/* roulang page: index */
:root {
      --bg-dark: #070B14;
      --bg-deep: #040711;
      --card-bg: rgba(16, 27, 59, 0.65);
      --card-border: rgba(56, 189, 248, 0.16);
      --accent-cyan: #38BDF8;
      --accent-teal: #2DD4BF;
      --text-main: #F8FAFC;
      --text-muted: #94A3B8;
      --text-dim: #64748B;
    }
    body {
      background-color: var(--bg-dark);
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      overflow-x: hidden;
      margin: 0;
    }
    .glass-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
      transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .glass-card:hover {
      border-color: rgba(56, 189, 248, 0.4);
      background: rgba(22, 36, 75, 0.72);
      transform: translateY(-3px);
      box-shadow: 0 14px 34px -4px rgba(56, 189, 248, 0.22);
    }
    .btn-glow {
      background: linear-gradient(135deg, #0284C7 0%, #38BDF8 100%);
      box-shadow: 0 0 16px rgba(56, 189, 248, 0.35);
      transition: all 0.25s ease;
    }
    .btn-glow:hover {
      transform: translateY(-2px);
      box-shadow: 0 0 26px rgba(56, 189, 248, 0.65);
    }
    .btn-ghost {
      border: 1px solid rgba(56, 189, 248, 0.3);
      background: rgba(15, 23, 42, 0.6);
      transition: all 0.25s ease;
    }
    .btn-ghost:hover {
      background: rgba(56, 189, 248, 0.15);
      border-color: #38BDF8;
      transform: translateY(-1px);
    }
    .nav-active-line {
      position: relative;
    }
    .nav-active-line::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 100%;
      height: 2px;
      background: linear-gradient(90deg, #38BDF8, #2DD4BF);
      border-radius: 9999px;
      box-shadow: 0 0 8px #38BDF8;
    }
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease-out;
    }
    .faq-item.active .faq-content {
      max-height: 260px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(180deg);
    }
    .faq-item.active {
      border-color: rgba(56, 189, 248, 0.45);
    }
    .pulse-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background-color: #2DD4BF;
      box-shadow: 0 0 10px #2DD4BF;
      animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
    }
    @keyframes pulse {
      0%, 100% { opacity: 1; transform: scale(1); }
      50% { opacity: 0.5; transform: scale(1.2); }
    }
    .hero-strip {
      background: linear-gradient(180deg, rgba(56, 189, 248, 0.08) 0%, rgba(7, 11, 20, 1) 100%);
      border-bottom: 1px solid rgba(56, 189, 248, 0.12);
    }

/* roulang page: article */
:root {
      --bg-dark: #070B14;
      --bg-deep: #040711;
      --card-bg: rgba(16, 27, 59, 0.65);
      --card-border: rgba(56, 189, 248, 0.16);
      --accent-cyan: #38BDF8;
      --accent-teal: #2DD4BF;
      --text-main: #F8FAFC;
      --text-muted: #94A3B8;
      --text-dim: #64748B;
    }
    body {
      background-color: var(--bg-dark);
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      overflow-x: hidden;
      margin: 0;
    }
    .glass-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
      transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .glass-card:hover {
      border-color: rgba(56, 189, 248, 0.4);
      background: rgba(22, 36, 75, 0.72);
      transform: translateY(-3px);
      box-shadow: 0 14px 34px -4px rgba(56, 189, 248, 0.22);
    }
    .btn-glow {
      background: linear-gradient(135deg, #0284C7 0%, #38BDF8 100%);
      box-shadow: 0 0 16px rgba(56, 189, 248, 0.35);
      transition: all 0.25s ease;
    }
    .btn-glow:hover {
      transform: translateY(-2px);
      box-shadow: 0 0 26px rgba(56, 189, 248, 0.65);
    }
    .btn-ghost {
      border: 1px solid rgba(56, 189, 248, 0.3);
      background: rgba(15, 23, 42, 0.6);
      transition: all 0.25s ease;
    }
    .btn-ghost:hover {
      background: rgba(56, 189, 248, 0.15);
      border-color: #38BDF8;
      transform: translateY(-1px);
    }
    .nav-active-line {
      position: relative;
    }
    .nav-active-line::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 100%;
      height: 2px;
      background: linear-gradient(90deg, #38BDF8, #2DD4BF);
      border-radius: 9999px;
      box-shadow: 0 0 8px #38BDF8;
    }
    .hero-strip {
      background: linear-gradient(180deg, rgba(56, 189, 248, 0.08) 0%, rgba(7, 11, 20, 1) 100%);
      border-bottom: 1px solid rgba(56, 189, 248, 0.12);
    }
    .article-content {
      line-height: 1.85;
      font-size: 16px;
      color: #CBD5E1;
    }
    .article-content h2 {
      font-size: 1.5rem;
      font-weight: 700;
      color: #F8FAFC;
      margin-top: 2.25rem;
      margin-bottom: 1rem;
      padding-bottom: 0.5rem;
