:root {
      --theme: #0B3D91;
      --theme-dark: #072a65;
      --theme-soft: #edf4ff;
      --accent: #d4146d;
      --accent-dark: #a90d55;
      --ink: #162033;
      --muted: #667085;
      --line: #e4e7ec;
      --surface: #ffffff;
      --page: #f5f7fa;
      --success: #16794a;
      --shadow: 0 12px 32px rgba(16, 24, 40, .09);
      --container: 1200px;
    }

    * {
      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-lock {
      overflow: hidden;
    }

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

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

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

    button {
      color: inherit;
    }

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

    .topbar {
      color: #dbe8ff;
      background: #071a3c;
      font-size: 13px;
    }

    .topbar-inner {
      min-height: 36px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 24px;
    }

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

    .topbar a {
      transition: color .2s ease;
    }

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

    .header {
      position: relative;
      z-index: 50;
      background: rgba(255, 255, 255, .98);
      border-bottom: 1px solid var(--line);
    }

    .header-inner {
      min-height: 76px;
      display: flex;
      align-items: center;
      gap: 26px;
    }

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

    .logo img {
      width: 40px;
      height: 40px;
      flex: 0 0 40px;
      object-fit: contain;
      border-radius: 6px;
    }

    .logo span {
      max-width: 190px;
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
      font-size: 18px;
    }

    .main-nav {
      flex: 1;
      align-self: stretch;
    }

    .nav-list {
      height: 100%;
      margin: 0;
      padding: 0;
      display: flex;
      align-items: stretch;
      justify-content: center;
      gap: 2px;
      list-style: none;
    }

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

    .nav-link {
      height: 100%;
      padding: 0 13px;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-size: 15px;
      font-weight: 650;
      white-space: nowrap;
      transition: color .2s ease;
    }

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

    .nav-link.active {
      color: var(--theme);
    }

    .nav-link.active::after {
      content: "";
      position: absolute;
      right: 13px;
      bottom: 0;
      left: 13px;
      height: 3px;
      background: var(--accent);
    }

    .nav-link.has-arrow::before {
      content: "";
      width: 6px;
      height: 6px;
      order: 2;
      border-right: 1.5px solid currentColor;
      border-bottom: 1.5px solid currentColor;
      transform: rotate(45deg) translateY(-2px);
    }

    .dropdown-panel,
    .mega-menu {
      position: absolute;
      top: 100%;
      left: 50%;
      z-index: 60;
      visibility: hidden;
      opacity: 0;
      transform: translate(-50%, 8px);
      pointer-events: none;
      background: var(--surface);
      border: 1px solid var(--line);
      border-top: 3px solid var(--accent);
      box-shadow: var(--shadow);
      transition: opacity .18s ease, transform .18s ease, visibility .18s;
    }

    .dropdown-panel::before,
    .mega-menu::before {
      content: "";
      position: absolute;
      right: 0;
      bottom: 100%;
      left: 0;
      height: 12px;
    }

    .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: translate(-50%, 0);
      pointer-events: auto;
    }

    .dropdown-panel {
      width: 290px;
      padding: 10px;
      border-radius: 0 0 6px 6px;
    }

    .dropdown-panel a {
      display: block;
      padding: 10px 12px;
      overflow: hidden;
      color: #344054;
      border-radius: 4px;
      text-overflow: ellipsis;
      white-space: nowrap;
      font-size: 14px;
    }

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

    .dropdown-panel a:last-child {
      margin-top: 7px;
      color: var(--theme);
      font-weight: 700;
      border-top: 1px solid var(--line);
      border-radius: 0;
    }

    .mega-menu {
      width: min(760px, calc(100vw - 40px));
      padding: 20px;
      border-radius: 0 0 7px 7px;
    }

    .mega-menu-wide {
      width: min(900px, calc(100vw - 40px));
    }

    .nav-item:nth-last-child(-n+3) .mega-menu {
      right: -90px;
      left: auto;
      transform: translateY(8px);
    }

