:root {
      --theme: #0B3D91;
      --theme-dark: #072b68;
      --theme-soft: #eaf1fc;
      --amber: #d99b22;
      --wax: #f4c95d;
      --brown: #3f2b1e;
      --ink: #172033;
      --muted: #687386;
      --line: #dfe4ec;
      --surface: #ffffff;
      --background: #f5f7fa;
      --success: #16855b;
      --radius: 6px;
      --shadow: 0 12px 32px rgba(19, 34, 58, 0.1);
      --container: 1180px;
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      color: var(--ink);
      background: var(--background);
      font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
      font-size: 15px;
      line-height: 1.65;
      letter-spacing: 0;
    }

    body.drawer-locked {
      overflow: hidden;
    }

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

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

    button,
    input {
      font: inherit;
    }

    button {
      color: inherit;
    }

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

    .topbar {
      color: #d9e6fa;
      background: #082d68;
      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: #ffffff;
    }

    .header {
      position: relative;
      z-index: 50;
      border-bottom: 1px solid var(--line);
      background: rgba(255, 255, 255, 0.98);
      box-shadow: 0 3px 14px rgba(23, 32, 51, 0.05);
    }

    .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;
    }

    .logo img {
      width: 42px;
      height: 42px;
      flex: 0 0 42px;
      border-radius: 6px;
      object-fit: contain;
      background: #ffffff;
    }

    .logo span {
      max-width: 170px;
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
    }

    .main-nav {
      align-self: stretch;
      margin-left: auto;
    }

    .nav-list {
      height: 100%;
      margin: 0;
      padding: 0;
      display: flex;
      align-items: stretch;
      list-style: none;
    }

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

    .nav-link {
      position: relative;
      padding: 0 13px;
      display: flex;
      align-items: center;
      color: #27344a;
      font-weight: 700;
      white-space: nowrap;
    }

    .nav-link::after {
      content: "";
      position: absolute;
      right: 13px;
      bottom: 0;
      left: 13px;
      height: 3px;
      background: var(--theme);
      transform: scaleX(0);
      transition: transform 0.2s ease;
    }

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

    .nav-link:hover::after,
    .nav-item:focus-within > .nav-link::after {
      transform: scaleX(1);
    }

    .nav-link.has-arrow {
      padding-right: 26px;
    }

    .nav-link.has-arrow::before {
      content: "";
      position: absolute;
      top: 50%;
      right: 11px;
      width: 6px;
      height: 6px;
      border-right: 2px solid currentColor;
      border-bottom: 2px solid currentColor;
      transform: translateY(-70%) rotate(45deg);
    }

    .dropdown-panel,
    .mega-menu {
      position: absolute;
      top: 100%;
      z-index: 100;
      visibility: hidden;
      border: 1px solid var(--line);
      border-top: 3px solid var(--theme);
      background: #ffffff;
      box-shadow: var(--shadow);
      opacity: 0;
      transform: translateY(8px);
      transition: opacity 0.18s ease, transform 0.18s ease, visibility 0.18s;
      pointer-events: none;
    }

    .dropdown-panel::before,
    .mega-menu::before {
      content: "";
      position: absolute;
      right: 0;
      bottom: 100%;
      left: 0;
      height: 8px;
    }

    .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;
      transform: translateY(0);
      pointer-events: auto;
    }

    .dropdown-panel {
      left: 0;
      width: 300px;
      padding: 12px;
      border-radius: 0 0 var(--radius) var(--radius);
    }

    .dropdown-panel > a {
      padding: 9px 10px;
      display: block;
      border-bottom: 1px solid #edf0f5;
      color: #344158;
    }

    .dropdown-panel > a:not(.dropdown-all) {
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
    }

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

    .dropdown-panel .dropdown-all {
      margin-top: 6px;
      border-bottom: 0;
      color: var(--theme);
      font-weight: 800;
    }

    .mega-menu {
      right: -160px;
      width: min(880px, calc(100vw - 40px));
      padding: 22px;
      border-radius: 0 0 var(--radius) var(--radius);
    }

    .mega-menu-video {
      right: -340px;
    }

    .mega-menu-tools,
    .mega-menu-products {
      right: -220px;
    }

    .mega-title {
      margin: 0 0 12px;
      color: var(--brown);
      font-size: 16px;
      font-weight: 800;
    }

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

    .mega-card {
      min-width: 0;
      min-height: 84px;
      padding: 10px;
      display: flex;
      align-items: center;
      gap: 11px;
      border: 1px solid #e7eaf0;
      border-radius: var(--radius);
      background: #ffffff;
      transition: border-color 0.18s ease, background 0.18s ease;
    }

