body, html, div, header, footer, nav, li, h1, h2, h3, h4, h5, h6 {
    padding: 0;
    margin: 0;
    box-sizing: border-box
}

.stat a:link {
    color: #bbb;
}

.stat a:visited {
    color: #bbb;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 400
}

html {
    height: 100%
}

body {
    font-family: 'Helvetica Neue', Helvetica, Arial, 'Microsoft YaHei', sans-serif;
    color: #333;
    background-image: url(https://ooo.0o0.ooo/2016/06/20/5768c606cf9cb.jpg);
    position: relative;
    min-height: 100%;
    padding-bottom: 190px
}

a {
    text-decoration: none
}

button {
    border: none;
    outline: none
}

hr {
    border: 0;
    border-top: 1px solid #eee;
    margin: 20px 0
}

h1 {
    font-size: 30px
}

h2 {
    font-size: 26px;
    border-bottom: 1px solid #eee;
    margin: 50px 0 25px
}

h3 {
    font-size: 23px;
    margin: 50px 0 20px
}

h4 {
    font-size: 19px;
    margin: 30px 0 10px
}

h5 {
    font-size: 17px;
    margin: 20px 0 10px
}

h6 {
    font-size: 16px;
    margin: 10px 0 5px
}

blockquote {
    color: #444;
    border-left: 5px solid #D6DBDF;
    padding-left: 15px;
    background: rgba(112, 138, 153, 0.1);
    padding: 10px 20px;
    margin: 0 0 20px
}

blockquote p:last-of-type {
    margin: 0
}

table {
    border-top: 2px solid #777;
    border-bottom: 2px solid #777;
    margin: 8px 0;
    border-collapse: collapse
}

table thead {
    border-bottom: 1px solid #777;
    background-color: #aaa;
    color: #fff
}

table th {
    padding: 2px 10px;
    text-align: left
}

table tbody tr:nth-of-type(2n+1) {
    background-color: #f8f8fd
}

table tbody tr:nth-of-type(2n) {
    background-color: #e5eaed
}

table td {
    padding: 2px 10px
}

p {
    margin: 0 0 10px
}

img {
    max-width: 100%
}

header {
    background: #222;
    height: 52px;
    color: #9d9d9d;
    box-shadow: 0 2px 4px 1px rgba(0, 0, 0, 0.5);
    margin-bottom: 20px
}

header a {
    color: #9d9d9d;
    -webkit-transition: 0.2s ease;
    transition: 0.2s ease
}

header a:hover {
    color: #fff
}

header .wrapper {
    width: 1140px;
    margin: 0 auto;
    line-height: 52px
}

header .wrapper .brand {
    font-size: 18px
}

header .wrapper small {
    margin-left: 26px;
    font-size: 14px
}

header .wrapper .menu {
    display: none
}

header .wrapper nav {
    float: right
}

header .wrapper nav ul {
    font-size: 0;
    margin: 0;
    padding: 0
}

header .wrapper nav ul li {
    list-style: none;
    font-size: 14px;
    display: inline-block;
    -webkit-transition: 0.2s ease;
    transition: 0.2s ease
}

header .wrapper nav ul li a {
    display: inline-block;
    padding: 0 10px;
    height: 52px
}

header .wrapper nav ul li a:hover {
    background-color: #000
}

header .wrapper nav ul li a i {
    margin-right: 5px
}

header .wrapper nav ul li > .active {
    color: #fff;
    background-color: #000;
    box-shadow: 0 25px 25px -15px rgba(255, 255, 255, 0.93)
}

@media screen and (max-width: 1200px) and (min-width: 770px) {
    header {
        height: 50px
    }

    header .wrapper {
        width: 90%;
        line-height: 50px
    }

    header .wrapper .brand {
        font-size: 16px
    }

    header .wrapper small {
        margin-left: 15px;
        font-size: 12px
    }

    header .wrapper .menu {
        display: none
    }

    header .wrapper nav ul li a {
        padding: 0 8px;
        height: 50px
    }

    header .wrapper nav ul li a i {
        margin-right: 4px
    }
}

@media screen and (max-width: 770px) {
    header {
        height: 48px;
        margin-bottom: 15px
    }

    header .wrapper {
        width: 95%;
        margin: 0 auto;
        line-height: 48px;
        position: relative;
        z-index: 101
    }

