h3.title {
    position: absolute;
    display: flex;
    justify-content: center;
    left: 0;
    right: 0;
    top: 450px;
    margin: auto;
    bottom: 0;
    color:#003399;
    font-size: 40px;
    font-weight: 500;
}

.content {
    perspective: 300px;
    width: 100%;
    position: relative;
}

.introduce{
        border-width:medium;
        border-style: solid;
        border-color:#003399;
        width: 900px;
        padding-left: 50px;
        padding-right:50px;
        padding-top:20px;
        padding-bottom:20px;
        margin-left: 200px;
        margin-top: 20px;
        text-align: center; 
        font-size: 20px;
        color: black;
}

.hobby{
    border-width:medium;
    border-style: solid;
    border-color:#003399;
    width: 900px;
    padding-left: 50px;
    padding-right:50px;
    padding-top:20px;
    padding-bottom:20px;
    margin-top: 20px;
    margin-left: 200px;
    text-align: center; 
    font-size: 20px;
    color: black;
}


.school{
    border-width:medium;
    border-style: solid;
    border-color:#003399;
    width: 900px;
    padding-left: 50px;
    padding-right:50px;
    padding-top:20px;
    padding-bottom:20px;
    margin-top: 20px;
    margin-left: 200px;
    text-align: center; 
    font-size: 20px;
    color: black;
}

.back_top{
    font-size:20px;
    text-align:cneter;
}