/* roulang page: index */
:root {
      --deep-space: #0A0E17;
      --warm-gold: #C9A84C;
      --deep-blue-gray: #1A2332;
      --electric-green: #00E5A0;
      --text-primary: #F0F0F0;
      --text-body: #A0AAB5;
      --text-muted: #6B7280;
      --card-bg: #141B26;
      --card-border: rgba(201, 168, 76, 0.12);
      --gold-glow: rgba(201, 168, 76, 0.08);
      --radius-card: 8px;
      --radius-btn: 4px;
      --radius-round: 50%;
      --shadow-hover: 0 8px 32px rgba(201, 168, 76, 0.08);
      --transition-smooth: 300ms ease-out;
      --font-sans: system-ui, -apple-system, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --container-max: 1280px;
      --section-gap-desktop: 120px;
      --section-gap-tablet: 80px;
      --section-gap-mobile: 60px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--deep-space);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition-smooth);
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all var(--transition-smooth);
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 32px;
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 24px;
      }
    }

    /* 导航栏 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 64px;
      display: flex;
      align-items: center;
      background: transparent;
      transition: background 0.3s ease, box-shadow 0.3s ease;
    }

    .main-header.scrolled {
      background: var(--deep-space);
      border-bottom: 1px solid var(--warm-gold);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--warm-gold);
      letter-spacing: -0.02em;
      white-space: nowrap;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-body);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--warm-gold);
      border-bottom-color: var(--warm-gold);
    }

    .btn-gold-sm {
      background: var(--warm-gold);
      color: var(--deep-space);
      font-weight: 600;
      padding: 8px 20px;
      border-radius: var(--radius-btn);
      font-size: 14px;
      letter-spacing: 0.02em;
    }

    .btn-gold-sm:hover {
      background: #D4B65A;
      transform: scale(1.03);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--warm-gold);
      transition: all 0.3s;
    }

    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        max-width: 320px;
        height: 100vh;
        background: var(--deep-space);
        flex-direction: column;
        justify-content: center;
        gap: 40px;
        transition: right 0.3s ease;
        box-shadow: -5px 0 20px rgba(0,0,0,0.5);
      }
      .nav-links.open {
        right: 0;
      }
      .nav-links a {
        font-size: 20px;
      }
      .hamburger {
        display: flex;
        z-index: 1001;
      }
      .btn-gold-sm {
        margin-top: 20px;
      }
    }

    /* Hero */
    .hero {
      height: 100vh;
      min-height: 600px;
      display: flex;
      align-items: center;
      position: relative;
      background: radial-gradient(circle at 70% 30%, rgba(201,168,76,0.18) 0%, var(--deep-space) 70%);
      overflow: hidden;
    }

    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: 
        linear-gradient(rgba(201,168,76,0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(201,168,76,0.05) 1px, transparent 1px);
      background-size: 60px 60px;
      pointer-events: none;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
    }

    .hero-tag {
      font-size: 13px;
      letter-spacing: 0.15em;
      color: var(--electric-green);
      text-transform: uppercase;
      margin-bottom: 24px;
      font-weight: 500;
    }

    .hero h1 {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.1;
      background: linear-gradient(135deg, #C9A84C 0%, #E8D48B 70%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 24px;
      letter-spacing: -0.02em;
      animation: fadeInUp 1s ease;
    }

    .hero-sub {
      font-size: 18px;
      max-width: 500px;
      color: var(--text-body);
      margin-bottom: 40px;
      line-height: 1.6;
    }

    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--warm-gold);
      color: var(--deep-space);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-size: 16px;
    }

    .btn-primary:hover {
      background: #D4B65A;
      transform: scale(1.03);
    }

    .btn-outline {
      border: 1.5px solid var(--warm-gold);
      color: var(--warm-gold);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      background: transparent;
    }

    .btn-outline:hover {
      background: rgba(201,168,76,0.1);
    }

    .hero-geo {
      position: absolute;
      right: 5%;
      bottom: 15%;
      width: 240px;
      height: 240px;
      border: 1px solid rgba(201,168,76,0.25);
      transform: rotate(45deg);
      opacity: 0.3;
    }

    @keyframes fadeInUp {
      from { opacity: 0; transform: translateY(30px); }
      to { opacity: 1; transform: translateY(0); }
    }

    @media (max-width: 768px) {
      .hero h1 { font-size: 36px; }
      .hero-sub { font-size: 16px; }
    }

    /* 通用板块标题 */
    .section {
      padding: var(--section-gap-desktop) 0;
    }

    @media (max-width: 1024px) {
      .section { padding: var(--section-gap-tablet) 0; }
    }
    @media (max-width: 768px) {
      .section { padding: var(--section-gap-mobile) 0; }
    }

    .section-title {
      display: flex;
      align-items: center;
      gap: 16px;
      margin-bottom: 48px;
    }

    .section-title h2 {
      font-size: 40px;
      font-weight: 600;
      color: var(--text-primary);
      letter-spacing: -0.02em;
    }

    .title-line {
      width: 4px;
      height: 32px;
      background: var(--warm-gold);
      border-radius: 2px;
    }

    /* 核心优势 不对称卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .feature-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      padding: 32px;
      transition: transform var(--transition-smooth), border-color var(--transition-smooth);
    }

    .feature-card:hover {
      transform: translateY(-4px);
      border-color: var(--warm-gold);
      box-shadow: var(--shadow-hover);
    }

    .feature-card.card-high {
      grid-row: span 2;
    }

    .feature-icon {
      font-size: 40px;
      color: var(--electric-green);
      margin-bottom: 24px;
    }

    .feature-card h3 {
      font-size: 22px;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 12px;
    }