    header .wrapper .brand {
        font-size: 16px
    }

    header .wrapper small {
        margin-left: 10px;
        font-size: 12px
    }

    header .wrapper .menu {
        display: inline-block;
        position: absolute;
        z-index: -102;
        right: 0;
        top: 10px;
        padding: 5px 10px;
        background: #333;
        border: 1px solid #333;
        border-radius: 4px;
        color: #c9c9c9;
        font-size: 17px;
        -webkit-transition: 0.4s ease;
        transition: 0.4s ease
    }

    header .wrapper > .active {
        background: #000;
        color: #fff
    }

    header .wrapper .nav-show {
        visibility: visible;
        transform: scale(1);
        opacity: 1
    }

    header .wrapper nav {
        position: absolute;
        z-index: 100;
        right: 0;
        top: 47px;
        text-align: center;
        visibility: hidden;
        transform-origin: 100% 0%;
        transform: scale(0.1);
        opacity: 0;
        transition: 0.2s cubic-bezier(0.5, 0.1, 0.51, 1.38)
    }

    header .wrapper nav ul {
        background: #222;
        border-radius: 0 0 4px 4px;
        box-shadow: 0px 3px 4px 1px rgba(0, 0, 0, 0.5)
    }

    header .wrapper nav ul li {
        font-size: 14px;
        display: block;
        border-bottom: 1px solid #333
    }

    header .wrapper nav ul li a {
        display: block;
        padding: 0 10px;
        height: 40px;
        line-height: 40px
    }

    header .wrapper nav ul li:last-of-type {
        border: none
    }

    header .wrapper nav ul li > .active {
        color: #fff;
        background-color: #000;
        box-shadow: none
    }
}

#markdown-toc {
    display: none
}

.page[post] .label {
    margin-top: 16px;
    overflow: hidden
}

.page[post] .label .label-card {
    float: left;
    margin-right: 15px
}

.page[post] .label .label-card .point {
    padding: 0 10px;
    color: #9d9d9d
}

.page[post] .label .label-card i {
    padding-right: 5px;
    color: #6b6a6a
}

.page[post] a {
    color: #4d6dad;
    transition: 0.5s ease
}

.page[post] a:hover {
    color: #223253;
    background-color: #f4efeb
}

.page[post] .left ul > h2 {
    color: #333
}

.page[post] .left ul li {
    color: #333;
    margin: 0
}

@media screen and (max-width: 770px) {
    .page[post] .left {
        font-size: 15px
    }

    .page[post] .left h2 {
        font-size: 24px
    }

    .page[post] .left h3 {
        font-size: 20px
    }

    .page[post] .left h4 {
        font-size: 18px
    }

    .page[post] .left h5 {
        font-size: 16px
    }

    .page[post] .left h6 {
        font-size: 15px
    }
}

.clearfix:after {
    content: "\200B";
    display: block;
    height: 0;
    clear: both
}

.clearfix {
    *zoom: 1
}

.page {
    width: 1140px;
    box-sizing: border-box;
    margin: 0 auto
}

.page .left {
    width: 70%;
    float: left;
    padding: 20px 30px;
    line-height: 1.6;
    font-size: 16px;
    background-color: #f8f8fd;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 0 30px rgba(10, 10, 0, 0.1) inset
}

.page .left > h1 {
    margin-bottom: -10px
}

.page .left a:not([title]) {
    word-break: break-all
}

.page .left ul > h2 {
    margin-left: -40px;
    color: #6a6b6b
}

.page .left ul li {
    line-height: 1.8;
    color: #888888
}

.page .left ul li time {
    display: inline-block;
    width: 85px
}

.page .left ul li .title {
    font-weight: bold;
    color: #223253;
    transition: 0.3s ease
}

.page .left ul li .title:hover {
    color: #4d6dad
}

.page .left ul li i {
    margin-right: 5px
}

.page .left ul li .categories {
    padding: 0 15px
}

.page .left ul li .categories i {
    color: #9e9d9d
}

.page .left ul li .categories a {
    padding: 0 5px;
    background-color: #9e9d9d;
    color: #fff;
    font-size: 90%;
    transition: 0.3s ease
}

