:root {
      --page-bg: #ffffff;
      --text: #0f1014;
      --muted: #5c606a;
      --soft: #82889a;
      --line: rgba(17, 18, 24, 0.08);
      --line-strong: rgba(17, 18, 24, 0.14);
      --panel: #f7f8fb;
      --panel-blue: #edf7ff;
      --btn-dark: #262629;
      --btn-dark-hover: #3a3a3d;
      --interaction-blue: #4E63EB;
      --hover-soft-bg: #f6f7fb;
      --card-hover-border: rgba(78, 99, 235, 0.18);
      --card-hover-shadow: 0 12px 22px rgba(28, 38, 66, 0.14);
      --shadow-soft: 0 18px 40px rgba(18, 30, 62, 0.08);
      --shadow-tag: 0 10px 18px rgba(28, 38, 66, 0.08);
      --stage-width: 1400px;
      --nav-width: 1880px;
      --hero-height: 560px;
      --course-height: 206px;
    }

    * {
      box-sizing: border-box;
    }

    html,
    body {
      margin: 0;
      min-height: 100%;
      background: var(--page-bg);
      color: var(--text);
      font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
    }

    html {
      overflow-x: hidden;
      overflow-y: auto;
      scrollbar-gutter: stable;
    }

    body {
      overflow-x: hidden;
      overflow-y: visible;
    }

    .page {
      overflow-x: clip;
    }

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

    a[href] {
      cursor: pointer;
    }

    button {
      border: 0;
      background: none;
      font: inherit;
      color: inherit;
      cursor: pointer;
    }

    .page {
      min-height: 100vh;
      background: #ffffff;
    }

    .topbar {
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      z-index: 50;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
      width: auto;
      margin: 0;
      padding: 12px 20px;
      border-bottom: 1px solid transparent;
      background: transparent;
      box-shadow: none;
      -webkit-backdrop-filter: blur(0) saturate(100%);
      backdrop-filter: blur(0) saturate(100%);
      transition:
        background-color 220ms ease,
        border-color 220ms ease,
        box-shadow 260ms ease,
        backdrop-filter 260ms ease,
        -webkit-backdrop-filter 260ms ease;
    }

    .topbar.is-scrolled {
      border-bottom-color: rgba(227, 233, 241, 0.66);
      background: rgba(255, 255, 255, 0.72);
      box-shadow: 0 10px 30px rgba(17, 24, 39, 0.04);
      -webkit-backdrop-filter: blur(18px) saturate(160%);
      backdrop-filter: blur(18px) saturate(160%);
    }

    .brand {
      display: inline-flex;
      align-items: center;
      min-width: 163px;
    }

    .brand-image {
      display: block;
      width: 163px;
      height: 26px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 80px;
      flex: 1 1 auto;
      min-width: 0;
      padding: 0 12px;
    }

    .nav-links a {
      font-size: 14px;
      font-weight: 400;
      color: #555555;
      transition: color 160ms ease;
    }

    .nav-links a:hover {
      color: var(--interaction-blue);
    }

    .topbar-actions {
      display: inline-flex;
      align-items: center;
      gap: 26px;
      min-width: auto;
      justify-content: flex-end;
      color: rgba(0, 0, 0, 0.9);
      font-size: 14px;
      font-weight: 400;
    }

    .topbar-search {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      min-width: 72px;
      height: 32px;
      padding: 0 10px;
      border: 0;
      border-radius: 18px;
      background: transparent;
      box-shadow: none;
      color: rgba(0, 0, 0, 0.9);
      font-size: 14px;
      line-height: 20px;
      white-space: nowrap;
      transition: background-color 180ms ease, opacity 180ms ease, color 180ms ease;
    }

    .topbar-search.is-active {
      background: #f1f2f5;
      opacity: 1;
    }

    .topbar-search.is-active:hover {
      opacity: 1;
    }

    .search-icon-image {
      display: inline-block;
      width: 18px;
      height: 18px;
      flex: 0 0 auto;
    }

