:root {
      --theme: #0B3D91;
      --ink: #1e293b;
      --muted: #64748b;
      --line: #dbe3ec;
      --mist: #f4f7f9;
      --white: #ffffff;
      --dark: #102335;
      --accent: #7e9d84;
      --shadow: 0 18px 45px rgba(23, 45, 63, .12);
    }

    * {
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      margin: 0;
      color: var(--ink);
      background: var(--mist);
      font-family: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", sans-serif;
      line-height: 1.7;
    }

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

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

    button {
      font: inherit;
    }

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

    .topbar {
      color: #e8f0f4;
      background: #182d3c;
      font-size: 13px;
    }

    .topbar .container {
      min-height: 38px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
    }

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

    .topbar a {
      color: #dce9ed;
    }

    .header {
      position: relative;
      z-index: 20;
      background: var(--white);
      border-bottom: 1px solid var(--line);
    }

    .header-inner {
      min-height: 78px;
      display: flex;
      align-items: center;
      gap: 30px;
    }

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

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

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

    .nav-list {
      height: 100%;
      display: flex;
      align-items: stretch;
      justify-content: center;
      gap: 4px;
      list-style: none;
      padding: 0;
      margin: 0;
    }

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

    .nav-link {
      display: inline-flex;
      align-items: center;
      min-height: 78px;
      padding: 0 14px;
      color: #334155;
      font-size: 15px;
      font-weight: 700;
      white-space: nowrap;
    }

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

    .has-arrow::after {
      content: "";
      width: 6px;
      height: 6px;
      margin: 2px 0 0 8px;
      border-right: 1px solid currentColor;
      border-bottom: 1px solid currentColor;
      transform: rotate(45deg);
    }

    .dropdown-panel,
    .mega-menu {
      position: absolute;
      top: calc(100% - 1px);
      left: 50%;
      z-index: 30;
      width: 340px;
      padding: 18px;
      visibility: hidden;
      opacity: 0;
      transform: translate(-50%, 8px);
      background: var(--white);
      border: 1px solid var(--line);
      box-shadow: var(--shadow);
      transition: opacity .2s ease, transform .2s ease, visibility .2s ease;
    }

    .mega-menu {
      width: min(680px, 80vw);
    }

    .dropdown-panel::before,
    .mega-menu::before {
      content: "";
      position: absolute;
      top: -10px;
      left: 0;
      right: 0;
      height: 10px;
    }

    .nav-item:hover .dropdown-panel,
    .nav-item:focus-within .dropdown-panel,
    .nav-item:hover .mega-menu,
    .nav-item:focus-within .mega-menu {
      visibility: visible;
      opacity: 1;
      transform: translate(-50%, 0);
    }

    .dropdown-panel > a:not(.mega-footer) {
      display: block;
      padding: 9px 10px;
      border-bottom: 1px solid #edf1f4;
      font-size: 14px;
    }

    .dropdown-panel > a:hover,
    .mega-card:hover {
      color: var(--theme);
      background: #f2f6fb;
    }

    .mega-heading {
      display: flex;
      justify-content: space-between;
      gap: 16px;
      padding: 0 2px 12px;
      color: var(--dark);
      font-size: 13px;
      font-weight: 800;
      border-bottom: 1px solid var(--line);
    }

    .mega-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 8px;
      padding: 12px 0;
      max-height: 390px;
      overflow: auto;
    }

    .mega-card {
      min-height: 82px;
      display: flex;
      flex-direction: column;
      justify-content: center;
      gap: 3px;
      padding: 10px;
      border: 1px solid #e5ebf0;
      background: #fbfcfd;
      transition: background .2s ease, color .2s ease;
    }

    .mega-card img {
      width: 25px;
      height: 25px;
      object-fit: contain;
      margin-bottom: 2px;
    }

    .mega-card strong {
      overflow: hidden;
      text-overflow: ellipsis;
      white-space: nowrap;
      font-size: 13px;
    }

    .mega-card small {
      color: var(--muted);
      font-size: 11px;
      line-height: 1.45;
    }

    .mega-footer {
      display: block;
      padding-top: 11px;
      color: var(--theme);
      font-size: 13px;
      font-weight: 800;
      border-top: 1px solid var(--line);
    }

    .header-btns {
      display: flex;
      align-items: center;
      gap: 10px;
      white-space: nowrap;
    }

    .member-link,
    .account-link {
      padding: 8px 13px;
      font-size: 13px;
      font-weight: 800;
    }

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

    .account-link {
      color: var(--white);
      background: var(--theme);
      border: 1px solid var(--theme);
    }

    .hamburger {
      display: none;
      width: 42px;
      height: 42px;
      padding: 9px;
      border: 1px solid var(--line);
      background: var(--white);
      cursor: pointer;
    }

