/* roulang page: index */
/* ========== CSS 变量与全局重置 ========== */
    :root {
      --primary-gold: #FF6B35;
      --primary-gold-light: #F7931E;
      --primary-gradient: linear-gradient(135deg, #FF6B35 0%, #F7931E 100%);
      --secondary-purple: #2D1B4E;
      --secondary-purple-dark: #1A0F2E;
      --accent-cyan: #00F2FE;
      --neutral-white: #FFFFFF;
      --neutral-bg: #F8F9FA;
      --neutral-dark: #1E1E1E;
      --neutral-gray: #6C757D;
      --card-bg-light: rgba(255,255,255,0.9);
      --card-shadow: 0 20px 40px rgba(45, 27, 78, 0.12);
      --card-shadow-hover: 0 25px 50px rgba(45, 27, 78, 0.2);
      --btn-shadow: 0 8px 18px rgba(255, 107, 53, 0.35);
      --radius-card: 24px;
      --radius-btn: 12px;
      --radius-small: 8px;
      --font-title: 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --font-body: 'Inter', 'Noto Sans SC', sans-serif;
      --font-number: 'Oswald', 'DIN Alternate', sans-serif;
      --transition: all 0.3s ease;
    }

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

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

    body {
      font-family: var(--font-body);
      background-color: var(--neutral-bg);
      color: var(--neutral-dark);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    /* 容器与布局 */
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
      width: 100%;
    }

    section {
      padding: 120px 0;
      position: relative;
    }

    @media (max-width: 1024px) {
      section {
        padding: 90px 0;
      }
      .container {
        padding: 0 24px;
      }
    }

    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
      .container {
        padding: 0 20px;
      }
    }

    /* 标题体系 */
    h1, h2, h3 {
      font-family: var(--font-title);
      font-weight: 700;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 42px;
      line-height: 1.3;
      margin-bottom: 16px;
    }

    h3 {
      font-size: 24px;
      margin-bottom: 12px;
    }

    .section-subtitle {
      font-size: 18px;
      color: var(--neutral-gray);
      margin-bottom: 56px;
      max-width: 700px;
    }

    /* ========== 导航栏 (桌面+移动) ========== */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: var(--transition);
      padding: 20px 0;
      background: transparent;
    }

    .navbar.scrolled {
      background: var(--secondary-purple);
      box-shadow: 0 10px 30px rgba(0,0,0,0.3);
      padding: 12px 0;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .logo {
      font-family: var(--font-title);
      font-weight: 900;
      font-size: 28px;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 2px;
      transition: var(--transition);
    }

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

    .nav-links a {
      color: white;
      text-decoration: none;
      font-weight: 500;
      font-size: 16px;
      transition: color 0.2s;
      position: relative;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-gradient);
      transition: width 0.3s;
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .btn-nav-cta {
      background: var(--primary-gradient);
      border: none;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      color: white !important;
      font-weight: 700;
      box-shadow: var(--btn-shadow);
      transition: var(--transition);
      margin-left: 16px;
    }

    .btn-nav-cta:hover {
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(255,107,53,0.5);
    }

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

    .hamburger span {
      width: 28px;
      height: 3px;
      background: white;
      transition: 0.3s;
      border-radius: 2px;
    }

    @media (max-width: 1024px) {
      .nav-links {
        gap: 20px;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 100%;
        background: var(--secondary-purple);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: 0.4s ease;
        gap: 40px;
      }
      .nav-links.active {
        right: 0;
      }
      .hamburger {
        display: flex;
        z-index: 1001;
      }
      .btn-nav-cta {
        margin-left: 0;
      }
    }

    /* ========== 首屏 Hero ========== */
    .hero {
      height: 100vh;
      min-height: 700px;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      background: radial-gradient(circle at 50% 40%, #2D1B4E 0%, #0A0515 100%);
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      position: relative;
      color: white;
    }

    .hero-content {
      max-width: 900px;
      z-index: 2;
    }

    .hero h1 {
      font-size: 62px;
      font-weight: 900;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 24px;
      line-height: 1.2;
    }

    .hero-sub {
      font-size: 20px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 40px;
    }

    .hero-cta-group {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary-gradient);
      border: none;
      padding: 16px 40px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      color: white;
      font-size: 18px;
      box-shadow: var(--btn-shadow);
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-primary:hover {
      transform: translateY(-3px);
      box-shadow: 0 15px 30px rgba(255,107,53,0.6);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid white;
      padding: 16px 40px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      color: white;
      font-size: 18px;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-outline:hover {
      background: white;
      color: var(--secondary-purple);
    }

    .floating-badge {
      position: absolute;
      bottom: 60px;
      right: 10%;
      background: rgba(0,0,0,0.6);
      backdrop-filter: blur(10px);
      padding: 12px 24px;
      border-radius: 40px;
      color: var(--accent-cyan);
      font-weight: 700;
      font-size: 20px;
      border-left: 4px solid var(--accent-cyan);
    }

    @media (max-width: 768px) {
      .hero h1 {
        font-size: 40px;
      }
      .floating-badge {
        right: 5%;
        bottom: 30px;
        font-size: 16px;
      }
    }

    /* ========== 通用卡片与网格 ========== */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }

    .card {
      background: white;
      border-radius: var(--radius-card);
      padding: 36px 28px;
      box-shadow: var(--card-shadow);
      transition: var(--transition);
    }

    .card:hover {
      transform: translateY(-8px);
      box-shadow: var(--card-shadow-hover);
    }

    .icon-box {
      font-size: 36px;
      color: var(--primary-gold);
      margin-bottom: 20px;
    }

    .data-badge {
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      font-family: var(--font-number);
      font-size: 28px;
    }

    @media (max-width: 1024px) {
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .grid-3 {
        grid-template-columns: 1fr;
      }
    }

    /* 成就墙 */
    .achievements {
      background: var(--secondary-purple-dark);
      color: white;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 30px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    /* FAQ手风琴 */
    .faq-item {
      background: white;
      border-radius: 16px;
      margin-bottom: 16px;
      padding: 24px;
      box-shadow: 0 4px 12px rgba(0,0,0,0.04);
      cursor: pointer;
      transition: var(--transition);
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 700;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--neutral-gray);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 16px;
    }

    /* CTA区域 */
    .cta-section {
      background: linear-gradient(135deg, #FF6B35 0%, #2D1B4E 100%);
      text-align: center;
      color: white;
    }
    .footer {
      background: #0A0515;
    }