.page .left ul li .categories a:hover {
    background-color: #b6b6b9
}

.page .left ul li .pageTag i {
    color: #c6cbe9
}

.page .left ul li .pageTag a {
    padding: 0 5px;
    background-color: #c6cbe9;
    border-radius: 4px;
    color: #fff;
    font-size: 90%;
    transition: 0.3s ease
}

.page .left ul li .pageTag a:hover {
    background-color: #c0ddc7
}

.page .anchor {
    display: none
}

.page .right {
    float: left;
    width: 30%;
    padding-left: 20px;
    top: 0
}

.page .right .fixed {
    position: fixed;
    top: 20px
}

.page .right .scroll-bottom {
    position: absolute;
    bottom: 190px
}

.page .right .side {
    box-sizing: border-box;
    background-color: #f8f8fd;
    box-shadow: 0 1px 3px 1px rgba(0, 0, 0, 0.3), 0 0 30px rgba(10, 10, 0, 0.1) inset;
    padding-bottom: 0px;
    -ms-word-break: break-all;
    word-break: break-all;
    -webkit-hyphens: auto;
    -moz-hyphens: auto;
    -ms-hyphens: auto;
    hyphens: auto;
    margin-bottom: 20px;
}

.page .right .side > div {
    padding: 12px 15px;
    border-bottom: 1px solid #c0c0c0;
    font-size: 16px;
    font-weight: bold
}

.page .right .side a {
    color: #4d6dad;
    transition: 0.5s ease
}

.page .right .side a:hover {
    color: #223253
}

.page .right .content-ul {
    overflow-y: auto;
    padding-right: 10px;
    line-height: 1.8;
    padding-left: 35px
}

.page .right .content-ul ul {
    padding-left: 20px
}

@media screen and (max-width: 1200px) and (min-width: 770px) {
    .page {
        width: 90%
    }
}

@media screen and (max-width: 770px) {
    .page {
        width: 95%
    }

    .page .left {
        width: 100%;
        float: left;
        padding: 10px 14px;
        font-size: 14px
    }

    .page .left > h1 {
        font-size: 25px;
        margin-bottom: -10px
    }

    .page .left ul {
        padding-left: 20px
    }

    .page .left ul > h2 {
        font-size: 20px;
        margin-left: -20px
    }

    .page .left ul li {
        margin: 20px 0
    }

    .page .left ul li time {
        display: block;
        width: auto
    }

    .page .left ul li .title {
        display: block;
        font-size: 16px
    }

    .page .left ul li .categories {
        font-size: 12px;
        padding-left: 0;
        padding-right: 10px
    }

    .page .anchor {
        display: block;
        visibility: visible;
        position: fixed;
        top: 76px;
        right: 2.5%;
        padding: 5px 10px;
        color: #333;
        font-size: 15px;
        background-color: #f8f8fd;
        box-shadow: 0 0 8px 0 rgba(0, 0, 0, 0.3), 0 0 30px rgba(10, 10, 0, 0.1) inset;
        opacity: 0.7;
        transition: 0.2s cubic-bezier(0.5, 0.1, 0.51, 1.38)
    }

    .page .anchor-hide {
        opacity: 0;
        visibility: hidden
    }

    .page .right {
        visibility: hidden;
        position: fixed;
        float: none;
        width: auto;
        max-width: 95%;
        padding: 0;
        top: 76px;
        right: 2.5%;
        opacity: 0;
        transform-origin: 100% 0;
        transform: scale(0.1);
        transition: 0.2s cubic-bezier(0.5, 0.1, 0.51, 1.38)
    }

    .page .right-show {
        z-index: 999;
        visibility: visible;
        opacity: 1;
        transform: scale(1)
    }

    .page .right-show .content-ul {
        margin-bottom: 0
    }

    .page .right-show .content-ul > li:last-of-type {
        margin-bottom: 16px
    }
}

code {
    padding: 1px 4px;
    margin: 0 2px;
    font-size: 90%;
    border-radius: 3px;
    color: #000;
    background-color: rgba(0, 0, 0, 0.06);
    border: 1px solid #d7d0d2;
    font-family: Monaco, Menlo, "Microsoft YaHei Mono", Consolas, "Courier New", monospace, sans-serif
}

pre {
    margin: 12px 0;
    padding: 8px 12px;
    word-wrap: break-word;
    white-space: -moz-pre-wrap;
    white-space: pre-wrap
}

pre > code {
    margin: 0;
    padding: 0;
    font-size: 13px;
    color: #d1d1c9;
    border: none;
    background-color: #272822
}

