.5rem;
    background-repeat: no-repeat;
    background-position: center center;
    color: #FFFFFF;
    font-size: 2.5rem;
    line-height: 4rem;
    text-align: center;
    pointer-events: none;
}
.slider::before {
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpolygon points='0,50 80,100 80,0' fill='%23fff'/%3E%3C/svg%3E");
}
.slider::after {
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpolygon points='100,50 20,100 20,0' fill='%23fff'/%3E%3C/svg%3E");
}