      border-bottom: 1px solid rgba(56, 189, 248, 0.2);
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .article-content h2::before {
      content: '';
      display: inline-block;
      width: 4px;
      height: 1.1em;
      background: #38BDF8;
      border-radius: 2px;
      box-shadow: 0 0 8px #38BDF8;
    }
    .article-content h3 {
      font-size: 1.25rem;
      font-weight: 600;
      color: #E2E8F0;
      margin-top: 1.75rem;
      margin-bottom: 0.75rem;
    }
    .article-content p {
      margin-top: 1.25rem;
      margin-bottom: 1.25rem;
      text-align: justify;
    }
    .article-content ul, .article-content ol {
      margin-top: 1rem;
      margin-bottom: 1.25rem;
      padding-left: 1.5rem;
    }
    .article-content li {
      margin-bottom: 0.5rem;
    }
    .article-content blockquote {
      margin: 1.75rem 0;
      padding: 1rem 1.25rem;
      background: rgba(15, 23, 42, 0.7);
      border-left: 4px solid #38BDF8;
      border-radius: 0 8px 8px 0;
      color: #94A3B8;
      font-style: normal;
    }
    .article-content code {
      background: rgba(30, 41, 59, 0.8);
      color: #38BDF8;
      padding: 0.15rem 0.4rem;
      border-radius: 4px;
      font-family: monospace;
      font-size: 0.9em;
    }
    .article-content pre {
      background: #0B132B;
      border: 1px solid rgba(56, 189, 248, 0.2);
      border-radius: 8px;
      padding: 1.25rem;
      overflow-x: auto;
      margin: 1.5rem 0;
    }
    .article-content table {
      width: 100%;
      border-collapse: collapse;
      margin: 1.75rem 0;
      font-size: 0.9rem;
    }
    .article-content th, .article-content td {
      padding: 0.75rem 1rem;
      border: 1px solid rgba(56, 189, 248, 0.15);
      text-align: left;
    }
    .article-content th {
      background: rgba(15, 23, 42, 0.9);
      color: #38BDF8;
      font-weight: 600;
    }
    .article-content tr:nth-child(even) {
      background: rgba(15, 23, 42, 0.4);
    }
    .pulse-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #2DD4BF;
      box-shadow: 0 0 8px #2DD4BF;
      display: inline-block;
    }

/* roulang page: category1 */
:root {
      --bg-dark: #070B14;
      --bg-deep: #040711;
      --card-bg: rgba(16, 27, 59, 0.65);
      --card-border: rgba(56, 189, 248, 0.16);
      --accent-cyan: #38BDF8;
      --accent-teal: #2DD4BF;
      --text-main: #F8FAFC;
      --text-muted: #94A3B8;
      --text-dim: #64748B;
    }
    body {
      background-color: var(--bg-dark);
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      overflow-x: hidden;
      margin: 0;
    }
    .glass-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
      transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .glass-card:hover {
      border-color: rgba(56, 189, 248, 0.4);
      background: rgba(22, 36, 75, 0.72);
      transform: translateY(-3px);
      box-shadow: 0 14px 34px -4px rgba(56, 189, 248, 0.22);
    }
    .btn-glow {
      background: linear-gradient(135deg, #0284C7 0%, #38BDF8 100%);
      box-shadow: 0 0 16px rgba(56, 189, 248, 0.35);
      transition: all 0.25s ease;
    }
    .btn-glow:hover {
      transform: translateY(-2px);
      box-shadow: 0 0 26px rgba(56, 189, 248, 0.65);
    }
    .btn-ghost {
      border: 1px solid rgba(56, 189, 248, 0.3);
      background: rgba(15, 23, 42, 0.6);
      transition: all 0.25s ease;
    }
    .btn-ghost:hover {
      background: rgba(56, 189, 248, 0.15);
      border-color: #38BDF8;
      transform: translateY(-1px);
    }
    .nav-active-line {
      position: relative;
    }
    .nav-active-line::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 100%;
      height: 2px;
      background: linear-gradient(90deg, #38BDF8, #2DD4BF);
      border-radius: 9999px;
      box-shadow: 0 0 8px #38BDF8;
    }
    .pulse-dot {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #2DD4BF;
      box-shadow: 0 0 10px #2DD4BF;
      display: inline-block;
      animation: pulseAnimation 2s infinite;
    }
    @keyframes pulseAnimation {
      0% { transform: scale(0.95); opacity: 0.8; }
      50% { transform: scale(1.2); opacity: 1; box-shadow: 0 0 14px #2DD4BF; }
      100% { transform: scale(0.95); opacity: 0.8; }
    }
    .filter-chip.active {
      background: rgba(56, 189, 248, 0.18);
      border-color: #38BDF8;
      color: #38BDF8;
    }
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease-out;
    }
    .faq-item.active .faq-content {
      max-height: 260px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(180deg);
    }
    .faq-item.active {
      border-color: rgba(56, 189, 248, 0.45);
    }