.highlight {
    border-radius: 3px;
    background: #272822
}

.highlight .hll {
    background-color: #272822
}

.highlight .c {
    color: #75715e
}

.highlight .err {
    color: #960050;
    background-color: #1e0010
}

.highlight .k {
    color: #66d9ef
}

.highlight .l {
    color: #ae81ff
}

.highlight .n {
    color: #f8f8f2
}

.highlight .o {
    color: #f92672
}

.highlight .p {
    color: #f8f8f2
}

.highlight .cm {
    color: #75715e
}

.highlight .cp {
    color: #75715e
}

.highlight .c1 {
    color: #75715e
}

.highlight .cs {
    color: #75715e
}

.highlight .ge {
    font-style: italic
}

.highlight .gs {
    font-weight: bold
}

.highlight .kc {
    color: #66d9ef
}

.highlight .kd {
    color: #66d9ef
}

.highlight .kn {
    color: #f92672
}

.highlight .kp {
    color: #66d9ef
}

.highlight .kr {
    color: #66d9ef
}

.highlight .kt {
    color: #66d9ef
}

.highlight .ld {
    color: #e6db74
}

.highlight .m {
    color: #ae81ff
}

.highlight .s {
    color: #e6db74
}

.highlight .na {
    color: #a6e22e
}

.highlight .nb {
    color: #f8f8f2
}

.highlight .nc {
    color: #a6e22e
}

.highlight .no {
    color: #66d9ef
}

.highlight .nd {
    color: #a6e22e
}

.highlight .ni {
    color: #f8f8f2
}

.highlight .ne {
    color: #a6e22e
}

.highlight .nf {
    color: #a6e22e
}

.highlight .nl {
    color: #f8f8f2
}

.highlight .nn {
    color: #f8f8f2
}

.highlight .nx {
    color: #a6e22e
}

.highlight .py {
    color: #f8f8f2
}

.highlight .nt {
    color: #f92672
}

.highlight .nv {
    color: #f8f8f2
}

.highlight .ow {
    color: #f92672
}

.highlight .w {
    color: #f8f8f2
}

.highlight .mf {
    color: #ae81ff
}

.highlight .mh {
    color: #ae81ff
}

.highlight .mi {
    color: #ae81ff
}

.highlight .mo {
    color: #ae81ff
}

.highlight .sb {
    color: #e6db74
}

.highlight .sc {
    color: #e6db74
}

.highlight .sd {
    color: #e6db74
}

.highlight .s2 {
    color: #e6db74
}

.highlight .se {
    color: #ae81ff
}

.highlight .sh {
    color: #e6db74
}

.highlight .si {
    color: #e6db74
}

.highlight .sx {
    color: #e6db74
}

.highlight .sr {
    color: #e6db74
}

.highlight .s1 {
    color: #e6db74
}

.highlight .ss {
    color: #e6db74
}

.highlight .bp {
    color: #f8f8f2
}

.highlight .vc {
    color: #f8f8f2
}

.highlight .vg {
    color: #f8f8f2
}

.highlight .vi {
    color: #f8f8f2
}

.highlight .il {
    color: #ae81ff
}

.highlight .gu {
    color: #75715e
}

.highlight .gd {
    color: #f92672
}

.highlight .gi {
    color: #a6e22e
}

.page[index] a {
    color: #4d6dad;
    transition: 0.5s ease
}

.page[index] a:hover {
    color: #223253
}

.page[index] .left > ul {
    padding: 0
}

.page[index] .left > ul > li {
    list-style: none
}

.page[index] .left > ul li {
    color: #333
}

.page[index] .left > ul li h2 {
    border: none;
    font-size: 27px;
    margin: 0
}

.page[index] .left > ul li .label {
    margin-bottom: 15px;
    overflow: hidden
}

.page[index] .left > ul li .label .label-card {
    float: left;
    margin-right: 15px
}

.page[index] .left > ul li .label .label-card i {
    padding-right: 0;
    margin-right: 3px;
    color: #6b6a6a
}

