/* 全局样式重置与基础设置 */
html {
  -ms-text-size-adjust: 100%;
  -webkit-text-size-adjust: 100%;
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  line-height: 1.5;
  font-size: 14px;
  font-family: 'PingFangSC-Regular', 'helvetica neue', tahoma, 'PingFang SC', 'microsoft yahei', arial, 'hiragino sans gb', sans-serif;
  -webkit-font-smoothing: antialiased;
  margin: 0;
  padding: 0;
}

/* 基础HTML元素重置 */
html,
body,
div,
span,
applet,
object,
iframe,
h1,
h2,
h3,
h4,
h5,
h6,
p,
blockquote,
pre,
a,
abbr,
acronym,
address,
big,
cite,
code,
del,
dfn,
em,
img,
ins,
kbd,
q,
s,
samp,
small,
strike,
strong,
sub,
sup,
tt,
var,
dl,
dt,
dd,
ol,
ul,
li,
fieldset,
form,
label,
legend,
table,
caption,
tbody,
tfoot,
thead,
tr,
th,
td {
  margin: 0;
  padding: 0;
}

/* 列表样式 */
ul,
ol,
li {
  list-style: none;
}

/* 标题样式 */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-size: 100%;
  font-variant: normal;
  font-weight: normal;
}

/* 表单元素样式 */
button,
input,
optgroup,
select,
textarea {
  color: inherit;
  font: inherit;
  margin: 0;
  padding: 0;
  border: 0;
  background: 0;
  outline: none;
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
}

textarea {
  resize: none;
}

/* 图片样式 */
img {
  border: 0;
  vertical-align: bottom;
  max-width: 100%;
  height: auto;
}

/* 链接样式 */
a {
  color: inherit;
  text-decoration: none;
  -webkit-tap-highlight-color: rgba(0, 0, 0, 0);
  outline: none;
  background: none;
}

a:hover,
a:active,
a:visited,
a:link,
a:focus {
  text-decoration: none;
}

/* 布局组件样式 */

/* 头部导航样式 */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background-color: rgba(0, 0, 0, 0.2);
  transform: translateY(0);
  transition: transform 0.3s ease, background-color 0.3s ease;
  will-change: transform;
}

/* 隐藏header的类，将通过JavaScript添加/移除 */
.header.hide {
  transform: translateY(-100%);
}

/* 蓝色背景的类，将在向上滚动时通过JavaScript添加 */
.header.blue-bg {
  background-color: #0055dd;
}

.nav-container {
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 66px;
}

/* 导航下方的渐变横线样式 */
.box {
    background: radial-gradient(#d8d8d881 20%, transparent 57%);
    height: 1px;
    margin: 0 auto;
    width: 100%;
}

/* 左边logo区域 */
.nav-left {
    flex: 0 0 auto;
}

.logo {
    display: flex;
    justify-content: center;
    width: 210px;
}

.logo img {
    width: 100%;
}

/* 中间菜单区域 */
.nav-center {
    flex: 1;
    display: flex;
    justify-content: center;
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

.nav-item {
    position: relative;
    margin: 0 28px;
}

/* 隐藏加入我们菜单项 */
.nav-item:nth-child(7) {
    display: none;
}

.nav-link {
    color: #fff;
    font-size: 16px;
    font-weight: 500;
    position: relative;
    transition: all 0.3s ease;
}

/* 添加链接下方的装饰线 */
.nav-link::after {
    content: '';
    position: absolute;
    top: 26px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 4px;
    background-color: #0055dd;
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* 右边语言选择区域 */
.nav-right {
    flex: 0 0 auto;
}

.language-selector {
    position: relative;
}

.language-btn {
    border: 1px solid rgba(255, 255, 255, 0.4);
    color: white;
    min-width: 100px;
    width: 100%;
    height: 32px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 5px;
    transition: all 0.3s ease;
    backdrop-filter: blur(5px);
}

.language-btn:hover {
    background-color: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.6);
}

/* 语言箭头样式 */
.language-arrow {
    width: 0;
    height: 0;
    border-left: 4px solid transparent;
    border-right: 4px solid transparent;
    border-top: 5px solid white;
    display: inline-block;
    margin-left: 5px;
    transition: transform 0.3s ease;
}

