:root {
      --theme: #0B3D91;
      --theme-dark: #072b68;
      --theme-soft: #eaf1fc;
      --ink: #172033;
      --muted: #687386;
      --line: #dfe5ee;
      --surface: #ffffff;
      --page: #f5f7fa;
      --amber: #e4a11b;
      --danger: #c73b35;
      --shadow: 0 12px 32px rgba(20, 32, 51, .1);
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      color: var(--ink);
      background: var(--page);
      font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
      line-height: 1.65;
      letter-spacing: 0;
    }

    body.drawer-locked {
      overflow: hidden;
    }

    img,
    video,
    iframe {
      display: block;
      max-width: 100%;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    button,
    input,
    textarea,
    select {
      font: inherit;
    }

    button {
      color: inherit;
    }

    .container {
      width: min(1180px, calc(100% - 40px));
      margin: 0 auto;
    }

    .topbar {
      color: #dce8fb;
      background: #071a38;
      font-size: 13px;
    }

    .topbar-inner {
      min-height: 36px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
    }

    .topbar-contact {
      display: flex;
      align-items: center;
      gap: 22px;
    }

    .topbar a:hover {
      color: #fff;
    }

    .header {
      position: relative;
      z-index: 50;
      background: var(--surface);
      border-bottom: 1px solid var(--line);
    }

    .header-inner {
      min-height: 76px;
      display: flex;
      align-items: center;
      gap: 24px;
    }

    .logo {
      min-width: 0;
      display: inline-flex;
      align-items: center;
      gap: 10px;
      color: var(--theme-dark);
      font-size: 19px;
      font-weight: 800;
      white-space: nowrap;
    }

    .logo img {
      width: 38px;
      height: 38px;
      flex: 0 0 38px;
      object-fit: contain;
    }

    .main-nav {
      min-width: 0;
      margin-left: auto;
    }

    .nav-list {
      display: flex;
      align-items: stretch;
      gap: 2px;
      margin: 0;
      padding: 0;
      list-style: none;
    }

    .nav-item {
      position: relative;
      display: flex;
      align-items: center;
    }

    .nav-link {
      min-height: 76px;
      display: inline-flex;
      align-items: center;
      padding: 0 11px;
      color: #29354a;
      font-size: 15px;
      font-weight: 700;
      white-space: nowrap;
    }

    .nav-link:hover,
    .nav-item:focus-within > .nav-link {
      color: var(--theme);
    }

    .has-arrow::after {
      width: 6px;
      height: 6px;
      margin: -4px 0 0 7px;
      border-right: 1.5px solid currentColor;
      border-bottom: 1.5px solid currentColor;
      content: "";
      transform: rotate(45deg);
    }

    .dropdown-panel,
    .mega-menu {
      position: absolute;
      top: 100%;
      z-index: 80;
      visibility: hidden;
      opacity: 0;
      pointer-events: none;
      transform: translateY(8px);
      transition: opacity .18s ease, transform .18s ease, visibility .18s ease;
      background: var(--surface);
      border: 1px solid var(--line);
      border-top: 3px solid var(--theme);
      box-shadow: var(--shadow);
    }

    .nav-item:hover > .dropdown-panel,
    .nav-item:hover > .mega-menu,
    .nav-item:focus-within > .dropdown-panel,
    .nav-item:focus-within > .mega-menu {
      visibility: visible;
      opacity: 1;
      pointer-events: auto;
      transform: translateY(0);
    }

    .dropdown-panel {
      left: 0;
      width: 290px;
      padding: 10px;
    }

    .dropdown-panel > a {
      display: block;
      padding: 10px 12px;
      border-bottom: 1px solid #edf0f5;
      color: #344057;
      font-size: 14px;
    }

    .dropdown-panel > a:hover {
      color: var(--theme);
      background: var(--theme-soft);
    }

    .dropdown-panel .dropdown-all {
      margin-top: 6px;
      color: var(--theme);
      font-weight: 700;
      border-bottom: 0;
    }