    .nav-item:nth-last-child(-n+3):hover > .mega-menu,
    .nav-item:nth-last-child(-n+3):focus-within > .mega-menu {
      transform: translateY(0);
    }

    .mega-head {
      margin-bottom: 15px;
      padding-bottom: 12px;
      display: flex;
      align-items: baseline;
      justify-content: space-between;
      gap: 18px;
      border-bottom: 1px solid var(--line);
    }

    .mega-head strong {
      color: var(--theme-dark);
      font-size: 17px;
    }

    .mega-head span {
      color: var(--muted);
      font-size: 13px;
    }

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

    .mega-category-list a {
      padding: 5px 10px;
      color: #475467;
      background: #f2f4f7;
      border-radius: 4px;
      font-size: 13px;
    }

    .mega-category-list a:hover {
      color: var(--accent-dark);
      background: #fff0f6;
    }

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

    .mega-card {
      min-width: 0;
      min-height: 82px;
      padding: 10px;
      display: flex;
      align-items: flex-start;
      gap: 10px;
      border: 1px solid var(--line);
      border-radius: 6px;
      transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
    }

    .mega-card:hover {
      border-color: #b7caec;
      box-shadow: 0 6px 18px rgba(11, 61, 145, .1);
      transform: translateY(-2px);
    }

    .mega-card > img {
      width: 54px;
      height: 54px;
      flex: 0 0 54px;
      object-fit: cover;
      background: #eef2f6;
      border-radius: 5px;
    }

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

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

    .mega-card-body strong {
      color: #1d2939;
      white-space: nowrap;
      font-size: 14px;
    }

    .mega-card-body p {
      height: 38px;
      margin: 4px 0;
      color: var(--muted);
      font-size: 12px;
      line-height: 19px;
    }

    .mega-card-body small {
      color: #667085;
      white-space: nowrap;
      font-size: 11px;
    }

    .mega-footer {
      margin-top: 14px;
      padding: 10px 12px 0;
      display: block;
      color: var(--theme);
      border-top: 1px solid var(--line);
      text-align: right;
      font-size: 13px;
      font-weight: 700;
    }

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

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

    .account-entry {
      min-height: 38px;
      padding: 8px 15px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #ffffff;
      background: var(--theme);
      border-radius: 5px;
      font-weight: 700;
      transition: background .2s ease;
    }

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

    .hamburger {
      width: 42px;
      height: 42px;
      padding: 10px;
      display: none;
      flex-direction: column;
      align-items: stretch;
      justify-content: center;
      gap: 5px;
      background: transparent;
      border: 1px solid var(--line);
      border-radius: 5px;
      cursor: pointer;
    }

    .hamburger span {
      width: 100%;
      height: 2px;
      display: block;
      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: 80;
      visibility: hidden;
      opacity: 0;
      background: rgba(8, 15, 30, .58);
      transition: opacity .25s ease, visibility .25s;
    }

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

    .mobile-drawer {
      position: fixed;
      top: 0;
      right: 0;
      bottom: 0;
      z-index: 90;
      width: min(390px, 90vw);
      overflow-y: auto;
      background: var(--surface);
      box-shadow: -16px 0 36px rgba(0, 0, 0, .18);
      transform: translateX(105%);
      transition: transform .25s ease;
    }

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

    .drawer-head {
      min-height: 70px;
      padding: 14px 18px;
      display: flex;
      align-items: center;
      gap: 12px;
      color: #ffffff;
      background: var(--theme);
    }

    .drawer-head > a {
      padding: 7px 12px;
      border: 1px solid rgba(255, 255, 255, .45);
      border-radius: 4px;
    }

    .drawer-close {
      width: 38px;
      height: 38px;
      margin-left: auto;
      color: #ffffff;
      background: transparent;
      border: 0;
      cursor: pointer;
      font-size: 30px;
      line-height: 1;
    }

    .drawer-menu {
      padding: 12px 18px 32px;
    }

    .drawer-link,
    .drawer-toggle {
      width: 100%;
      min-height: 48px;
      padding: 12px 4px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: transparent;
      border: 0;
      border-bottom: 1px solid var(--line);
      cursor: pointer;
      text-align: left;
      font-weight: 700;
    }