    .hamburger span {
      display: block;
      height: 2px;
      margin: 5px 0;
      background: var(--dark);
      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: 40;
      display: none;
      background: rgba(11, 30, 43, .5);
    }

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

    .mobile-drawer {
      position: fixed;
      top: 0;
      right: 0;
      z-index: 50;
      width: min(390px, 88vw);
      height: 100vh;
      padding: 20px;
      overflow-y: auto;
      background: var(--white);
      box-shadow: -12px 0 35px rgba(15, 35, 50, .18);
      transform: translateX(105%);
      transition: transform .25s ease;
    }

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

    .drawer-head {
      display: flex;
      align-items: center;
      gap: 12px;
      padding-bottom: 18px;
      border-bottom: 1px solid var(--line);
      font-weight: 800;
    }

    .drawer-head span {
      flex: 1;
    }

    .drawer-head a {
      color: var(--theme);
      font-size: 14px;
    }

    .drawer-close {
      width: 34px;
      height: 34px;
      border: 1px solid var(--line);
      color: var(--dark);
      background: var(--white);
      cursor: pointer;
      font-size: 23px;
      line-height: 1;
    }

    .drawer-menu {
      padding-top: 10px;
    }

    .drawer-link,
    .drawer-toggle {
      width: 100%;
      display: block;
      padding: 13px 4px;
      color: var(--dark);
      text-align: left;
      background: transparent;
      border: 0;
      border-bottom: 1px solid #edf1f4;
      cursor: pointer;
      font-weight: 700;
    }

    .drawer-toggle::after {
      content: "+";
      float: right;
      color: var(--muted);
      font-size: 18px;
      font-weight: 400;
    }

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

    .drawer-submenu {
      display: none;
      padding: 5px 0 8px 14px;
      border-bottom: 1px solid #edf1f4;
    }

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

    .drawer-submenu a {
      display: block;
      padding: 8px 4px;
      color: var(--muted);
      font-size: 14px;
    }

    .video-detail-main {
      padding: 54px 0 88px;
    }

    .video-detail-main .breadcrumb {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-bottom: 20px;
      color: var(--muted);
      font-size: 13px;
    }

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

    .video-header {
      max-width: 860px;
      margin: 0 auto 28px;
      text-align: center;
    }

    .video-kicker {
      display: inline-flex;
      align-items: center;
      min-height: 28px;
      padding: 3px 11px;
      color: var(--theme);
      background: #e7eef8;
      border: 1px solid #c9d8eb;
      font-size: 12px;
      font-weight: 800;
      letter-spacing: .04em;
    }

    .video-header h1 {
      margin: 15px 0 10px;
      color: var(--dark);
      font-size: clamp(28px, 4vw, 48px);
      line-height: 1.2;
    }

    .video-header p {
      max-width: 720px;
      margin: 0 auto;
      color: var(--muted);
    }

    .video-meta {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 8px 20px;
      margin-top: 18px;
      color: var(--muted);
      font-size: 13px;
    }

    .video-player-shell {
      max-width: 1000px;
      margin: 0 auto;
      background: #101b24;
      box-shadow: var(--shadow);
    }

    .video-player {
      position: relative;
      min-height: 520px;
      display: grid;
      place-items: center;
      overflow: hidden;
      background:
        linear-gradient(145deg, rgba(11, 61, 145, .34), rgba(17, 42, 53, .86)),
        url("{视频封面}") center / cover no-repeat;
    }

    .video-player::after {
      content: "";
      position: absolute;
      inset: 0;
      background: linear-gradient(0deg, rgba(8, 19, 27, .72), transparent 58%);
      pointer-events: none;
    }

    .video-player-content {
      position: relative;
      z-index: 1;
      width: min(660px, calc(100% - 40px));
      padding: 28px;
      color: var(--white);
      text-align: center;
      background: rgba(13, 31, 42, .68);
      border: 1px solid rgba(255, 255, 255, .2);
    }

    .video-player-content h2 {
      margin: 0 0 8px;
      font-size: 22px;
    }

    .video-player-content p {
      margin: 0 0 20px;
      color: #dbe8ed;
      font-size: 14px;
    }

    .player-action {
      display: inline-flex;
      align-items: center;
      gap: 10px;
      padding: 12px 20px;
      color: var(--white);
      background: var(--theme);
      border: 1px solid #7195c8;
      font-weight: 800;
    }

    .player-action::before {
      content: "▶";
      font-size: 12px;
    }

    .video-player-native {
      width: 100%;
      max-height: 600px;
      background: #091118;
    }

    .video-player-native:empty {
      display: none;
    }

    .video-info-grid {
      display: grid;
      grid-template-columns: minmax(0, 1fr) 300px;
      gap: 28px;
      max-width: 1000px;
      margin: 30px auto 0;
    }

    .video-content,
    .video-side-panel {
      background: var(--white);
      border: 1px solid var(--line);
      box-shadow: 0 8px 24px rgba(34, 55, 70, .05);
    }

