*{
    padding: 0%;
    margin: 0;
}
header{
    background-color: rgba(0, 0, 0, 0.855);
    height: 70px;
    width: 100%;
    position: fixed;
}
h1{
    color: rgb(255, 255, 255);
    position:absolute;
    top: 0;
    left: 1vw;
    line-height: 80px;
    background-image: url(images/4.ico);
    background-repeat: no-repeat;
    background-position: left;
    width: 90px;
    text-indent: 80%;
}
header a{
    color: aliceblue;
    text-decoration: none;
}
header a:hover{
    text-decoration: underline;
}
header li{
    display: inline;
    margin-right: 4vw;
}
header ul{
    position:absolute;
    right: 5vw;
    top: 0;
    line-height: 80px;
}
.checkbtn{
    font-size: 30px;
    color: antiquewhite;
    float: left;
    cursor: pointer;
    display: none;
}
#check{
    display: none;
}
.text{
    background-color: rgb(48, 190, 206);
    color: rgb(64, 182, 219);
    height: 80vh;
    background-image: url(images/2.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    display: flex;
    flex-direction: column;
    align-items: center;
    /* 水平对齐· */
}
.text h2{
    font-size: 60px;
    margin-top: 8%;
}
.text a{
    color: aliceblue;
    text-decoration: none;
    border: 1px solid #ACACAC;
    padding: 5px 10px;
    border-radius: 5px;
}
.text a:hover{
    text-decoration: underline;
}
.text h3{
    margin: 18px;
}
.a{
    background-color: rgba(0, 0, 0, 0.567);
    color: aliceblue;
    height: 250px;
    display: flex;
    flex-direction: column;
    align-items: center;
    /* 水平对齐· */
    justify-content: center;
    /* 垂直对齐 */
    font-size: 30px;
}
footer{
    background-color: black;
    height: 50px;
    color: aliceblue;
    display: flex;
    flex-direction: column;
    align-items: center;
    /* 水平对齐· */
    justify-content: center;
    /* 垂直对齐 */
    font-size: 10px;
}
.menu {
    display: none;
}
@media screen and (max-width: 768px) {
    header ul{
        display: none;
    }
    header h1{
        left: 50%;
        transform: translateX(-50%);
    }

    .menu {
        display: block;
        background-color: transparent;
        color: white;
        font-size: 35px;
        position: absolute;
        top: 15px;
        left: 15px;
        border: none;
        cursor: pointer;
    }
    .text{
        justify-content: center;
    }
}