/*圆形返回顶部CSS*/
#back_top a { /* back to top button */
    text-align: center;
    line-height: 50px;
    font-size: 16px;
    width:50px;
    height: 50px;
    position: fixed;
    bottom: 10px; /* 小按钮到浏览器底边的距离 */
    right: 60px; /* 小按钮到浏览器右边框的距离 */
    color: rgb(64,120,192); /* 小按钮中文字的颜色 */
    z-index: 1000;
    background: #fff; /* 小按钮底色 */
    padding: auto; /* 小按钮中文字到按钮边缘的距离 */
    border-radius: 50px; /* 小按钮圆角的弯曲程度（半径）*/
    -moz-border-radius: 50px;
    -webkit-border-radius: 50px;
    font-weight: bold; /* 小按钮中文字的粗细 */
    text-decoration: none !important;
    box-shadow:0 1px 2px rgba(0,0,0,.15), 0 1px 0 #ffffff inset;
}

#back_top a:hover { /* 小按钮上有鼠标悬停时 */
    background: rgba(64,120,192,0.8); /* 小按钮的底色 */
    color: #fff; /* 文字颜色 */
}

/*钢铁侠返回顶部CSS*/
#rocket {
    position: fixed;
    right: 50px;
    bottom: 50px;
    display: block;
    visibility: hidden;
    width: 42px;
    height: 43px;
    background: url("/assets/img/ironman.png") no-repeat 50% 0;
    opacity: 0;
    -webkit-transition: visibility 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335), opacity 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335), -webkit-transform 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335);
    -moz-transition: visibility 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335), opacity 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335), -moz-transform 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335);
    transition: visibility 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335), opacity 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335), transform 0.6s cubic-bezier(0.6, 0.04, 0.98, 0.335);
}
@media mq-mobile {
    #rocket {
        right: 12px;
        bottom: 20px;
    }
}
#rocket i {
    display: block;
    margin-top: 48px;
    height: 14px;
    background: url("/assets/img/ironman.png") no-repeat 50% -20px;
    opacity: 0.5;
    -webkit-transition: -webkit-transform 0.2s;
    -moz-transition: -moz-transform 0.2s;
    transition: transform 0.2s;
    -webkit-transform-origin: 50% 0;
    -moz-transform-origin: 50% 0;
    transform-origin: 50% 0;
}
#rocket:hover {
    background-position: 50% -44px;
}
#rocket:hover i {
    background-position: 50% 100%;
    -webkit-animation: flaming 0.7s infinite;
    -moz-animation: flaming 0.7s infinite;
    animation: flaming 0.7s infinite;
}
#rocket.show {
    visibility: visible;
    opacity: 1;
}
#rocket.launch {
    background-position: 50% -44px;
    opacity: 0;
    -webkit-transform: translateY(-500px);
    -moz-transform: translateY(-500px);
    -ms-transform: translateY(-500px);
    transform: translateY(-500px);
    pointer-events: none;
}
#rocket.launch i {
    background-position: 50% 100%;
    -webkit-transform: scale(1.4, 3.2);
    -moz-transform: scale(1.4, 3.2);
    transform: scale(1.4, 3.2);
}