.page[index] .left > ul li .label .categories {
    padding: 0
}

.page[index] .left > ul li .excerpt h2 {
    font-size: 24px
}

.page[index] .left > ul li .excerpt h3 {
    font-size: 22px
}

.page[index] .left > ul li .excerpt h4 {
    font-size: 20px
}

.page[index] .left > ul li .read-all {
    text-align: right;
    font-size: 14px
}

.page[index] .left > ul li .read-all a {
    color: #778ab0;
    transition: 0.2s ease
}

.page[index] .left > ul li .read-all a:hover {
    color: #5872a7
}

.page[index] .left > ul li .read-all a i {
    padding-right: 3px
}

.page[index] .left .pagination {
    text-align: center
}

.page[index] .left .pagination .previous, .page[index] .left .pagination .next {
    font-size: 20px;
    padding: 0 5px
}

.page[index] .left .pagination .page_number {
    padding: 0 5px
}

.page[index] .left .pagination .disable {
    color: #cbcbcb
}

.page[index] .right .wrap .side {
    margin-bottom: 20px;
    padding-bottom: 0
}

.page[index] .right .wrap .side i {
    margin-right: 3px
}

.page[index] .right .wrap .side .content-ul[cate] {
    overflow: hidden;
    list-style: none;
    margin: 0;
    padding: 0
}

.page[index] .right .wrap .side .content-ul[cate] li {
    font-size: 14px
}

.page[index] .right .wrap .side .content-ul[cate] li a {
    display: block;
    width: 100%;
    padding: 2px 0;
    border-bottom: 1px solid #eee
}

.page[index] .right .wrap .side .content-ul[cate] li a:hover {
    background-color: #dbdfee
}

.page[index] .right .wrap .side .content-ul[cate] li a:hover .badge {
    background-color: #dbdfee;
    transform: scale(1.2) rotate(360deg)
}

.page[index] .right .wrap .side .content-ul[cate] li a .name {
    padding-left: 15px
}

.page[index] .right .wrap .side .content-ul[cate] li a .badge {
    display: block;
    float: right;
    text-align: center;
    margin-right: 15px;
    margin-top: 3px;
    padding: 0 10px;
    font-size: 12px;
    color: #fff;
    background-color: #bbb;
    border-radius: 50%;
    transition: 0.5s ease-in-out
}

.page[index] .right .wrap .side .content-ul[cate] li:last-of-type a {
    border: none
}

.page[index] .right .wrap .side .content-ul[recent] {
    padding-bottom: 16px
}

.page[index] .right .wrap .side .content-ul[recent] li {
    color: #aaa;
    font-size: 14px
}

.page[index] .right .wrap .side .tags-cloud {
    font-weight: normal
}

.page[index] .right .wrap .side .tags-cloud a {
    padding: 0 3px;
    border-radius: 5px
}

.page[index] .right .wrap .side .tags-cloud a:hover {
    background-color: #f0e7ce
}

@media screen and (max-width: 770px) {
    .page[index] .left > ul li h2 {
        font-size: 22px
    }

    .page[index] .left > ul li .excerpt h2 {
        font-size: 20px
    }

    .page[index] .left > ul li .excerpt h3 {
        font-size: 18px
    }

    .page[index] .left > ul li .excerpt h4 {
        font-size: 16px
    }

    .page[index] .left > ul li .excerpt li {
        margin: 0
    }
}

.page[demo] .left {
    width: 100%
}

.page[demo] .left a {
    color: #4d6dad;
    transition: 0.5s ease
}

.page[demo] .left a:hover {
    color: #223253;
    background-color: #f4efeb
}

.page[demo] .left .grid {
    margin: 0 auto
}

.page[demo] .left .grid:after {
    content: '';
    display: block;
    clear: both
}

.page[demo] .left .grid .grid-item {
    width: 250px;
    background-color: #fff;
    margin-bottom: 20px;
    padding-bottom: 10px;
    float: left;
    transition: 0.5s ease;
    -webkit-transition: 0.5s ease;
    -moz-transition: 0.5s ease;
    -o-transition: 0.5s ease;
    -webkit-box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.3);
    -moz-box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.3);
    box-shadow: 0 0 10px 0 rgba(0, 0, 0, 0.3)
}