.language-selector:hover .language-arrow {
    transform: rotate(180deg);
}

/* 语言下拉菜单 */
.language-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: 5px;
    background-color: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 4px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    min-width: 100px;
    display: none;
    z-index: 1001;
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
}

.language-selector:hover .language-dropdown {
    display: block;
}

.language-option {
    display: block;
    padding: 10px 20px;
    color: white;
    text-decoration: none;
    font-size: 14px;
    transition: background-color 0.3s ease;
}

.language-option:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: #0055dd;
}
/** Header E **/

/** Footer S **/
.footer {
    width: 100%;
    background-color: #f1f3f4;
}

.footer-content {
    max-width: 1400px;
    margin: 0 auto;
}

/* 页脚顶部 */
.footer-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    height: 10.25rem;
}

.footer-logo {
    width: 210px;
}

.footer-logo img {
    width: 100%;
}

.footer-social {
    display: flex;
    align-items: center;
    gap: 15px;
}

.social-title {
    color: #5f6464;
    font-size: 1.375rem;
    height: 2.3125rem;
    line-height: 2.3125rem;
    width: 9.375rem;
}

.social-icons {
    display: flex;
    justify-content: space-between;
    width: 270px;
}

.social-icon {    
    width: 37px;    
    height: 37px;    
    background-color: transparent;    
    border: 1px solid #ccc;    
    border-radius: 8px;    
    background-size: 26px 26px;    
    background-repeat: no-repeat;    
    background-position: center;    
    position: relative;    
    display: inline-block;
}


/* 响应式菜单按钮样式 */
.mobile-menu-btn {
    display: none;
    cursor: pointer;
    margin-left: 20px;
}

/* 汉堡菜单图标 - 标准三条杠样式 */
.menu-icon {
    display: inline-block;
    width: 24px;
    height: 20px;
    position: relative;
    cursor: pointer;
}

/* 定义三条水平线样式 */
.menu-icon::before,
.menu-icon::after,
.menu-icon span {
    content: '';
    position: absolute;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: white;
    transition: all 0.3s ease;
    border-radius: 3px;
}

/* 顶部横线 */
.menu-icon::before {
    top: 0;
}

/* 底部横线 */
.menu-icon::after {
    bottom: 0;
}

/* 中间横线 */
.menu-icon span {
    top: 50%;
    transform: translateY(-50%);
}

/* 汉堡图标激活状态动画 */
.menu-icon.active::before {
    top: 50%;
    transform: translateY(-50%) rotate(45deg);
}

.menu-icon.active::after {
    bottom: 50%;
    transform: translateY(50%) rotate(-45deg);
}

.menu-icon.active span {
    opacity: 0;
}

/* 响应式设计 - 小屏幕显示汉堡菜单 */
@media (max-width: 768px) {
    /* 修改头部高度为56px */
    .nav-container {
        height: 56px;
    }
    
    .nav-center {
        position: absolute;
        top: 60px;
        left: 10px;
        min-width: 150px;
        background-color: #fff;
        border-radius: 8px;
        padding: 25px 20px;
        z-index: 99;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        /* 默认隐藏菜单 */
        opacity: 0;
        visibility: hidden;
        pointer-events: none;
        transition: all 0.3s ease;
    }
    
    /* 激活状态显示菜单 */
    .nav-center.active {
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
    }
    
    /* 菜单顶部向上的箭头 */
    .nav-center::before {
        content: '';
        position: absolute;
        top: -13px;
        left: 9px;
        width: 0;
        height: 0;
        border-left: 14px solid transparent;
        border-right: 14px solid transparent;
        border-bottom: 14px solid #fff;
    }
    
    .nav-center nav {
        width: 100%;
    }
    
    .nav-menu {
        flex-direction: column;
        gap: 25px;
    }
    
    .nav-item {
        margin: 0;
    }
    
    /* 响应式菜单中的字体颜色 - 独立设置，不影响非响应式状态 */
    .nav-center .nav-link {
        color: #333;
        font-size: 16px;
    }
    
    .mobile-menu-btn {
        display: block;
        margin-left: 0;
        order: 1;
    }
    
    .nav-container {
        justify-content: center;
        position: relative;
        width: 100%;
    }
    
    .nav-left {
        order: 2;
    }
    
    /* 将菜单按钮固定在左侧 */
    .nav-container .mobile-menu-btn {
        position: absolute;
        left: 20px;
        top: 50%;
        transform: translateY(-50%);
    }
    
