* {
    margin: 0;
    padding: 0;
}

.focus {
    overflow: hidden;
    position: relative;
    width: 1370px;
    height: 500px;
    margin: 0 auto;
}

li {
    list-style: none;
}

#slide {
    position: absolute;
    left: 0;
    top: 0;
    /* 总宽度调整为 1370 * 5 = 6850px (4图+1克隆) */
    width: 6850px;
    height: 500px;
}

#slide li {
    float: left;
    width: 1370px;
    height: 500px;
}

#slide li img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

ol {
    position: absolute;
    padding: 0 15px;
    height: 20px;
    bottom: 0px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 10px;
    /* background-color: rgba(0, 0, 0, .3); */
}

.left {
    display: none;
    position: absolute;
    border-radius: 50%;
    left: 40px;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
}

.left img {
    width: 50px;
    height: 50px;
}

.right {
    display: none;
    position: absolute;
    right: 40px;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
}

.right img {
    width: 50px;
    height: 50px;
}

ol li {
    float: left;
    width: 55px;
    height: 4px;
    margin-right: 9px;
    background-color: rgba(0, 0, 0, .3);
}

ol li:last-child {
    margin-right: 0;
}

.current {
    background-color: #fff;
}