    .mega-card:hover {
      border-color: #a9bee0;
      background: #f7faff;
    }

    .mega-card img {
      width: 54px;
      height: 54px;
      flex: 0 0 54px;
      border-radius: 5px;
      object-fit: cover;
      background: #eef2f7;
    }

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

    .mega-card strong,
    .mega-card p,
    .mega-card small {
      display: block;
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
    }

    .mega-card strong {
      color: #1b2940;
      font-size: 14px;
    }

    .mega-card p {
      margin: 3px 0;
      color: var(--muted);
      font-size: 12px;
    }

    .mega-card small {
      color: #7a8494;
      font-size: 11px;
    }

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

    .mega-categories a {
      padding: 6px 11px;
      border: 1px solid #dbe2ed;
      border-radius: 4px;
      color: #445168;
      background: #f8fafc;
      font-size: 13px;
    }

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

    .mega-footer {
      margin-top: 15px;
      padding-top: 12px;
      display: block;
      border-top: 1px solid var(--line);
      color: var(--theme);
      font-weight: 800;
      text-align: right;
    }

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

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

    .header-account {
      min-height: 38px;
      padding: 7px 15px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border-radius: 4px;
      color: #ffffff;
      background: var(--theme);
      font-weight: 800;
      white-space: nowrap;
    }

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

    .hamburger {
      width: 42px;
      height: 42px;
      padding: 10px;
      display: none;
      border: 1px solid #ccd5e2;
      border-radius: 4px;
      background: #ffffff;
      cursor: pointer;
    }

    .hamburger span {
      width: 100%;
      height: 2px;
      margin: 4px 0;
      display: block;
      background: var(--theme-dark);
      transition: transform 0.2s ease, opacity 0.2s ease;
    }

    .hamburger.active span:nth-child(1) {
      transform: translateY(6px) rotate(45deg);
    }

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

    .hamburger.active span:nth-child(3) {
      transform: translateY(-6px) rotate(-45deg);
    }

    .drawer-overlay {
      position: fixed;
      inset: 0;
      z-index: 190;
      visibility: hidden;
      background: rgba(10, 19, 34, 0.62);
      opacity: 0;
      transition: opacity 0.2s ease, visibility 0.2s;
    }

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

    .mobile-drawer {
      position: fixed;
      top: 0;
      right: 0;
      bottom: 0;
      z-index: 200;
      width: min(390px, 92vw);
      overflow-y: auto;
      background: #ffffff;
      box-shadow: -12px 0 36px rgba(0, 0, 0, 0.2);
      transform: translateX(104%);
      transition: transform 0.25s ease;
    }

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

    .drawer-head {
      min-height: 72px;
      padding: 14px 16px;
      display: flex;
      align-items: center;
      gap: 12px;
      border-bottom: 1px solid var(--line);
      background: #f8fafc;
    }

    .member-drawer {
      min-width: 0;
      flex: 1;
    }

    .drawer-head > a {
      padding: 7px 12px;
      border-radius: 4px;
      color: #ffffff;
      background: var(--theme);
      font-weight: 800;
    }

    .drawer-close {
      width: 38px;
      height: 38px;
      border: 1px solid #d6dce6;
      border-radius: 4px;
      background: #ffffff;
      font-size: 25px;
      line-height: 1;
      cursor: pointer;
    }

    .drawer-menu {
      padding: 12px 16px 28px;
    }

    .drawer-link,
    .drawer-toggle {
      width: 100%;
      min-height: 48px;
      padding: 11px 8px;
      display: flex;
      align-items: center;
      border: 0;
      border-bottom: 1px solid #e9edf3;
      background: transparent;
      color: #26354d;
      font-weight: 800;
      text-align: left;
      cursor: pointer;
    }

    .drawer-toggle {
      position: relative;
      padding-right: 34px;
    }

    .drawer-toggle::after {
      content: "+";
      position: absolute;
      right: 9px;
      color: var(--theme);
      font-size: 21px;
      font-weight: 400;
    }

    .drawer-toggle.active::after {
      content: "−";
    }

    .drawer-submenu {
      display: none;
      padding: 7px 0 10px 14px;
      border-bottom: 1px solid #e9edf3;
      background: #f8fafc;
    }

    .drawer-submenu.open {
      display: block;
    }

    .drawer-submenu a {
      padding: 8px 10px;
      display: block;
      color: #536078;
      overflow-wrap: anywhere;
    }

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

    .video-page {
      min-width: 0;
    }

    .video-page .video-heading {
      position: relative;
      overflow: hidden;
      color: #ffffff;
      background:
        linear-gradient(rgba(7, 43, 104, 0.92), rgba(11, 61, 145, 0.92)),
        #0B3D91;
    }