    .feature-desc {
      color: var(--text-body);
      margin-bottom: 16px;
      font-size: 15px;
    }

    .feature-stat {
      font-size: 14px;
      color: var(--warm-gold);
      font-weight: 500;
      letter-spacing: 0.03em;
    }

    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
      .feature-card.card-high {
        grid-row: auto;
      }
    }

    /* 服务板块左右交替 */
    .service-block {
      display: flex;
      align-items: center;
      gap: 80px;
      margin-bottom: 100px;
    }

    .service-block.reverse {
      flex-direction: row-reverse;
    }

    .service-text {
      flex: 1;
    }

    .service-number {
      font-size: 120px;
      font-weight: 700;
      color: rgba(201,168,76,0.15);
      line-height: 1;
      margin-bottom: -20px;
    }

    .service-text h3 {
      font-size: 28px;
      color: var(--text-primary);
      margin-bottom: 16px;
    }

    .service-text p {
      color: var(--text-body);
      margin-bottom: 24px;
      max-width: 450px;
    }

    .link-green {
      color: var(--electric-green);
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      border-bottom: 1px solid transparent;
    }

    .link-green:hover {
      border-bottom-color: var(--electric-green);
    }

    .service-image {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid rgba(201,168,76,0.2);
      transition: transform 0.3s;
    }

    .service-image:hover {
      transform: scale(1.02);
    }

    .service-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 16/9;
    }

    @media (max-width: 768px) {
      .service-block, .service-block.reverse {
        flex-direction: column;
        gap: 40px;
      }
    }

    /* 数据背书 */
    .data-bg {
      background: var(--deep-blue-gray);
      padding: 60px 0;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }

    .stat-item .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--electric-green);
      font-feature-settings: "tnum";
      margin-bottom: 8px;
    }

    .stat-label {
      font-size: 13px;
      text-transform: uppercase;
      letter-spacing: 0.08em;
      color: var(--warm-gold);
    }

    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    /* 案例错位 */
    .cases-layout {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr;
      gap: 16px;
    }

    .case-large, .case-small {
      border-radius: var(--radius-card);
      overflow: hidden;
      position: relative;
      border: 1px solid rgba(201,168,76,0.15);
      transition: transform 0.3s;
    }

    .case-large:hover, .case-small:hover {
      transform: scale(1.02);
    }

    .case-large img, .case-small img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }

    .case-large { height: 480px; }
    .case-small { height: 232px; }

    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      padding: 24px;
      background: linear-gradient(transparent, rgba(0,0,0,0.8));
      color: white;
    }

    .case-tag {
      color: var(--warm-gold);
      font-size: 13px;
      margin-bottom: 4px;
    }

    @media (max-width: 768px) {
      .cases-layout {
        grid-template-columns: 1fr;
      }
      .case-large, .case-small {
        height: 280px;
      }
    }

    /* Tab 解决方案 */
    .tabs-nav {
      display: flex;
      gap: 32px;
      margin-bottom: 32px;
      border-bottom: 1px solid rgba(201,168,76,0.25);
      padding-bottom: 8px;
    }

    .tab-btn {
      font-size: 18px;
      font-weight: 600;
      color: var(--text-body);
      padding: 8px 0;
      border-bottom: 3px solid transparent;
      background: none;
    }

    .tab-btn.active {
      color: var(--warm-gold);
      border-bottom-color: var(--warm-gold);
    }

    .tab-panel {
      background: var(--card-bg);
      padding: 48px;
      border-radius: var(--radius-card);
      display: none;
      animation: fadeInUp 0.4s ease;
    }

    .tab-panel.active {
      display: block;
    }

    @media (max-width: 768px) {
      .tabs-nav {
        flex-direction: column;
        gap: 16px;
      }
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 200px 1fr;
      gap: 48px;
    }

    .faq-filters {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .faq-filter {
      color: var(--text-body);
      font-weight: 500;
      padding: 6px 0;
      border-left: 3px solid transparent;
      padding-left: 12px;
    }

    .faq-filter.active {
      color: var(--warm-gold);
      border-left-color: var(--warm-gold);
    }

    .accordion-item {
      border-bottom: 1px solid rgba(201,168,76,0.15);
      padding: 16px 0;
    }

    .accordion-question {
      font-size: 18px;
      font-weight: 600;
      color: var(--warm-gold);
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }

    .accordion-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-body);
    }

    @media (max-width: 768px) {
      .faq-grid {
        grid-template-columns: 1fr;
      }
      .faq-filters {
        flex-direction: row;
        overflow-x: auto;
      }
    }

    /* 全宽CTA */
    .cta-full {
      background: var(--deep-space);
      position: relative;
      overflow: hidden;
      padding: 100px 0;
      text-align: center;
    }

    .light-sweep {
      position: absolute;
      top: -50%;
      left: -50%;
      width: 200%;
      height: 200%;
      background: linear-gradient(45deg, transparent 40%, rgba(201,168,76,0.08) 50%, transparent 60%);
      animation: sweep 6s infinite linear;
    }

    @keyframes sweep {
      0% { transform: translateX(-100%) translateY(-100%); }
      100% { transform: translateX(100%) translateY(100%); }
    }

    .cta-full h2 {
      font-size: 40px;
      color: var(--text-primary);
      margin-bottom: 16px;
    }

    /* 页脚 */
    .footer {
      background: #0A0E17;
      border-top: 1px solid var(--warm-gold);
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--warm-gold);
      margin-bottom: 12px;
    }

    .footer a {
      color: var(--text-body);
      font-size: 14px;
    }

    .footer a:hover {
      color: var(--warm-gold);
    }

    .copyright {
      text-align: center;
      font-size: 13px;
      color: var(--text-muted);
    }

    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }