*{
    margin: 0;
    padding: 0;
}
body,html{
    width: 100%;
    height: 100%;
    background: url("../img/bg.png") center no-repeat;
    background-size: cover;
    background-attachment: fixed;
    color: #ffffff;
}
.header{
    width: 100%;
    padding-top: 20px;
}
.header>p{
    font-size: 18px;
}
.header>p>a{
    text-decoration: none;
    color: #ffffff;
    padding: 0 20px;
}
.header>p>a:hover{
    color: cadetblue;
}
.top-header{
    width: 55%;
    list-style: none;
    overflow: hidden;
    margin: 0 auto;
    padding: 10px 0;
    font-size: 24px;
}
.top-header>li{
    float: left;
}
.top-header>li>a{
    padding: 0 20px;
    cursor: pointer;
    text-decoration: none;
    color: #ffffff;
}
p{
    text-align: center;
}
.top-header>li>a:hover{
    color: cadetblue;
}
.font-level-one{
    font-size: 16px;
}
.font-level-two{
    font-size: 18px;
}
.font-level-three{
    font-size: 28px;
}
.font-level-four{
    font-size: 40px;
}
ul,li{
    list-style: none;
}
a.video-url{color: #FFFFFF;text-decoration: none;}
/* a.video-url:link {color: blue} /* 未被访问的链接 蓝色 */ */
a.video-url:visited {color: blue} /* 已被访问过的链接 蓝色 */
a.video-url:hover {color: cadetblue;text-decoration: underline;} /* 鼠标悬浮在上的链接 蓝色 */
a.video-url:active {color: #FFFFFF} /* 鼠标点中激活链接 蓝色 */