.banner{
    width: 100%;
    height: 400px;
    background-image: url("../img/about-bg.png");
    background-size: cover;
    text-align: center;
    color: #fff;
    overflow: hidden;
}
.banner h2{
    margin-top: 160px;
    font-size: 32px;
    margin-bottom: 40px;
}
.banner p{
    margin-top: 10px;
    font-size: 20px;
}
.title{
    text-align: center;
    font-size: 30px;
    font-weight: 400;
}
.part1{
    overflow: hidden;
}
.part1 h2 {
    margin-top: 60px;
}
.p1{
    margin-top: 30px;
    display: flex;
    justify-content: space-around;
    align-items: center;
}
.p1-img{
    width: 500px;
}
.p1-img img{
    width: 500px;
}
.p1 p {
    width: 650px;
    font-size: 16px;
    line-height: 1.8;
}
.part2{
    margin-top: 40px;
    height: 350px;
    background-color: #f2f2f2;
    overflow: hidden;
}
.part2 h2 {
    margin-top: 50px;
}
.p2-item {
    width: 400px;
    height: 180px;
    background-color: #fff;
    text-align: center;
    overflow: hidden;
    padding: 10px;
    margin-top: 30px;
}
.p2-item h2 {
    margin-top: 16px;
    font-size: 22px;
}
.p2-item p{
    font-size: 16px;
    margin-top: 10px;
}
.p2{
    display: flex;
    justify-content: space-around;
}
.p3-img{
    display: flex;
    justify-content: center;
    margin-top: 30px;
}
.p3-img img {
    width: 1200px;
}
.part3 h2 {
    margin-top: 40px;
}
.part4{
    overflow: hidden;
    margin-top: 60px;
    background-color: #f2f2f2;
    height: 500px;
}
.part4 h2 {
    margin-top: 40px;
}
.p4{
    display: flex;
    justify-content: space-around;
    align-items: center;
}
.p4 p {
    width: 550px;
    line-height: 1.8;
    font-size: 16px;
}