    .mega-menu {
      left: 50%;
      width: min(760px, calc(100vw - 40px));
      padding: 20px;
      transform: translate(-50%, 8px);
    }

    .nav-item:hover > .mega-menu,
    .nav-item:focus-within > .mega-menu {
      transform: translate(-50%, 0);
    }

    .mega-menu-products,
    .mega-menu-video {
      width: min(860px, calc(100vw - 40px));
    }

    .mega-title {
      margin: 0 0 12px;
      color: var(--theme-dark);
      font-size: 15px;
      font-weight: 800;
    }

    .mega-categories {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-bottom: 15px;
    }

    .mega-categories a {
      padding: 6px 10px;
      color: #354158;
      background: #f1f4f8;
      border-radius: 4px;
      font-size: 13px;
    }

    .mega-categories a:hover {
      color: #fff;
      background: var(--theme);
    }

    .mega-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 10px;
    }

    .mega-card {
      min-width: 0;
      display: flex;
      align-items: flex-start;
      gap: 10px;
      padding: 10px;
      border: 1px solid #e8ecf2;
      border-radius: 6px;
      transition: border-color .18s ease, background .18s ease;
    }

    .mega-card:hover {
      border-color: #afc5ea;
      background: var(--theme-soft);
    }

    .mega-card img {
      width: 52px;
      height: 52px;
      flex: 0 0 52px;
      object-fit: cover;
      background: #eef2f7;
      border-radius: 4px;
    }

    .mega-card span {
      min-width: 0;
    }

    .mega-card strong,
    .mega-card p,
    .mega-card small {
      display: block;
      overflow: hidden;
    }

    .mega-card strong {
      color: #202c42;
      font-size: 14px;
      white-space: nowrap;
      text-overflow: ellipsis;
    }

    .mega-card p {
      display: -webkit-box;
      margin: 3px 0;
      color: var(--muted);
      font-size: 12px;
      line-height: 1.45;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .mega-card small {
      color: #7b8494;
      font-size: 11px;
      line-height: 1.5;
      white-space: nowrap;
      text-overflow: ellipsis;
    }

    .mega-footer {
      display: block;
      margin-top: 14px;
      padding-top: 12px;
      color: var(--theme);
      border-top: 1px solid var(--line);
      font-size: 14px;
      font-weight: 800;
      text-align: right;
    }

    .header-btns {
      display: flex;
      align-items: center;
      gap: 9px;
      white-space: nowrap;
    }

    .member-entry {
      display: inline-flex;
      align-items: center;
    }

    .header-account {
      display: inline-flex;
      min-height: 38px;
      align-items: center;
      justify-content: center;
      padding: 0 15px;
      color: #fff;
      background: var(--theme);
      border-radius: 5px;
      font-size: 14px;
      font-weight: 700;
    }

    .header-account:hover {
      background: var(--theme-dark);
    }

    .hamburger {
      width: 42px;
      height: 42px;
      display: none;
      align-items: center;
      justify-content: center;
      flex-direction: column;
      gap: 5px;
      padding: 0;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 5px;
      cursor: pointer;
    }

    .hamburger span {
      width: 20px;
      height: 2px;
      background: var(--ink);
      transition: transform .2s ease, opacity .2s ease;
    }

    .hamburger.active span:nth-child(1) {
      transform: translateY(7px) rotate(45deg);
    }

    .hamburger.active span:nth-child(2) {
      opacity: 0;
    }

    .hamburger.active span:nth-child(3) {
      transform: translateY(-7px) rotate(-45deg);
    }

    .drawer-overlay {
      position: fixed;
      inset: 0;
      z-index: 90;
      visibility: hidden;
      opacity: 0;
      background: rgba(8, 16, 29, .58);
      transition: opacity .22s ease, visibility .22s ease;
    }

