*{
	margin: 0;
	padding: 0;
	list-style-type: none;
}

.contain{
	width: 100%;
}

/* 导航 */
.head{
	position: absolute;
	top: 0;
	width: 100%;
	height: 70px;
	line-height: 70px;
	z-index: 999;
}

.head-contain{
	display: flex;
	margin: auto;
	width: 70%;
}

.head-contain ul{
	display: flex;
	margin-left: auto;
	width: 30%;
	justify-content: space-around;
}

.head-contain ul li a{
	color: #fff;
}

/* 期待来信 */
.expect{
	background: url('../img/留资背景.jpg') no-repeat center center;
	background-size: cover;
	width: 100%;
	height: 600px;
	padding-top: 150px;
}

.expect_zong{
	width: 70%;
	margin: auto;
}

.expect_zong_title{
	color: #fff;
	text-align: center;
}

.expect_zong_title p{
	margin-top: 20px;
	margin-bottom: 30px;
	font-size: 12px;
}

.expect_zong__second{
	display: flex;
	justify-content: space-around;
}

.expect_zong_form{
	display: flex;
	flex-direction: column;
	justify-content: center;
	align-items: center;
}

.expect_zong_form_first{
	display: flex;
}

.expect_zong_form_first input{
	width: 200px;
	height: 40px;
	line-height: 40px;
}

.expect_zong_form_first input:first-child{
	margin-right: 20px;
}

.expect_zong_form button{
	width: 150px;
	height: 40px;
	line-height: 40px;
	color: #fff;
	background-color: #053c96;
	border: none;
	margin: 20px 0 0;
}

.expect_zong_second__contact{
	background-color: #fff;
	height: 173px;
	border-radius: 5px;
	padding: 20px;
	text-align: center;
	display: flex;
	flex-direction: column;
	justify-content: space-around;
	font-size: 15px;
}

.expect_zong_second__contact div:first-child{
	font-weight: bold;
}

/* 核心业务 */
.core-business{
	background: url('../img/核心业务背景.jpg') no-repeat center center;
	background-size: cover;
	width: 100%;
	height: 790px;
	padding-top: 5%;
}

.core-business-title{
	width: 70%;
	margin: auto;
	color: #fff;
}

.core-business-title p{
	margin-bottom: 5px;
	font-size: 10px;
}

.core-business-title h3{
	margin: 0;
	margin-bottom: 15px;
	font-weight: bold;
}

.core-business-content{
	display: flex;
	width: 70%;
	margin: auto;
	gap: 20px;
	margin-top: 100px;
}

.core-business-content__first{
	width: 300px;
	height: 450px;
	text-align: center;
	background-color: #fff;
	border-radius: 10px;
	position: relative;
}

.core-business-content__first img{
	margin: 50px auto 40px;
}

.core-business-content__first p{
	margin: 0 20px;
}

.core-business-content__first h4{
	font-weight: bold;
	margin-bottom: 40px;
}

.core-business-content__first div{
	height: 50px;
	display: flex;
	justify-content: center;
	align-items: center;
	position: absolute;
	bottom: 30px;
	left: 35%;
}

.core-business-content__first div a{
	color: #2c2c2c;
	display: block;
	border-bottom: 1px solid #2c2c2c;
	text-decoration: none;
}

.core-business-content__first div img{
	margin: 0;
}

/* 工程案例 */
.engineering{
	background: url('../img/工程案例背景.jpg') no-repeat center center;
	background-size: cover;
	width: 100%;
	height: 910px;
	padding-top: 60px;
}

.engineering_zong{
	width: 70%;
	margin: auto;
}

.engineering_zong_title p{
	font-size: 9px;
	margin: 0;
}

.engineering_zong_title h3{
	margin-top: 3px;
	font-weight: bold;
}

.engineering_zong_content{
	display: flex;
	justify-content: space-between;
	margin-top: 50px;
}

.engineering_zong_content_first {
    text-align: center; 
    width: 310px;
	background-color: #fff;
	
}

.engineering_zong_content_first div img {
    width: 100%;
	height: 100%;
	
    transition: transform 0.3s ease;
}

.engineering_zong_content_first h4,
.engineering_zong_content_first p {
    text-align: left; 
    margin-left: auto;
    margin-right: auto;
    width: 90%;
}

.engineering_zong_content_first h4{
	font-weight: bold;
}

.engineering_zong_content_first p {
    font-size: 12px;
	color: gray;
}

.engineering__bottom{
	text-align: center;
	margin-top: 30px;
}

.levitation {
    width: 50px;
    position: fixed; 
    top: 80%; 
    right: 20px; 
    transform: translateY(-50%); 
    z-index: 1000; 
}

.levitation div {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 50px;
	background-color: #053c96;
	border-radius: 50%;
	color: #fff;
}

#back-to-top {
    cursor: pointer;
    height: 55px;
}