    /* 响应式时隐藏语言选择器 */
    .language-selector {
        display: none;
    }
}

/* 微信二维码样式 */
.wechat-qrcode {
    width: 160px;
    height: 160px;
    position: absolute;
    top: -190px;
    left: 50%;
    transform: translateX(-50%);
    background: white;
    padding: 10px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
    text-align: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
    z-index: 1000;
}

.wechat-qrcode::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 5px solid white;
}

.wechat-qrcode img {
    display: block;
    margin-bottom: 5px;
    border-radius: 4px;
    object-fit: cover;
    box-sizing: border-box;
}

.wechat-qrcode span {
    font-size: 12px;
    color: #333;
}

/* 悬停显示二维码 */
.social-icon.wechat:hover .wechat-qrcode {
    opacity: 1;
    visibility: visible;
}

.social-icon.wechat {
    background-image: url('../img/icon_wechat.png');
}

.social-icon.weibo {
    background-image: url('../img/icon_weibo.png');
}

.social-icon.douyin {
    background-image: url('../img/icon_douyin.png');
}

.social-icon.bilibili {
    background-image: url('../img/icon_bilibili.png');
}

.social-icon.zhihu {
    background-image: url('../img/icon_zhihu.png');
}

.social-icon.kuaishou {
    background-image: url('../img/icon_kuaishou.png');
}

/* 社交媒体图标hover效果 */
.social-icon.wechat:hover {
    background-image: url('../img/icon_weichat_hover.png');
    border: 1px solid #22ac38;
}

.social-icon.weibo:hover {
    background-image: url('../img/icon_weibo_hover.png');
    border: 1px solid #d81e06;
}

.social-icon.douyin:hover {
    background-image: url('../img/icon_douyin_hover.png');
    border: 1px solid #000000;
}

.social-icon.bilibili:hover {
    background-image: url('../img/icon_bilibili_hover.png');
    border: 1px solid #0bb3ff;
}

.social-icon.zhihu:hover {
    background-image: url('../img/icon_zhihu_hover.png');
    border: 1px solid #0066ff;
}

.social-icon.kuaishou:hover {
    background-image: url('../img/icon_kuaishou_hover.png');
    border: 1px solid #ff6734;
}

/* 页脚链接部分 */
.footer-links {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    padding: 60px 0;
    border-top: 1px solid #dadce0;
    border-bottom: 1px solid #dadce0;
}

.footer-column-title {
    color: #5f6464;
    font-size: 1.25rem;
    margin-bottom: 30px;
}

.footer-nav {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-nav li {
    margin-bottom: 18px;
}

.footer-nav a {
    color: #5f6464;
    font-size: 1rem;
    transition: color 0.3s;
}

.footer-nav a:hover {
    color: #0055dd;
}

/* 页脚底部 */
.footer-bottom {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 7.25rem;
    width: 100%;
}

.footer-copyright,
.footer-rights {
    font-size: 16px;
    color: #5f6464;
    margin: 5px 0;
}

.footer-rights a {
    color: #5f6464;
    margin: 0 .2rem;
    transition: color 0.3s;
}

.footer-rights a:hover {
    color: #0055dd;
}

/** Footer E **/

/* 页脚响应式设计 - 768px断点 */
@media (max-width: 768px) {
    /* 隐藏页脚logo */
    .footer-logo {
        display: none;
    }
    
    /* 调整页脚顶部布局，让'关注我们'居左 */
    .footer-top {
        justify-content: flex-start;
        height: auto;
    }
    
    .footer-social {
        width: 100%;
        height: 8.125rem;
        padding: 0 20px;
        justify-content: flex-start;
    }
    
    .social-title {
        width: auto;
        margin-right: 15px;
        font-size: 1rem;
    }
    
    .social-icons {
        width: auto;
        gap: 10px;
    }
    
    .social-icon {
        width: 32px;
        height: 32px;
        background-size: 22px 22px;
    }
    
    /* 页脚链接部分响应式 - 菜单开合功能 */
    .footer-links {
        padding: 30px 20px;
        flex-direction: column;
    }
    
    .footer-column {
        width: 100%;
    }
    
    /* 标题样式 - 带箭头指示器 */
    .footer-column-title {
        position: relative;
        padding-right: 20px;
        font-size: 16px;
        line-height: 52px;
        cursor: pointer;
        margin-bottom: 0;
    }
    