    .video-page .video-heading::after {
      content: "";
      position: absolute;
      right: 6%;
      bottom: -56px;
      width: 220px;
      height: 190px;
      border: 28px solid rgba(244, 201, 93, 0.18);
      transform: rotate(18deg);
    }

    .video-page .video-heading-inner {
      position: relative;
      z-index: 1;
      padding: 58px 0 50px;
    }

    .video-page .breadcrumb {
      margin-bottom: 17px;
      display: flex;
      align-items: center;
      flex-wrap: wrap;
      gap: 8px;
      color: #c9d8f0;
      font-size: 13px;
    }

    .video-page .breadcrumb a:hover {
      color: #ffffff;
    }

    .video-page .video-heading h1 {
      max-width: 820px;
      margin: 0;
      color: #ffffff;
      font-size: clamp(30px, 4vw, 48px);
      line-height: 1.2;
      letter-spacing: 0;
      overflow-wrap: anywhere;
    }

    .video-page .video-heading p {
      max-width: 760px;
      margin: 15px 0 0;
      color: #dce7f7;
      font-size: 16px;
    }

    .video-page .video-library {
      padding: 42px 0 68px;
    }

    .video-page .category-panel {
      margin-bottom: 28px;
      padding: 20px;
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: var(--surface);
    }

    .video-page .section-kicker {
      margin: 0 0 12px;
      color: var(--brown);
      font-size: 14px;
      font-weight: 800;
    }

    .video-page .category-links {
      display: flex;
      flex-wrap: wrap;
      gap: 9px;
    }

    .video-page .category-links a {
      min-height: 38px;
      padding: 7px 14px;
      display: inline-flex;
      align-items: center;
      border: 1px solid #d6deea;
      border-radius: 4px;
      color: #334159;
      background: #f9fafc;
      font-weight: 700;
      transition: color 0.18s ease, border-color 0.18s ease, background 0.18s ease;
    }

    .video-page .category-links a:hover {
      border-color: var(--theme);
      color: var(--theme);
      background: var(--theme-soft);
    }

    .video-page .library-toolbar {
      margin-bottom: 20px;
      display: flex;
      align-items: end;
      justify-content: space-between;
      gap: 20px;
    }

    .video-page .library-toolbar h2 {
      margin: 0;
      color: var(--ink);
      font-size: 25px;
      line-height: 1.3;
    }

    .video-page .library-toolbar p {
      margin: 5px 0 0;
      color: var(--muted);
    }

    .video-page .library-note {
      padding: 7px 11px;
      border-left: 3px solid var(--amber);
      color: #66512a;
      background: #fff9e8;
      font-size: 13px;
      white-space: nowrap;
    }

    .video-page .video-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 20px;
    }

    .video-page .video-card {
      min-width: 0;
      overflow: hidden;
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: var(--surface);
      box-shadow: 0 7px 20px rgba(25, 38, 61, 0.06);
      transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
    }

    .video-page .video-card:hover {
      border-color: #b8c9e3;
      box-shadow: 0 14px 30px rgba(25, 38, 61, 0.12);
      transform: translateY(-3px);
    }

    .video-page .video-cover {
      position: relative;
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #172033;
    }

    .video-page .video-cover img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.3s ease;
    }

    .video-page .video-card:hover .video-cover img {
      transform: scale(1.035);
    }

    .video-page .play-mark {
      position: absolute;
      top: 50%;
      left: 50%;
      width: 50px;
      height: 50px;
      border: 2px solid rgba(255, 255, 255, 0.9);
      border-radius: 50%;
      background: rgba(11, 61, 145, 0.9);
      transform: translate(-50%, -50%);
      transition: background 0.18s ease;
    }

    .video-page .play-mark::after {
      content: "";
      position: absolute;
      top: 50%;
      left: 52%;
      width: 0;
      height: 0;
      border-top: 8px solid transparent;
      border-bottom: 8px solid transparent;
      border-left: 13px solid #ffffff;
      transform: translate(-40%, -50%);
    }

    .video-page .video-card:hover .play-mark {
      background: var(--amber);
    }

    .video-page .duration {
      position: absolute;
      right: 9px;
      bottom: 9px;
      padding: 3px 7px;
      border-radius: 3px;
      color: #ffffff;
      background: rgba(20, 24, 31, 0.86);
      font-size: 12px;
      line-height: 1.4;
    }

    .video-page .video-card-body {
      padding: 17px;
    }

    .video-page .video-card-body h3 {
      min-height: 48px;
      margin: 0 0 9px;
      color: #17233a;
      font-size: 17px;
      line-height: 1.42;
      overflow-wrap: anywhere;
    }

