* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: Helvetica, "PingFang SC", "Microsoft Yahei", sans-serif;
  font-size: 14px;
}
a {
  text-decoration: none;
}
img {
  width: 100%;
}

:root {
  --primary-color: #2d6bff;
  --secondary-color: #e3e3e3;
  --text-color-lightest: #e7e9ec;
  --text-color-darker: #2e2e2e;
  --text-color-dark: #494949;
  --text-color-gray: #444444;
  --text-color-dark-gray: #727272;
  --text-color-light-gray: #c6c6c6;
  --mask-color: rgba(42, 42, 42, 0.69);
}

header {
  width: 100vw;
  height: 80px;
  display: grid;
  padding: 0 40px;
  grid-template-columns: 1fr 2fr;
  align-items: center;
  position: relative;
  z-index: 200;
}
header .logo {
  font-size: 24px;
  font-weight: 600;
  color: #fff;
}

header nav {
  justify-self: end;
}
header nav a {
  color: #fff;
  font-size: 16px;
  margin: 0 24px;
}

header nav a.active {
  color: var(--primary-color);
  position: relative;
}

header nav a.active::after {
  content: "";
  display: inline-block;
  width: 80%;
  height: 2px;
  border-radius: 1px;
  transform: translateY(8px);
  background-color: var(--primary-color);
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: auto;
}

header .burger {
  display: none;
}
.burger-line1 {
  transform-origin: center center;
}

/* 页面下滑时固定导航，背景设置为白色 */
header.sticky {
  position: fixed;
  background-color: white;
  box-shadow: 0 0 18px rgba(0, 0, 0, 0.2);
  animation: dropDown 0.5s ease-in-out forwards;
}

/* 固定导航文字颜色为黑色 */
header.sticky .logo,
header.sticky nav a,
header.sticky nav i {
  color: var(--text-color-darker);
}

@keyframes dropDown {
  from {
    transform: translateY(-80px);
  }
  to {
    transform: translateY(0);
  }
}

.banner {
  position: relative;
  top: -80px;
  z-index: 50;
}
.banner-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
}

.banner-wrap .banner-img {
  object-fit: cover;
  width: 100vw;
  height: 100vh;
}
.banner-content {
  position: absolute;
  z-index: 70;
  color: #fff;
  text-align: center;
  max-width: 60vw;
}

.banner-content h1 {
  font-size: 54px;
  font-weight: 600;
}

.banner-content h3 {
  font-size: 24px;
  margin: 48px 0;
}

.banner-content .contact-btn {
  padding: 12px 32px;
  background: linear-gradient(150deg, #3ea3f4 0%, #2d6bff 100%);
  border: 0;
  border-radius: 4px;
  color: #fff;
  font-size: 18px;
  cursor: pointer;
  outline: none;
}
.banner-content > * {
  opacity: 0;
}

.banner-mask {
  background: var(--mask-color);
  opacity: 0.5;
  position: absolute;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 60;
}

.content {
  display: flex;
  flex-direction: column;
  align-items: center;
}

section {
  display: grid;
  justify-items: center;
  max-width: 1200px;
  padding: 0 40px;
}
.about {
  margin-top: -24px;
  margin-bottom: 80px;
}
.about-wrap {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  column-gap: 5vw;
  align-items: center;
}
.about-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.about-item img {
  width: 42px;
  height: 42px;
  margin-bottom: 12px;
}

/* 标题 */
.about-item-title {
  font-size: 18px;
  color: var(--text-color-darker);
}

/* 内容 */
.about-item-desc {
  color: var(--text-color-gray);
  margin-top: 8px;
}
.category {
  margin-bottom: 80px;
}
.category-wrap {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  column-gap: 24px;
  row-gap: 24px;
}
.category-item {
  box-shadow: 0px 0px 2px rgba(0, 0, 0, 0.1);
  padding: 24px;
  transition: 0.4s;
  height: 500px;
  position: relative;
  overflow: hidden;
}

