html,
body {
    width: 100%;
    height: auto;
    margin: 0 auto;
}

.over {
    position: relative;
    width: 100%;
    height: 700px;
    background-image: url("第五.jpg");
    filter: brightness(0.5);
    /* 50% 亮度 */
}

.text {
    position: absolute;
    top: 22%;
    left: 50%;
    color: #111;
}

.home {
    position: absolute;
    display: block;
    width: 128px;
    height: 128px;
    right: 0%;
    bottom: 0%;
}