    .topbar-search-text {
      overflow: visible;
      text-overflow: clip;
    }

    .register-link {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 76px;
      height: 40px;
      padding: 0;
      border-radius: 22px;
      color: #ffffff;
      background: linear-gradient(237deg, #d730ff 0%, #ff3494 29.42%, #ff3856 60.04%, #ff6956 80.94%, #ff7a00 100%);
      box-shadow: 0 12px 20px rgba(255, 93, 126, 0.22);
      font-weight: 500;
    }

    .search-panel {
      position: fixed;
      inset: 0;
      z-index: 80;
      pointer-events: none;
      opacity: 0;
      padding-top: 72px;
      background: rgba(0, 0, 0, 0.06);
      transition: opacity 180ms ease;
    }

    .search-panel.is-open {
      pointer-events: auto;
      opacity: 1;
    }

    .search-panel-card {
      width: min(920px, calc(100vw - 48px));
      min-height: 344px;
      margin: 0 auto;
      padding: 28px 32px 30px;
      border: 1px solid rgba(227, 233, 241, 0.8);
      border-radius: 18px;
      background: rgba(255, 255, 255, 0.96);
      box-shadow: 0 18px 48px rgba(17, 24, 39, 0.12);
      transform: translateY(-8px);
      transition: transform 220ms cubic-bezier(0.22, 1, 0.36, 1);
      -webkit-backdrop-filter: blur(18px) saturate(140%);
      backdrop-filter: blur(18px) saturate(140%);
    }

    .search-panel.is-open .search-panel-card {
      transform: translateY(0);
    }

    .search-panel-head {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 24px;
      padding: 0 0 16px;
      border-bottom: 1px solid #e9ebf0;
    }

    .search-panel-query-shell {
      flex: 1 1 auto;
      min-width: 0;
    }

    .search-panel-input {
      display: block;
      width: 100%;
      min-height: 36px;
      padding: 0 0 0 12px;
      border: 0;
      outline: none;
      background: transparent;
      color: #222222;
      font-size: 24px;
      line-height: 1.2;
      font-weight: 400;
      letter-spacing: 0.01em;
    }

    .search-panel-input::placeholder {
      color: #c6c6c6;
      opacity: 1;
    }

    .search-panel-input:focus-visible {
      outline: none;
    }

    .search-panel-icon {
      width: 18px;
      height: 18px;
      margin-right: 12px;
      opacity: 0.45;
    }

    .search-panel-content {
      display: grid;
      gap: 20px;
      width: 100%;
      padding: 22px 0 0;
    }

    .search-panel-section {
      display: grid;
      gap: 6px;
    }

    .search-panel-title {
      display: inline-flex;
      align-items: center;
      gap: 2px;
      margin: 0 0 4px;
      padding-left: 12px;
      color: #777777;
      font-size: 14px;
      line-height: 20px;
      font-weight: 400;
    }

    .search-panel-title-icon {
      display: block;
      width: 14px;
      height: 14px;
      flex: 0 0 14px;
    }

    .search-panel-list {
      display: grid;
      gap: 0;
      margin: 0;
      padding: 0;
      list-style: none;
    }

    .search-panel-item {
      width: 100%;
      display: inline-flex;
      align-items: center;
      min-height: 34px;
      padding: 4px 12px;
      border-radius: 8px;
      background: transparent;
      color: #222222;
      font-size: 14px;
      line-height: 20px;
      font-weight: 400;
      cursor: pointer;
      transition: background-color 160ms ease;
    }

    .search-panel-item:hover {
      background: #eceff3;
    }

    .search-hot-badge {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      height: 16.2px;
      margin-left: 6px;
      padding: 0 4px;
      border-radius: 4px;
      background: #ff3c72;
      color: #ffffff;
      font-size: 9px;
      line-height: 16.2px;
      font-weight: 700;
      transform: scale(0.9);
      transform-origin: left center;
      vertical-align: middle;
    }

    .hero {
      position: relative;
      overflow: visible;
      background: #ffffff;
      height: var(--hero-height);
    }