.category-item-wrap {
  height: 500px;
  overflow: hidden;
  margin: -24px;
  margin-bottom: 0;
  transition: 0.4s;
}
.category-item-wrap img {
  height: 500px;
  object-fit: cover;
}

.category-item-con {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  margin: auto;
  color: #fff;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding: 24px;
  background: rgba(0, 0, 0, 0.2);
}

.category-item:hover .category-item-con {
  background: transparent;
}
.category-item:hover .category-item-wrap {
  transform: scale(1.2);
}

.category-item-title {
  color: #fff;
  font-size: 18px;
  margin-bottom: 12px;
}
.category-item-desc {
  color: #fff;
  line-height: 24px;
  margin-bottom: 12px;
}
.category-btn-wrap {
  margin-top: 12px;
}
.category-item-btn button {
  border: 0;
  color: #fff;
  background: linear-gradient(150deg, #3ea3f4 0%, #2d6bff 100%);
  border-radius: 4px;
  padding: 6px 14px;
  position: relative;
  transition: 0.4s;
  display: block;
  cursor: pointer;
  outline: none;
}

.service {
  margin-bottom: 80px;
}
.service-wrap {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: 1fr 1fr;
  column-gap: 24px;
  row-gap: 24px;
}
.service-item {
  padding: 24px;
  border: 1px solid rgba(0, 0, 0, 0.06);
  transition: 0.4s;
  position: relative;
}
.service-item-wrap {
  position: relative;
}
.service-item .iconfont {
  font-size: 28px;
  color: #223463;
  padding: 10px 0;
}

.service-item-title {
  color: var(--text-color-darker);
  font-size: 20px;
  font-weight: 400;
}

.service-item-desc {
  color: var(--text-color-gray);
  line-height: 1.5;
  font-size: 14px;
  margin: 12px 0;
}

.service-desc {
  padding: 24px;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: none;
}
.service-desc-wrap {
  position: relative;
}
.service-desc-title {
  color: var(--text-color-darker);
  font-size: 34px;
  font-weight: 600;
  margin-bottom: 12px;
}
.service-desc-subtitle {
  color: var(--text-color-gray);
  line-height: 1.5;
  font-size: 14px;
}
.service-desc-btn {
  padding: 8px 10px;
  background: linear-gradient(150deg, #3ea3f4 0%, #1c53ff 100%);
  border: 0;
  border-radius: 4px;
  color: #fff;
  font-size: 14px;
  cursor: pointer;
  outline: none;
  width: 100%;
  margin-top: 20px;
  display: block;
  text-align: center;
}

.message {
  position: relative;
  margin-bottom: 80px;
}
.message-head {
  position: relative;
}
.message-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  position: absolute;
  left: 0;
  top: 0;
  z-index: 1;
}
.message-title {
  position: relative;
  z-index: 2;
  padding: 100px 40px 120px;
  color: #fff;
  font-size: 48px;
  font-weight: bold;
  text-align: center;
}
.message-con {
  display: flex;
  flex-direction: column;
  align-items: center;
}
.message-wrap {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background-color: #fff;
  box-shadow: 0px 0px 25px 0px rgba(155.99999999999997, 155.99999999999997, 155.99999999999997, 0.2);
  transition: background 0.3s, border 0.3s, border-radius 0.3s, box-shadow 0.3s;
  padding: 50px;
  align-items: center;
  position: relative;
  z-index: 2;
  margin-top: -80px;
}
.message-form {
  padding: 20px;
}
.form-item-label {
  color: var(--text-color-dark-gray);
  margin-bottom: 2px;
  letter-spacing: 1px;
}
.form-item-label::after {
  content: "*";
  color: var(--primary-color);
}

.form-item-input {
  width: 100%;
  border: 1px solid #e8e8e8;
  padding: 6px 15px;
  outline: none;
  display: block;
  line-height: 1.5px;
}
.form-item-textarea {
  width: 100%;
  border: 1px solid #e8e8e8;
  padding: 6px 15px;
  outline: none;
  display: block;
}
.form-item-input::placeholder,
.form-item-textarea::placeholder {
  color: #ccc;
}