    .drawer-overlay.open {
      visibility: visible;
      opacity: 1;
    }

    .mobile-drawer {
      position: fixed;
      top: 0;
      right: 0;
      z-index: 100;
      width: min(390px, 90vw);
      height: 100vh;
      overflow-y: auto;
      background: #fff;
      box-shadow: -18px 0 50px rgba(0, 0, 0, .18);
      transform: translateX(105%);
      transition: transform .24s ease;
    }

    .mobile-drawer.open {
      transform: translateX(0);
    }

    .drawer-head {
      min-height: 70px;
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 13px 18px;
      color: #fff;
      background: var(--theme-dark);
    }

    .member-drawer {
      min-width: 0;
      margin-right: auto;
    }

    .drawer-head > a {
      padding: 7px 12px;
      color: var(--theme-dark);
      background: #fff;
      border-radius: 4px;
      font-size: 14px;
      font-weight: 700;
    }

    .drawer-close {
      width: 36px;
      height: 36px;
      padding: 0;
      color: #fff;
      background: transparent;
      border: 1px solid rgba(255, 255, 255, .45);
      border-radius: 4px;
      font-size: 25px;
      line-height: 1;
      cursor: pointer;
    }

    .drawer-menu {
      padding: 12px 18px 28px;
    }

    .drawer-link,
    .drawer-toggle {
      width: 100%;
      min-height: 48px;
      display: flex;
      align-items: center;
      padding: 10px 4px;
      color: #253149;
      background: transparent;
      border: 0;
      border-bottom: 1px solid var(--line);
      font-weight: 700;
      text-align: left;
      cursor: pointer;
    }

    .drawer-toggle {
      justify-content: space-between;
    }

    .drawer-toggle::after {
      width: 8px;
      height: 8px;
      margin-right: 5px;
      border-right: 2px solid var(--theme);
      border-bottom: 2px solid var(--theme);
      content: "";
      transform: rotate(45deg);
      transition: transform .2s ease;
    }

    .drawer-toggle.active::after {
      transform: rotate(225deg);
    }

    .drawer-submenu {
      max-height: 0;
      overflow: hidden;
      background: #f6f8fb;
      transition: max-height .25s ease;
    }

    .drawer-submenu.open {
      max-height: 720px;
    }

    .drawer-submenu a {
      display: block;
      padding: 9px 14px;
      color: #526078;
      border-bottom: 1px solid #e8ecf2;
      font-size: 14px;
    }

    .drawer-submenu a:hover {
      color: var(--theme);
    }

    .video-detail-main {
      min-width: 0;
      padding: 36px 0 72px;
    }

    .video-detail-main .video-breadcrumb {
      margin-bottom: 18px;
      color: var(--muted);
      font-size: 14px;
    }

    .video-detail-main .video-breadcrumb a {
      color: var(--theme);
    }

    .video-detail-main .video-header {
      max-width: 940px;
      margin-bottom: 22px;
    }

    .video-detail-main .video-kicker {
      display: inline-flex;
      align-items: center;
      gap: 7px;
      margin-bottom: 8px;
      color: var(--theme);
      font-size: 13px;
      font-weight: 800;
    }

    .video-detail-main .video-kicker::before {
      width: 9px;
      height: 9px;
      background: var(--danger);
      border-radius: 50%;
      content: "";
    }

    .video-detail-main h1 {
      margin: 0;
      color: #111a2b;
      font-size: clamp(28px, 4vw, 44px);
      line-height: 1.25;
      letter-spacing: 0;
    }

    .video-detail-main .video-meta {
      display: flex;
      flex-wrap: wrap;
      gap: 9px 20px;
      margin-top: 14px;
      color: var(--muted);
      font-size: 14px;
    }

    .video-detail-main .video-stage {
      overflow: hidden;
      color: #fff;
      background: #090d14;
      border-radius: 6px;
      box-shadow: 0 20px 50px rgba(9, 13, 20, .2);
    }