    .hero-bg-canvas {
      position: absolute;
      left: 0;
      top: 0;
      width: 100%;
      height: 765px;
      pointer-events: none;
      overflow: hidden;
      z-index: 0;
    }

    .hero-stage {
      position: relative;
      width: min(var(--stage-width), calc(100% - 40px));
      height: var(--hero-height);
      margin: 0 auto;
      isolation: isolate;
      z-index: 2;
    }

    .hero-stage::after {
      content: "";
      position: absolute;
      left: 20px;
      top: 286px;
      width: 1px;
      height: calc(var(--hero-height) + var(--course-height) - 286px);
      background: rgba(0, 0, 0, 0.4);
      z-index: 6;
      pointer-events: none;
    }

    .hero-ribbon {
      position: absolute;
      top: 0;
      left: calc(50% - 989px);
      width: 2459px;
      height: 765px;
      max-width: none;
      pointer-events: none;
      user-select: none;
      z-index: 0;
      transform: none;
    }

    .hero-liquid-ribbon {
      position: absolute;
      top: 0;
      left: calc(50% - 989px);
      width: 2459px;
      height: 765px;
      max-width: none;
      pointer-events: none;
      user-select: none;
      z-index: 1;
      opacity: 1;
    }

    .hero-grid {
      position: relative;
      display: block;
      height: var(--hero-height);
      padding-top: 108px;
    }

    .hero-copy {
      position: relative;
      padding: 0;
      width: 534px;
      z-index: 3;
    }

    .eyebrow {
      margin: 0;
      font-size: 16px;
      font-weight: 400;
      letter-spacing: 0;
      color: #000000;
    }

    .hero-title {
      margin: 4px 0 0;
      font-size: 70px;
      line-height: 98px;
      letter-spacing: 0.55px;
      font-weight: 600;
      color: #000000;
    }

    .hero-highlight {
      display: inline-flex;
      align-items: center;
      gap: 14px;
      margin-top: 4px;
    }

    .hero-squares {
      position: relative;
      width: 28px;
      height: 28px;
      flex: 0 0 auto;
    }

    .hero-squares span {
      position: absolute;
      width: 14px;
      height: 14px;
      border-radius: 1px;
    }

    .hero-squares span:nth-child(1) {
      left: 0;
      top: 0;
      background: #7183f8;
    }

    .hero-squares span:nth-child(2) {
      left: 14px;
      top: 14px;
      background: #ef835f;
    }

    .hero-subtitle {
      margin: 0;
      font-size: 32px;
      line-height: 45px;
      letter-spacing: 0;
      font-weight: 400;
      color: #000000;
      white-space: nowrap;
    }

    .hero-desc {
      max-width: 494px;
      margin: 8px 0 0 40px;
      font-size: 14px;
      line-height: 20px;
      color: #000000;
    }

    .hero-actions {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 24px;
      flex-wrap: wrap;
      margin-left: 40px;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 14px;
      height: 42px;
      padding: 0 23px;
      border-radius: 999px;
      border: 1px solid rgba(38, 38, 41, 0.28);
      font-size: 14px;
      font-weight: 600;
      transition:
        transform 160ms ease,
        background-color 160ms ease,
        border-color 160ms ease,
        color 160ms ease;
    }

    .btn:hover {
      transform: none;
    }

    .btn-primary {
      width: 216px;
      padding-left: 24px;
      padding-right: 24px;
      justify-content: space-between;
      background: var(--btn-dark);
      border-color: transparent;
      color: #ffffff;
      box-shadow: none;
    }

    .btn-primary:hover {
      background: var(--btn-dark-hover);
    }

    .btn-arrow {
      position: relative;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 18px;
      height: 18px;
      flex: 0 0 auto;
    }

    .btn-arrow::before,
    .btn-arrow::after {
      display: none;
    }

    .btn-arrow img {
      display: block;
      width: 18px;
      height: 18px;
    }

    .btn-secondary {
      background: #ffffff;
      color: #262629;
      font-weight: 400;
    }