.message-form-wrap .form-item + .form-item {
  margin-top: 10px;
}
.message-form-btn {
  padding-top: 20px;
}
.message-form-btn button {
  padding: 12px 10px;
  background: linear-gradient(150deg, #3ea3f4 0%, #1c53ff 100%);
  border: 0;
  border-radius: 4px;
  color: #fff;
  font-size: 14px;
  cursor: pointer;
  outline: none;
  width: 100%;
}
.message-desc {
  padding: 20px;
}
.message-desc-title {
  color: var(--text-color-darker);
  font-size: 34px;
  font-weight: 600;
  margin-bottom: 12px;
}
.message-desc-subtitle {
  color: var(--text-color-gray);
  line-height: 1.5;
  font-size: 14px;
}
.message-desc-subtitle li {
  list-style: none;
}
.message-desc-subtitle li + li {
  margin-top: 4px;
}

.scrollToTop {
  display: none;
  position: relative;
  z-index: 300;
}

footer {
  margin-top: 124px;
  background-color: var(--primary-color);
  display: grid;
  justify-items: center;
  padding-top: 72px;
  padding-bottom: 24px;
}

/* 底部菜单 */
.footer-menus {
  width: 100%;
  max-width: 1180px;
  display: grid;
  /* 5列布局 */
  grid-template-columns: 1fr 1fr;
  padding: 0 80px;
  position: relative;
}

/* 导航菜单，靠右对齐 */
.footer-menu {
  justify-self: center;
}

.menu-title {
  font-size: 16px;
  color: white;
  font-weight: 500;
  margin-bottom: 20px;
}

.contact-us {
  justify-self: center;
  color: #fff;
}

.contact-us p:not(:first-child) {
  padding-bottom: 16px;
}

.menu-items li {
  list-style: none;
  padding-bottom: 8px;
}
.menu-items li a {
  text-decoration: none;
  color: #fff;
}

/* 备案信息 */
.icp-info {
  margin-top: 24px;
  margin-bottom: 16px;
}

/* 备案信息，版权信息 */
.icp-info,
.rights {
  font-weight: 300;
  /* 占满整行，-1代表最后一个编号 */
  grid-column: 1 / -1;
  /* 居中对齐 */
  justify-self: center;
  color: white;
}
/* 返回顶部按钮 */
.fixed-btn {
  position: fixed;
  z-index: 3;
  bottom: 60px;
  right: 30px;
  display: flex;
  flex-direction: column;
}
.fixed-btn a,
.fixed-btn button {
  width: 42px;
  height: 42px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--primary-color);
  color: white;
  margin-top: 20px;
  border: 1px solid #fff;
  position: relative;
}
.fixed-btn a img,
.fixed-btn button img {
  width: 24px;
  height: 24px;
}

#comment_bubble {
  height: auto;
  background: #fff;
  position: absolute;
  -moz-border-radius: 12px;
  -webkit-border-radius: 12px;
  border-radius: 12px;
  padding: 15px;
  color: var(--primary-color);
  font-size: 18px;
  display: none;
  left: -162px;
  box-shadow: 0 0 18px rgba(0, 0, 0, 0.2);
  white-space: nowrap;
}

#comment_bubble:before {
  content: "";
  width: 0;
  height: 0;
  left: 100%;
  top: 30%;
  position: absolute;
  border-top: 10px solid transparent;
  border-left: 15px solid #fff;
  border-bottom: 10px solid transparent;
}

@media (max-width: 1100px) {
  header nav {
    display: none;
  }
  header {
    grid-template-columns: repeat(2, 1fr);
  }

  /* 折叠菜单样式，显示出来 */
  header .burger {
    display: block;
    justify-self: end;
    cursor: pointer;
    position: relative;
    width: 20px;
    height: 6px;
  }

  /* 折叠按钮线条样式 */
  .burger-line1,
  .burger-line2,
  .burger-line3 {
    width: 20px;
    height: 2px;
    background-color: var(--text-color-lightest);
    /* position: relative; */
  }