    .video-detail-main .video-player {
      width: 100%;
      min-height: 320px;
      aspect-ratio: 16 / 9;
      display: grid;
      place-items: center;
      overflow: hidden;
      background: #05070b;
    }

    .video-detail-main .video-player > * {
      max-width: 100%;
    }

    .video-detail-main .video-player iframe,
    .video-detail-main .video-player video {
      width: 100%;
      height: 100%;
      border: 0;
    }

    .video-detail-main .video-stage-caption {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
      padding: 14px 18px;
      color: #c9d0dc;
      background: #111722;
      font-size: 13px;
    }

    .video-detail-main .video-layout {
      min-width: 0;
      display: grid;
      grid-template-columns: minmax(0, 1fr) 320px;
      gap: 28px;
      margin-top: 30px;
      align-items: start;
    }

    .video-detail-main .video-article,
    .video-detail-main .related-panel {
      min-width: 0;
      background: var(--surface);
      border: 1px solid var(--line);
      border-radius: 6px;
    }

    .video-detail-main .video-article {
      padding: 28px;
    }

    .video-detail-main .section-title {
      margin: 0 0 16px;
      color: #172033;
      font-size: 22px;
      line-height: 1.35;
    }

    .video-detail-main .video-summary {
      margin: 0 0 24px;
      padding: 16px 18px;
      color: #354158;
      background: var(--theme-soft);
      border-left: 4px solid var(--theme);
    }

    .video-detail-main .video-content {
      min-width: 0;
      max-width: 100%;
      overflow-x: auto;
      color: #344057;
    }

    .video-detail-main .video-content img,
    .video-detail-main .video-content table,
    .video-detail-main .video-content iframe,
    .video-detail-main .video-content video {
      max-width: 100%;
    }

    .video-detail-main .video-content table {
      width: 100%;
      border-collapse: collapse;
    }

    .video-detail-main .video-content th,
    .video-detail-main .video-content td {
      padding: 10px;
      border: 1px solid var(--line);
    }

    .video-detail-main .video-tags {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 8px;
      margin-top: 28px;
      padding-top: 20px;
      border-top: 1px solid var(--line);
      color: var(--muted);
      font-size: 14px;
    }

    .video-detail-main .video-tags-content {
      color: var(--theme);
      font-weight: 700;
    }

    .video-detail-main .video-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 22px;
    }

    .video-detail-main .action-link {
      min-height: 42px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0 17px;
      color: #fff;
      background: var(--theme);
      border-radius: 5px;
      font-weight: 700;
    }

    .video-detail-main .action-link.secondary {
      color: var(--theme);
      background: #fff;
      border: 1px solid var(--theme);
    }

    .video-detail-main .related-panel {
      padding: 20px;
    }

    .video-detail-main .related-list {
      display: grid;
      gap: 14px;
    }

    .video-detail-main .related-video {
      display: block;
      overflow: hidden;
      border: 1px solid #e7ebf1;
      border-radius: 5px;
      transition: border-color .18s ease, transform .18s ease;
    }

    .video-detail-main .related-video:hover {
      border-color: #a9c0e5;
      transform: translateY(-2px);
    }

    .video-detail-main .related-cover {
      position: relative;
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #101722;
    }

    .video-detail-main .related-cover img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }

    .video-detail-main .related-duration {
      position: absolute;
      right: 7px;
      bottom: 7px;
      padding: 2px 7px;
      color: #fff;
      background: rgba(0, 0, 0, .76);
      border-radius: 3px;
      font-size: 12px;
    }

    .video-detail-main .related-body {
      padding: 11px 12px 12px;
    }

    .video-detail-main .related-body strong {
      display: -webkit-box;
      overflow: hidden;
      color: #202b40;
      font-size: 14px;
      line-height: 1.5;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .video-detail-main .related-body p {
      display: -webkit-box;
      overflow: hidden;
      margin: 5px 0 0;
      color: var(--muted);
      font-size: 12px;
      line-height: 1.5;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .video-detail-main .more-videos {
      width: 100%;
      min-height: 42px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      margin-top: 16px;
      color: var(--theme);
      border: 1px solid var(--theme);
      border-radius: 5px;
      font-weight: 700;
    }