    .drawer-toggle::after {
      content: "+";
      color: var(--theme);
      font-size: 20px;
    }

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

    .drawer-submenu {
      max-height: 0;
      overflow: hidden;
      background: #f8fafc;
      transition: max-height .3s ease;
    }

    .drawer-submenu.open {
      max-height: 620px;
    }

    .drawer-submenu a {
      padding: 10px 14px;
      display: block;
      color: #475467;
      border-bottom: 1px solid #edf0f4;
      font-size: 14px;
    }

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

    .video-detail-main {
      min-width: 0;
    }

    .video-detail-main .video-breadcrumb {
      padding: 18px 0;
      color: var(--muted);
      font-size: 14px;
    }

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

    .video-detail-main .video-breadcrumb span {
      margin: 0 8px;
      color: #98a2b3;
    }

    .video-detail-main .video-stage {
      color: #ffffff;
      background: #090d16;
      border-top: 3px solid var(--accent);
    }

    .video-detail-main .stage-inner {
      padding: 34px 0 40px;
    }

    .video-detail-main .video-heading {
      max-width: 930px;
      margin-bottom: 24px;
    }

    .video-detail-main .video-label {
      margin-bottom: 10px;
      display: inline-flex;
      align-items: center;
      gap: 7px;
      color: #ff9dca;
      font-size: 13px;
      font-weight: 700;
    }

    .video-detail-main .video-label::before {
      content: "";
      width: 8px;
      height: 8px;
      background: var(--accent);
      border-radius: 50%;
      box-shadow: 0 0 0 5px rgba(212, 20, 109, .16);
    }

    .video-detail-main h1 {
      margin: 0;
      overflow-wrap: anywhere;
      font-size: clamp(28px, 4vw, 48px);
      line-height: 1.25;
      letter-spacing: 0;
    }

    .video-detail-main .video-meta {
      margin-top: 15px;
      display: flex;
      flex-wrap: wrap;
      gap: 9px 22px;
      color: #b7c0d0;
      font-size: 14px;
    }

    .video-detail-main .video-meta span {
      display: inline-flex;
      align-items: center;
      gap: 7px;
    }

    .video-detail-main .video-meta span::before {
      content: "";
      width: 5px;
      height: 5px;
      background: #667085;
      border-radius: 50%;
    }

    .video-detail-main .player-shell {
      position: relative;
      width: 100%;
      overflow: hidden;
      aspect-ratio: 16 / 9;
      background: #000000;
      border: 1px solid #273147;
      border-radius: 7px;
      box-shadow: 0 20px 48px rgba(0, 0, 0, .32);
    }

    .video-detail-main .player-shell iframe,
    .video-detail-main .player-shell video,
    .video-detail-main .player-shell embed,
    .video-detail-main .player-shell object {
      width: 100% !important;
      height: 100% !important;
      display: block;
      border: 0;
    }

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

    .video-detail-main .video-workspace {
      padding: 38px 0 70px;
      display: grid;
      grid-template-columns: minmax(0, 1fr) 330px;
      align-items: start;
      gap: 28px;
    }

    .video-detail-main .video-primary {
      min-width: 0;
    }

    .video-detail-main .content-section {
      min-width: 0;
      margin-bottom: 24px;
      padding: 28px;
      background: var(--surface);
      border: 1px solid var(--line);
      border-radius: 7px;
      box-shadow: 0 7px 22px rgba(16, 24, 40, .05);
    }

    .video-detail-main .section-title {
      margin: 0 0 18px;
      padding-left: 13px;
      color: var(--theme-dark);
      border-left: 4px solid var(--accent);
      font-size: 21px;
      line-height: 1.35;
    }

    .video-detail-main .video-summary {
      margin: 0;
      color: #475467;
      font-size: 16px;
      line-height: 1.9;
      overflow-wrap: anywhere;
    }

    .video-detail-main .video-tags {
      margin-top: 20px;
      padding-top: 18px;
      color: var(--muted);
      border-top: 1px solid var(--line);
      font-size: 14px;
      overflow-wrap: anywhere;
    }