    /* 箭头指示 */
    .footer-column-title::after {
        content: '';
        position: absolute;
        right: 0;
        top: 50%;
        width: 16px;
        height: 16px;
        background-image: url('../img/icon_arrow_d.png');
        background-size: contain;
        background-repeat: no-repeat;
        transform: translateY(-50%);
        transition: transform 0.3s;
    }
    
    /* 箭头旋转动画 - 展开状态 */
    .footer-column-title.expanded::after {
        transform: translateY(-50%) rotate(180deg);
    }
    
    /* 菜单默认关闭状态 */
    .footer-nav {
        overflow: hidden;
        max-height: 0;
        transition: max-height 0.3s ease;
    }
    
    /* 菜单项样式 */
    .footer-nav li {
        padding: 9px 0;
    }
    
    .footer-nav a {
        font-size: 14px;
    }
    
    /* 页脚底部响应式 */
    .footer-bottom {
        flex-direction: column;
        height: auto;
        text-align: center;
        padding: 20px 0;
    }
    
    .footer-copyright,
    .footer-rights {
        font-size: 14px;
    }
    
    .footer-rights {
        flex-direction: column;
        gap: 8px;
    }
}

/* =========================================================================== */
/* 通用组件样式 - 可在多个页面复用                                                  */
/* =========================================================================== */

/** 通用Banner样式 **/
.banner {
    position: relative;
    height: 611px;
    display: flex;
    color: white;
    overflow: hidden;
}

.banner-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: 0;
}

.banner-content {
    position: relative;
    text-align: left;
    z-index: 1;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    box-sizing: border-box;
}

.banner-title {
    font-size: 44px;
    font-weight: 700;
    margin: 0 0 10px 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
}

.banner-subtitle {
    font-size: 24px;
    margin: 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
}

/* Banner响应式样式 */

@media (max-width: 768px) {
    .banner {
        height: 300px;
    }
    .banner-title {
        font-size: 28px;
    }
    .banner-subtitle {
        font-size: 16px;
    }
}

/** 通用锚点样式 S **/

/* 锚点导航样式 S */
.anchor-nav {
    position: sticky;
    top: 0;
    background-color: #fff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    z-index: 900;
    width: 100%;
}

/* 锚点导航内容容器 */
.anchor-container {
    display: flex;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
    height: 70px;
}

/* 锚点项样式 */
.anchor-item {
    display: inline-block;
    color: #5F6464;
    font-size: 18px;
    line-height: 70px;
    position: relative;
    text-decoration: none;
    transition: color 0.3s ease;
    margin-right: 56px;
}

/* 锚点项悬停效果 */
.anchor-item:hover {
    color: #0055dd;
}

/* 锚点项激活状态样式 */
.anchor-item.active {
    color: #0055dd;
}

/* 激活状态下划线效果 */
.anchor-item.active::after {
    content: ' ';
    height: 2px;
    width: 100%;
    background: #0055dd;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0px;
}

/* 锚点导航样式 E */

/* 锚点导航响应式样式 */
@media (max-width: 768px) {
  
    .anchor-container {
        height: 50px;
        line-height: 50px;
        padding: 0 20px;
    }
    .anchor-item {
        font-size: 14px;
        margin-right: 26px;
    }
}

/* 内容区域基础样式 S */
/* 页面交差背景 */
.section-bg-1,
.section-bg-3,
.section-bg-5,
.section-bg-7,
.section-bg-9 {
    background-color: #ffffff;
}

.section-bg-2,
.section-bg-4,
.section-bg-6,
.section-bg-8 {
    background-color: #f8f9fa;
}

/* 内容版块上下间距 */
.doc-detail {
    padding-top: 66px;
   }
.section-content {
    padding: 40px 0;
    min-height: auto;
}

/* 版块标题样式组件 */
.content-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 40px 0;
    width: 100%;
    box-sizing: border-box;
}

/* 版块头部样式 */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* 版块标题样式 */
.section-title {
    font-size: 36px;
    color: #333;
    margin: 0;
    font-weight: 700;
    position: relative;
}

/* 标题下划线元素 */
.title-underline {
    height: .375rem;
    margin: 20px 0 60px;
    width: 33px;
    background-color: #0055dd;
}

/* 查看更多链接样式 */
.view-all {
    display: inline-flex;
    align-items: center;
    color: #5F6464;
    font-size: 22px;
    transition: color 0.3s ease;
}