    .video-content {
      min-width: 0;
      padding: 30px;
    }

    .video-content h2,
    .video-side-panel h2 {
      margin: 0 0 18px;
      color: var(--dark);
      font-size: 20px;
    }

    .video-body {
      min-width: 0;
      max-width: 100%;
      overflow-x: auto;
      color: #475569;
    }

    .video-body img,
    .video-body video,
    .video-body iframe,
    .video-body table {
      max-width: 100%;
    }

    .video-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 26px;
      padding-top: 20px;
      border-top: 1px solid var(--line);
    }

    .video-tags span {
      padding: 4px 10px;
      color: var(--theme);
      background: #eef3f9;
      font-size: 12px;
    }

    .video-side-panel {
      align-self: start;
      padding: 24px;
    }

    .video-side-panel dl {
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 10px 14px;
      margin: 0;
      font-size: 14px;
    }

    .video-side-panel dt {
      color: var(--muted);
    }

    .video-side-panel dd {
      margin: 0;
      color: var(--dark);
      font-weight: 700;
      text-align: right;
    }

    .related-videos {
      padding: 68px 0 0;
    }

    .section-heading {
      display: flex;
      align-items: end;
      justify-content: space-between;
      gap: 18px;
      margin-bottom: 18px;
    }

    .section-heading h2 {
      margin: 0;
      color: var(--dark);
      font-size: 25px;
    }

    .section-heading a {
      color: var(--theme);
      font-size: 14px;
      font-weight: 800;
    }

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

    .related-card {
      overflow: hidden;
      background: var(--white);
      border: 1px solid var(--line);
      transition: transform .2s ease, box-shadow .2s ease;
    }

    .related-card:hover {
      transform: translateY(-3px);
      box-shadow: 0 12px 26px rgba(29, 52, 68, .1);
    }

    .related-cover {
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #dce5e8;
    }

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

    .related-card-body {
      padding: 15px;
    }

    .related-card h3 {
      margin: 0 0 6px;
      color: var(--dark);
      font-size: 16px;
      line-height: 1.45;
    }

    .related-card p {
      display: -webkit-box;
      min-height: 48px;
      margin: 0 0 10px;
      overflow: hidden;
      color: var(--muted);
      font-size: 13px;
      -webkit-box-orient: vertical;
      -webkit-line-clamp: 2;
    }

    .related-card-meta {
      display: flex;
      justify-content: space-between;
      gap: 8px;
      color: var(--muted);
      font-size: 12px;
    }

    .footer {
      padding: 52px 0 22px;
      color: #d6e1e7;
      background: #172c3a;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.3fr 1fr 1fr 1fr;
      gap: 34px;
    }

    .footer h2,
    .footer h3 {
      margin: 0 0 14px;
      color: var(--white);
    }

    .footer h2 {
      font-size: 20px;
    }

    .footer h3 {
      font-size: 14px;
    }

    .footer p {
      max-width: 300px;
      margin: 0;
      color: #b8c9d2;
      font-size: 13px;
    }

    .footer-links {
      display: grid;
      gap: 8px;
      padding: 0;
      margin: 0;
      list-style: none;
      color: #b8c9d2;
      font-size: 13px;
    }

    .footer-links a:hover {
      color: var(--white);
    }

    .footer-bottom {
      display: flex;
      justify-content: space-between;
      gap: 20px;
      margin-top: 38px;
      padding-top: 18px;
      color: #9fb4c0;
      border-top: 1px solid rgba(255, 255, 255, .14);
      font-size: 12px;
    }

    @media (max-width: 980px) {
      .main-nav {
        display: none;
      }

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

      .hamburger {
        display: block;
      }

      .video-info-grid {
        grid-template-columns: 1fr;
      }

      .video-side-panel {
        order: -1;
      }

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

    @media (max-width: 680px) {
      .container {
        width: min(100% - 28px, 1180px);
      }

      .topbar .container {
        min-height: 48px;
        align-items: flex-start;
        flex-direction: column;
        justify-content: center;
        gap: 0;
      }

      .topbar-links {
        gap: 12px;
        font-size: 11px;
      }

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

      .logo {
        font-size: 16px;
      }

      .logo img {
        width: 32px;
        height: 32px;
      }

      .member-link {
        display: none;
      }

      .video-detail-main {
        padding: 32px 0 60px;
      }

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

      .video-player {
        min-height: 330px;
      }

      .video-player-content {
        padding: 20px 15px;
      }

      .video-player-content h2 {
        font-size: 18px;
      }

      .video-content {
        padding: 20px;
      }

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

      .footer-grid {
        grid-template-columns: 1fr;
        gap: 24px;
      }

      .footer-bottom {
        align-items: flex-start;
        flex-direction: column;
        gap: 7px;
      }
    }