    .hero-visual-layer {
      position: relative;
      position: absolute;
      left: calc(50% - 252px);
      top: 72px;
      width: 876px;
      height: 615px;
      z-index: 2;
      pointer-events: none;
    }

    .hero-visual-motion {
      position: absolute;
      inset: 0;
    }

    .hero-overlay {
      position: absolute;
      inset: 0;
      width: 876px;
      height: 615px;
      display: block;
      z-index: 2;
    }

    .course-strip {
      position: relative;
      background: rgba(242, 243, 244, 0.5);
      -webkit-backdrop-filter: blur(38px);
      backdrop-filter: blur(38px);
      border-top: 1px solid rgba(255, 255, 255, 0.72);
      border-bottom: 1px solid rgba(11, 19, 34, 0.04);
      height: var(--course-height);
      margin-top: 0;
      z-index: 5;
    }

    .course-strip::before {
      content: "";
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, rgba(255, 255, 255, 0.2), rgba(255, 255, 255, 0.04));
      pointer-events: none;
    }

    .course-grid {
      position: relative;
      z-index: 1;
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      width: min(var(--stage-width), calc(100% - 80px));
      height: 100%;
      margin: 0 auto;
    }

    .course-card {
      position: relative;
      min-height: var(--course-height);
      padding: 38px 24px 24px;
      background: rgba(255, 255, 255, 0);
      -webkit-backdrop-filter: blur(0) saturate(100%);
      backdrop-filter: blur(0) saturate(100%);
      transition:
        background-color 180ms ease,
        background 180ms ease,
        transform 180ms ease,
        backdrop-filter 220ms ease,
        -webkit-backdrop-filter 220ms ease;
    }

    .course-card + .course-card::before {
      content: "";
      position: absolute;
      left: 0;
      top: 50%;
      width: 1px;
      height: 126px;
      transform: translateY(-50%);
      background: rgba(17, 18, 24, 0.08);
    }

    .course-card:hover {
      background: rgba(240, 244, 247, 0.66);
      -webkit-backdrop-filter: blur(14px) saturate(122%);
      backdrop-filter: blur(14px) saturate(122%);
      transform: none;
      box-shadow: none;
      z-index: auto;
    }

    .course-card-inner {
      max-width: 292px;
      margin: 0 auto;
    }

    .course-icon-shell {
      position: relative;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 36px;
      height: 36px;
      border-radius: 8px;
      background: rgba(255, 255, 255, 0.7);
    }

    .course-icon {
      width: 36px;
      height: 36px;
      display: block;
    }

    .course-icon-svg {
      display: block;
      width: 36px;
      height: 36px;
      overflow: visible;
    }

    .course-card:nth-child(n+2) .course-icon-svg {
      display: none;
    }

    .course-card:nth-child(n+2) .course-icon-shell::before {
      content: "";
      width: 36px;
      height: 36px;
      display: block;
      background-position: center;
      background-repeat: no-repeat;
      background-size: contain;
      transition:
        transform 260ms cubic-bezier(0.22, 1, 0.36, 1),
        filter 260ms ease;
    }

    .course-card:nth-child(3) .course-icon-shell::after {
      content: "";
      position: absolute;
      inset: 0;
      display: block;
      background: url("assets/custom/docs-wave.svg") center / contain no-repeat;
      pointer-events: none;
    }

    .course-card:nth-child(2) .course-icon-shell::before {
      background-image: url("assets/custom/community-activity.svg");
    }

    .course-card:nth-child(3) .course-icon-shell::before {
      background-image: url("assets/custom/docs.svg");
    }

    .course-card:nth-child(4) .course-icon-shell::before {
      background-image: url("assets/custom/community-co-build.svg");
    }

    .course-card:nth-child(n+2):hover .course-icon-shell::before {
      filter: drop-shadow(0 0 8px rgba(96, 115, 240, 0.24));
    }

    .course-card:nth-child(2):hover .course-icon-shell::before {
      animation: courseIconFloat 620ms cubic-bezier(0.22, 1, 0.36, 1) both;
    }