.view-all:hover {
    color: #0055dd;
}

.view-all::after {
    content: '';
    display: inline-block;
    width: 20px;
    height: 14px;
    margin-left: 8px;
    vertical-align: middle;
    background-image: url('../img/more-awart.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}

.view-all:hover::after {
    background-image: url('../img/more-awart-hover.png');
}

/* 版块标题响应式样式 */
@media (max-width: 768px) {
    .section-content {
        padding: 25px 15px;
    }
    .content-container {
        padding: 0;
    }
    .section-title {
        font-size: 22px;
    }
    .title-underline {
        width: 25px;
        margin: 12px 0 30px;
    }
    .section-header {
        align-items: flex-start;
    }
    .view-all {
        font-size: 16px;
    }
}

.view-all:hover {
    color: #0055dd;
}

.view-all::after {
    content: '';
    display: inline-block;
    width: 20px;
    height: 18px;
    margin-left: 8px;
    vertical-align: middle;
    background-image: url('../img/more-awart.png');
    background-size: contain;
    background-repeat: no-repeat;
    background-position: center;
}

.view-all:hover::after {
    background-image: url('../img/more-awart-hover.png');
}
/** 通用内容区域样式 E **/

/** 内页Banner样式 **/
.nybanner {
    position: relative;
    height: 400px;
    display: flex;
    color: white;
    overflow: hidden;
}

.nybanner-image {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: 0;
}

.nybanner-content {
    position: relative;
    text-align: left;
    z-index: 1;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    box-sizing: border-box;
}

.nybanner-title {
    font-size: 40px;
    font-weight: 700;
    margin: 0 0 10px 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
}

.nybanner-subtitle {
    font-size: 24px;
    margin: 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.5);
}

/* Banner响应式样式 */

@media (max-width: 768px) {
    .nybanner {
        height: 300px;
    }
    .nybanner-title {
        font-size: 28px;
    }
    .nybanner-subtitle {
        font-size: 16px;
    }
}

/* 面包屑导航样式 S */
.breadcrumb-nav {
    background-color: #fff;
    height: 80px;
    display: flex;
    align-items: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.breadcrumb {
    display: flex;
    list-style: none;
    padding: 0;
    margin: 0;
    font-size: 20px;
    color: #666;
}

.breadcrumb a {
    text-decoration: none;
    transition: color 0.3s;
    margin-left: 16px;
    margin-right: 16px;
}

.breadcrumb a:nth-child(1) {
    margin-left: 0;
}

.breadcrumb a:hover {
    color: #0055dd;
}

.breadcrumb a:last-child {
    color: #0055dd;
    padding-right: 0;
    font-weight: 600;
}

/* 面包屑导航响应式样式 */
@media (max-width: 768px) {
    .breadcrumb-nav {
        height: 50px;
        padding: 0 20px;
    }
    .breadcrumb {
        font-size: 14px;
    }
    .breadcrumb li {
        padding-right: 20px;
    }
}
/* 面包屑导航样式 E */

/* 回到顶部按钮样式 - 使用伪元素创建箭头 */
.back-to-top {
    position: fixed;
    bottom: 40px;
    right: 40px;
    width: 50px;
    height: 50px;
    background-color: #ffffff;
    border-radius: 50%;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all 0.3s ease;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    border: 1px solid #0055dd;
    z-index: 999;
}

/* 使用伪元素创建向上的箭头 */
.back-to-top::before {
    content: "";
    display: block;
    width: 12px;
    height: 12px;
    position: absolute;
    top: calc(50% - 3px);
    left: calc(50% - 6px);
    transform: rotate(-135deg);
    border-bottom: 1px solid #0055dd;
    border-right: 1px solid #0055dd;
}
.back-to-top:hover{ background: #0055dd; }
.back-to-top:hover::before{
    border-bottom: 1px solid #FFF;
    border-right: 1px solid #FFF;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:active {
    transform: translateY(0);
}

/* 回到顶部按钮响应式样式 */
@media (max-width: 768px) {
    .back-to-top {
        bottom: 20px;
        right: 20px;
        width: 40px;
        height: 40px;
    }
    
    .back-to-top::before {
        border-left: 6px solid transparent;
        border-right: 6px solid transparent;
        border-bottom: 9px solid white;
    }
}