    .footer {
      color: #d4deed;
      background: #091a33;
    }

    .footer-main {
      display: grid;
      grid-template-columns: 1.45fr 1fr 1fr 1.1fr;
      gap: 42px;
      padding-top: 52px;
      padding-bottom: 42px;
    }

    .footer .logo {
      color: #fff;
    }

    .footer-brand p {
      max-width: 390px;
      margin: 18px 0 0;
      color: #aebbd0;
      font-size: 14px;
    }

    .footer h3 {
      margin: 4px 0 15px;
      color: #fff;
      font-size: 16px;
    }

    .footer-links {
      display: grid;
      gap: 8px;
    }

    .footer-links a,
    .footer-contact a {
      color: #b9c6d9;
      font-size: 14px;
    }

    .footer-links a:hover,
    .footer-contact a:hover {
      color: #fff;
    }

    .footer-contact p {
      margin: 0 0 9px;
      color: #b9c6d9;
      font-size: 14px;
      overflow-wrap: anywhere;
    }

    .footer-bottom {
      min-height: 66px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
      color: #93a4bc;
      border-top: 1px solid rgba(255, 255, 255, .12);
      font-size: 13px;
    }

    @media (max-width: 1100px) {
      .main-nav {
        display: none;
      }

      .hamburger {
        display: flex;
      }

      .header-btns {
        margin-left: auto;
      }

      .footer-main {
        grid-template-columns: repeat(2, minmax(0, 1fr));
      }
    }

    @media (max-width: 820px) {
      .video-detail-main {
        padding-top: 24px;
      }

      .video-detail-main .video-layout {
        grid-template-columns: 1fr;
      }

      .video-detail-main .related-list {
        grid-template-columns: repeat(2, minmax(0, 1fr));
      }

      .video-detail-main .related-panel {
        order: 2;
      }
    }

    @media (max-width: 640px) {
      .container {
        width: min(100% - 28px, 1180px);
      }

      .topbar-inner {
        min-height: 42px;
        align-items: flex-start;
        flex-direction: column;
        justify-content: center;
        gap: 1px;
        padding: 5px 0;
      }

      .topbar-contact {
        width: 100%;
        justify-content: space-between;
        gap: 10px;
      }

      .topbar-contact a {
        overflow-wrap: anywhere;
      }

      .header-inner {
        min-height: 66px;
        gap: 10px;
      }

      .header .logo span {
        max-width: 125px;
        overflow: hidden;
        text-overflow: ellipsis;
      }

      .member-entry {
        display: none;
      }

      .header-account {
        min-height: 36px;
        padding: 0 12px;
      }

      .video-detail-main h1 {
        font-size: 29px;
      }

      .video-detail-main .video-player {
        min-height: 190px;
      }

      .video-detail-main .video-stage-caption {
        align-items: flex-start;
        flex-direction: column;
        gap: 3px;
      }

      .video-detail-main .video-article {
        padding: 20px 17px;
      }

      .video-detail-main .related-list {
        grid-template-columns: 1fr;
      }

      .footer-main {
        grid-template-columns: 1fr;
        gap: 28px;
        padding-top: 40px;
      }

      .footer-bottom {
        align-items: flex-start;
        flex-direction: column;
        justify-content: center;
        gap: 4px;
        padding: 16px 0;
      }
    }

    @media (max-width: 420px) {
      .topbar-contact {
        display: grid;
      }

      .header .logo img {
        width: 34px;
        height: 34px;
        flex-basis: 34px;
      }

      .header .logo span {
        max-width: 100px;
        font-size: 16px;
      }

      .video-detail-main .video-meta {
        display: grid;
        gap: 5px;
      }
    }