    .video-page .video-card-body p {
      min-height: 48px;
      margin: 0 0 14px;
      display: -webkit-box;
      overflow: hidden;
      color: var(--muted);
      font-size: 14px;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .video-page .video-meta {
      padding-top: 12px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 10px;
      border-top: 1px solid #edf0f4;
      color: #7a8494;
      font-size: 12px;
    }

    .video-page .watch-link {
      color: var(--theme);
      font-weight: 800;
    }

    .video-page .pagination {
      margin-top: 34px;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-wrap: wrap;
      gap: 7px;
    }

    .video-page .pagination a {
      min-width: 40px;
      min-height: 40px;
      padding: 7px 12px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: 1px solid #d6deea;
      border-radius: 4px;
      color: #3f4d64;
      background: #ffffff;
      font-weight: 700;
    }

    .video-page .pagination a:hover,
    .video-page .pagination a.active,
    .video-page .pagination a.current {
      border-color: var(--theme);
      color: #ffffff;
      background: var(--theme);
    }

    .video-page .learning-cta {
      margin-top: 46px;
      padding: 28px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 25px;
      border-left: 5px solid var(--wax);
      border-radius: var(--radius);
      color: #ffffff;
      background: var(--brown);
    }

    .video-page .learning-cta h2 {
      margin: 0 0 6px;
      color: #ffffff;
      font-size: 22px;
    }

    .video-page .learning-cta p {
      max-width: 700px;
      margin: 0;
      color: #e8ddcf;
    }

    .video-page .learning-cta a {
      min-height: 42px;
      padding: 9px 17px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border-radius: 4px;
      color: var(--brown);
      background: var(--wax);
      font-weight: 800;
      white-space: nowrap;
    }

    .footer {
      color: #cbd5e4;
      background: #111a2a;
    }

    .footer-main {
      padding: 54px 0 40px;
      display: grid;
      grid-template-columns: 1.45fr 1fr 1fr 1fr;
      gap: 38px;
    }

    .footer .logo {
      color: #ffffff;
    }

    .footer-brand p {
      max-width: 390px;
      margin: 18px 0 0;
      color: #aeb9ca;
    }

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

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

    .footer-links a:hover,
    .footer-contact a:hover {
      color: var(--wax);
    }

    .footer-contact p {
      margin: 0 0 9px;
      overflow-wrap: anywhere;
    }

    .footer-bottom {
      min-height: 64px;
      padding: 16px 0;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
      border-top: 1px solid #2a3547;
      color: #929fb3;
      font-size: 13px;
    }

    @media (max-width: 1120px) {
      .main-nav {
        display: none;
      }

      .hamburger {
        display: block;
      }

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

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

    @media (max-width: 820px) {
      .container {
        width: min(100% - 28px, var(--container));
      }

      .topbar-inner {
        padding: 7px 0;
        align-items: flex-start;
      }

      .topbar-contact {
        align-items: flex-end;
        flex-direction: column;
        gap: 2px;
      }

      .header-inner {
        min-height: 68px;
      }

      .header .logo span {
        max-width: 135px;
      }

      .member-entry {
        display: none;
      }

      .video-page .video-heading-inner {
        padding: 43px 0 39px;
      }

      .video-page .library-toolbar {
        align-items: flex-start;
        flex-direction: column;
      }

      .video-page .library-note {
        white-space: normal;
      }

      .video-page .learning-cta {
        align-items: flex-start;
        flex-direction: column;
      }

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

    @media (max-width: 560px) {
      .topbar-inner {
        display: block;
      }

      .topbar-contact {
        margin-top: 4px;
        align-items: flex-start;
      }

      .header-account {
        padding: 7px 11px;
      }

      .header .logo img {
        width: 38px;
        height: 38px;
        flex-basis: 38px;
      }

      .header .logo span {
        max-width: 112px;
        font-size: 16px;
      }

      .video-page .video-heading h1 {
        font-size: 30px;
      }

      .video-page .video-library {
        padding: 28px 0 48px;
      }

      .video-page .category-panel {
        padding: 15px;
      }

      .video-page .category-links {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
      }

      .video-page .category-links a {
        justify-content: center;
        text-align: center;
        overflow-wrap: anywhere;
      }

      .video-page .video-grid {
        grid-template-columns: minmax(0, 1fr);
      }

      .video-page .video-card-body h3,
      .video-page .video-card-body p {
        min-height: 0;
      }

      .video-page .learning-cta {
        padding: 22px;
      }

      .footer-main {
        grid-template-columns: minmax(0, 1fr);
        gap: 28px;
      }

      .footer-bottom {
        align-items: flex-start;
        flex-direction: column;
        gap: 5px;
      }
    }