  /* 上移第一条线 */
  .burger-line1 {
    position: absolute;
    top: -6px;
  }
  /* 下移第三条线 */
  .burger-line3 {
    position: absolute;
    top: 6px;
  }

  /* 全屏导航展开时，折叠按钮设置为深色 */
  header.open .burger-line1,
  header.open .burger-line2,
  header.open .burger-line3,
  header.sticky .burger-line1,
  header.sticky .burger-line2,
  header.sticky .burger-line3 {
    background-color: var(--text-color-darker);
    transition: 0.4s ease;
  }

  /* 全屏导航显示时，折叠按钮第一条线样式 */
  header.open .burger-line1 {
    transform: rotate(45deg) translate(3px, 5px);
  }

  /* 全屏导航显示时，折叠按钮第二条线样式 */
  header.open .burger-line2 {
    transform: translateX(5px);
    opacity: 0;
  }

  /* 全屏导航显示时，折叠按钮第三条线样式 */
  header.open .burger-line3 {
    transform: rotate(-45deg) translate(3px, -5px);
  }
  /* 全屏导航显示时，logo样式 */
  header.open .logo {
    color: var(--text-color-darker);
    z-index: 40;
  }

  /* 全屏导航显示时，导航菜单样式 */
  header.open nav {
    display: grid;
    /* 每行高度为内容的高度，不设置会平分全屏高度 */
    grid-auto-rows: max-content;
    /* 菜单项靠右对齐 */
    justify-items: end;
    position: absolute;
    top: 0;
    left: 0;
    background: white;
    width: 100vw;
    height: 100vh;
    padding: 0 40px;
    opacity: 0;
    /* 下滑效果 */
    animation: slideDown 0.6s ease-out forwards;
  }
  /* 全屏导航显示时，导航菜单项样式和动画 */
  header.open nav > * {
    margin: 12px 4px;
    font-size: 18px;
    color: var(--text-color-darker);
    opacity: 0;
    animation: showMenu 0.5s linear forwards 0.4s;
  }

  /* 导航下滑动画 */
  @keyframes slideDown {
    from {
      height: 0;
      opacity: 0;
    }
    to {
      height: 100vh;
      padding-top: 80px;
      opacity: 1;
    }
  }

  /* 菜单项动画 */
  @keyframes showMenu {
    from {
      opacity: 0;
      transform: translateY(-1vh);
    }
    to {
      opacity: 1;
    }
  }

  section {
    padding: 0 40px;
  }
}

/* 小于992像素时 */
@media (max-width: 992px) {
  .banner-content h1 {
    font-size: 48px;
  }

  .banner-content h3 {
    font-size: 18px;
  }

  .about-wrap {
    grid-template-columns: repeat(1, 1fr);
    column-gap: 10vw;
    row-gap: 8vh;
  }
  .about-item-title {
    font-size: 20px;
  }

  .service-wrap {
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: unset;
  }

  .message-wrap {
    grid-template-columns: 1fr;
  }
}

/* 小于768像素时 */
@media (max-width: 768px) {
  .category-wrap {
    grid-template-columns: repeat(1, 1fr);
  }
  .service-wrap {
    grid-template-columns: repeat(1, 1fr);
    grid-template-rows: unset;
  }
  .footer-menus {
    grid-template-columns: 1fr;
    padding: 0 18px;
  }
  .footer-menu,
  .contact-us {
    justify-self: start;
    margin-bottom: 20px;
  }
  footer {
    padding-top: 24px;
  }
  header {
    padding: 0 24px;
  }
  .fixed-btn {
    right: 12px;
  }
}

/* 小于576像素 */
@media (max-width: 576px) {
  section {
    padding: 0 12px;
  }
  .banner-content h1 {
    font-size: 26px;
  }
  .banner-content h3 {
    font-size: 12px;
  }
  .banner-content .contact-btn {
    padding: 8px 18px;
    font-size: 14px;
  }
  .message-wrap {
    padding: 0px;
  }
  .message-title {
    font-size: 28px;
    padding: 50px 40px 120px;
  }
}