h1 {
    background: #d2eef4;
    padding: 5px;
    border-radius: 6px;
}

h2 {
    text-align: center;
    background: #ddddff;
    padding: 5px;
    border-radius: 5px;
}

h3 {
    background: #4efbe3;
    padding: 5px;
    width: 70%;
    border-radius: 5px;
}

h4 {
    background: #009ACD;
    width: 50%;
    padding: 5px;
    border-radius: 5px;
}

h5 {
    color: #fff;
    font-family: "Microsoft YaHei", 微软雅黑, "MicrosoftJhengHei", 华文细黑, STHeiti, MingLiu;
    background-color: #44D08E;
    -moz-border-radius: 3px;
    border-radius: 3px;
    width: 35%;
    padding: 3px;
    margin: 10px 0px;
    text-shadow: 2px 2px 3px #404040;
}

#back-to-top {
    background-color: #3475E5;
    bottom: 0;
    box-shadow: 0 0 6px #3475E5;
    color: #444444;
    padding: 20px 20px;
    position: fixed;
    right: 100px;
    bottom: 30px;
    cursor: pointer;
}

#back-to-top a {
    font-size: 20px;
    color: #fff;
}