    .video-detail-main .video-tags strong {
      margin-right: 8px;
      color: var(--ink);
    }

    .video-detail-main .video-content {
      min-width: 0;
      max-width: 100%;
      overflow-x: auto;
      color: #344054;
      line-height: 1.9;
      overflow-wrap: anywhere;
    }

    .video-detail-main .video-content > :first-child {
      margin-top: 0;
    }

    .video-detail-main .video-content > :last-child {
      margin-bottom: 0;
    }

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

    .video-detail-main .video-content img {
      height: auto;
      margin: 20px auto;
      border-radius: 6px;
    }

    .video-detail-main .video-content iframe {
      width: 100%;
      aspect-ratio: 16 / 9;
      border: 0;
    }

    .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);
      text-align: left;
    }

    .video-detail-main .video-content a {
      color: var(--theme);
      text-decoration: underline;
    }

    .video-detail-main .video-sidebar {
      position: sticky;
      top: 18px;
      min-width: 0;
    }

    .video-detail-main .sidebar-panel {
      margin-bottom: 20px;
      padding: 22px;
      background: var(--surface);
      border: 1px solid var(--line);
      border-radius: 7px;
      box-shadow: 0 7px 22px rgba(16, 24, 40, .05);
    }

    .video-detail-main .sidebar-panel h2 {
      margin: 0 0 16px;
      color: var(--theme-dark);
      font-size: 18px;
    }

    .video-detail-main .video-facts {
      margin: 0;
    }

    .video-detail-main .video-facts div {
      padding: 11px 0;
      display: flex;
      justify-content: space-between;
      gap: 16px;
      border-bottom: 1px solid var(--line);
    }

    .video-detail-main .video-facts div:last-child {
      border-bottom: 0;
    }

    .video-detail-main .video-facts dt {
      color: var(--muted);
    }

    .video-detail-main .video-facts dd {
      margin: 0;
      color: var(--ink);
      text-align: right;
      overflow-wrap: anywhere;
    }

    .video-detail-main .notice {
      color: #475467;
      font-size: 14px;
    }

    .video-detail-main .notice strong {
      display: block;
      margin-bottom: 7px;
      color: var(--ink);
      font-size: 15px;
    }

    .video-detail-main .related-section {
      padding: 62px 0 74px;
      background: #eef1f5;
      border-top: 1px solid var(--line);
    }

    .video-detail-main .related-head {
      margin-bottom: 23px;
      display: flex;
      align-items: end;
      justify-content: space-between;
      gap: 20px;
    }

    .video-detail-main .related-head h2 {
      margin: 0;
      color: var(--theme-dark);
      font-size: 28px;
    }

    .video-detail-main .related-head a {
      color: var(--theme);
      font-weight: 700;
    }

    .video-detail-main .related-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 18px;
    }

    .video-detail-main .related-card {
      min-width: 0;
      overflow: hidden;
      background: var(--surface);
      border: 1px solid var(--line);
      border-radius: 7px;
      box-shadow: 0 7px 22px rgba(16, 24, 40, .06);
      transition: transform .2s ease, box-shadow .2s ease;
    }

    .video-detail-main .related-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow);
    }

    .video-detail-main .related-cover {
      position: relative;
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #dfe5ee;
    }

    .video-detail-main .related-cover img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform .3s ease;
    }

    .video-detail-main .related-card:hover .related-cover img {
      transform: scale(1.04);
    }

    .video-detail-main .duration {
      position: absolute;
      right: 9px;
      bottom: 9px;
      padding: 3px 7px;
      color: #ffffff;
      background: rgba(8, 12, 20, .82);
      border-radius: 3px;
      font-size: 12px;
    }

    .video-detail-main .play-mark {
      position: absolute;
      top: 50%;
      left: 50%;
      width: 44px;
      height: 44px;
      display: grid;
      place-items: center;
      color: #ffffff;
      background: rgba(212, 20, 109, .92);
      border-radius: 50%;
      transform: translate(-50%, -50%);
    }