.page[demo] .left .grid .grid-item:hover {
    -webkit-box-shadow: 0 2px 30px -1px rgba(0, 0, 0, 0.6), inset 0 0 87px 0 rgba(184, 184, 184, 0.13);
    -moz-box-shadow: 0 2px 30px -1px rgba(0, 0, 0, 0.6), inset 0 0 87px 0 rgba(184, 184, 184, 0.13);
    box-shadow: 0 2px 30px -1px rgba(0, 0, 0, 0.6), inset 0 0 87px 0 rgba(184, 184, 184, 0.13)
}

.page[demo] .left .grid .grid-item .a-img {
    color: #fff
}

.page[demo] .left .grid .grid-item .a-img:hover {
    color: #fff;
    background-color: #fff
}

.page[demo] .left .grid .grid-item .demo-title {
    font-size: 18px;
    font-weight: bold;
    margin: 0 8px
}

.page[demo] .left .grid .grid-item p {
    margin: 0;
    padding: 0 8px;
    font-size: 14px
}

.deep {
    transition: 0.32s cubic-bezier(0.46, 0.03, 0.52, 0.96);
    transform-style: preserve-3d;
    transform: perspective(1600px) rotateX(14deg) translateZ(-200px)
}

.site-footer {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    text-align: center;
    background-color: #2b2b3c;
    box-shadow: 0 -2px 4px 1px rgba(0, 0, 0, 0.5);
    color: #bbb
}

.site-footer .wrapper {
    width: 1140px;
    margin: 0 auto;
    padding: 15px 0;
    text-align: center;
    font-size: 14px
}

.site-footer .wrapper p {
    margin: 0;
    line-height: 1.6
}

.site-footer .wrapper .contact {
    display: inline-block
}

.site-footer .wrapper .contact a {
    color: #ccc;
    transition: 0.3s ease
}

.site-footer .wrapper .contact a:hover {
    color: #fff
}

.site-footer .wrapper .contact a i {
    margin: 0 5px;
    font-size: 20px
}

.site-footer .wrapper .description {
    display: inline-block
}

.site-footer .wrapper .power a {
    color: #8F90C5;
    transition: 0.3s ease
}

.site-footer .wrapper .power a:hover {
    color: #fff
}

@media screen and (max-width: 1200px) and (min-width: 770px) {
    .site-footer .wrapper {
        width: 90%
    }
}

@media screen and (max-width: 770px) {
    .site-footer .wrapper {
        width: 90%
    }
}

.content-ul::-webkit-scrollbar {
    width: 7px;
    height: 6px
}

.content-ul::-webkit-scrollbar-button {
    width: 0;
    height: 0
}

.content-ul::-webkit-scrollbar-thumb {
    background: #D3D3D3;
    border: 0 none #ffffff;
    border-radius: 50px
}

.content-ul::-webkit-scrollbar-thumb:hover {
    background: #a8a8a8
}

.content-ul::-webkit-scrollbar-thumb:active {
    background: #787878
}

.content-ul::-webkit-scrollbar-track {
    background: #F1F1F1;
    border-radius: 50px
}

.content-ul::-webkit-scrollbar-track:hover {
    background: #e2e2e2
}

.content-ul::-webkit-scrollbar-track:active {
    background: #cccccc
}

.content-ul::-webkit-scrollbar-corner {
    background: transparent
}

.back-to-top {
    position: fixed;
    left: 50%;
    margin-left: 580px;
    bottom: 37px;
    background-color: #f8f8fd;
    visibility: hidden;
    opacity: 0;
    transition: 0.4s ease;
    box-shadow: 0 1px 3px 1px rgba(0, 0, 0, 0.3), 0 0 30px rgba(10, 10, 0, 0.1) inset
}

.back-to-top a {
    display: block;
    background-color: #eee;
    width: 38px;
    height: 38px;
    line-height: 38px;
    text-align: center;
    font-size: 20px;
    color: #b4b4b4
}

.back-to-top-show {
    visibility: visible;
    opacity: 0.7
}

.back-to-top-show:hover {
    opacity: 1
}

@media screen and (max-width: 1200px) and (min-width: 770px) {
    .back-to-top {
        left: 50%;
        margin-left: 45.5%
    }
}

@media screen and (max-width: 770px) {
    .back-to-top {
        right: 2.5%;
        left: auto;
        margin-left: 0px
    }

    .back-to-top a {
        width: 33px;
        height: 33px;
        line-height: 33px;
        text-align: center;
        font-size: 18px
    }
}