    .video-detail-main .play-mark::before {
      content: "";
      margin-left: 3px;
      border-top: 7px solid transparent;
      border-bottom: 7px solid transparent;
      border-left: 11px solid #ffffff;
    }

    .video-detail-main .related-body {
      padding: 17px;
    }

    .video-detail-main .related-body h3 {
      min-height: 48px;
      margin: 0 0 8px;
      display: -webkit-box;
      overflow: hidden;
      color: #1d2939;
      font-size: 16px;
      line-height: 24px;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .video-detail-main .related-body p {
      height: 42px;
      margin: 0;
      display: -webkit-box;
      overflow: hidden;
      color: var(--muted);
      font-size: 13px;
      line-height: 21px;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .footer {
      color: #cbd5e1;
      background: #09152b;
    }

    .footer-main {
      padding: 58px 0 42px;
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1.1fr;
      gap: 40px;
    }

    .footer .logo {
      color: #ffffff;
    }

    .footer-brand p {
      max-width: 420px;
      margin: 18px 0;
      color: #9eacc2;
      font-size: 14px;
    }

    .footer-social {
      overflow-wrap: anywhere;
    }

    .footer-column h3 {
      margin: 7px 0 17px;
      color: #ffffff;
      font-size: 16px;
    }

    .footer-links {
      display: grid;
      gap: 10px;
    }

    .footer-links a {
      color: #aebbd0;
      font-size: 14px;
    }

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

    .footer-contact {
      display: grid;
      gap: 14px;
      color: #aebbd0;
      font-size: 14px;
    }

    .footer-contact span {
      color: #74839b;
      font-size: 12px;
    }

    .footer-bottom {
      min-height: 68px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 18px;
      color: #8492a8;
      border-top: 1px solid rgba(255, 255, 255, .1);
      font-size: 13px;
    }

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

      .hamburger {
        display: flex;
      }

      .header-inner {
        justify-content: space-between;
      }

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

      .video-detail-main .video-workspace {
        grid-template-columns: minmax(0, 1fr) 290px;
      }
    }

    @media (max-width: 860px) {
      .video-detail-main .video-workspace {
        grid-template-columns: 1fr;
      }

      .video-detail-main .video-sidebar {
        position: static;
      }

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

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

    @media (max-width: 620px) {
      .container {
        width: min(100% - 28px, var(--container));
      }

      .topbar-inner {
        padding: 7px 0;
        align-items: flex-start;
        flex-direction: column;
        gap: 3px;
      }

      .topbar-contact {
        width: 100%;
        align-items: flex-start;
        flex-direction: column;
        gap: 2px;
      }

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

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

      .logo span {
        max-width: 128px;
        font-size: 16px;
      }

      .header-btns {
        gap: 7px;
      }

      .member-entry {
        display: none;
      }

      .account-entry {
        min-height: 36px;
        padding: 7px 11px;
        font-size: 14px;
      }

      .hamburger {
        width: 38px;
        height: 38px;
      }

      .video-detail-main .video-breadcrumb {
        padding: 13px 0;
      }

      .video-detail-main .stage-inner {
        padding: 25px 0 28px;
      }

      .video-detail-main h1 {
        font-size: 28px;
      }

      .video-detail-main .player-shell {
        border-radius: 4px;
      }

      .video-detail-main .video-workspace {
        padding: 24px 0 45px;
        gap: 18px;
      }

      .video-detail-main .content-section,
      .video-detail-main .sidebar-panel {
        padding: 20px;
      }

      .video-detail-main .related-section {
        padding: 42px 0 50px;
      }

      .video-detail-main .related-head {
        align-items: flex-start;
        flex-direction: column;
        gap: 8px;
      }

      .video-detail-main .related-head h2 {
        font-size: 24px;
      }

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

      .footer-main {
        padding: 42px 0 32px;
        grid-template-columns: 1fr;
        gap: 28px;
      }

      .footer-bottom {
        padding: 18px 0;
        align-items: flex-start;
        flex-direction: column;
        justify-content: center;
        gap: 5px;
      }
    }