/* roulang page: index */
:root {
      --color-primary: #FF5F1F;
      --color-primary-hover: #E04D0F;
      --color-dark: #0B3D2E;
      --color-dark-stat: #082B20;
      --color-accent: #FFB800;
      --color-bg: #F9FAFB;
      --color-text: #4B5563;
      --color-heading: #1F2937;
      --color-white: #FFFFFF;
      --color-light-gray: #F3F4F6;
      --color-border: #E5E7EB;
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --shadow-card: 0 4px 24px rgba(0,0,0,0.04);
      --shadow-hover: 0 16px 40px rgba(0,0,0,0.10);
      --transition-smooth: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
      --font-mono: "SF Mono","Roboto Mono","Menlo","Consolas",monospace;
      --font-sans: "PingFang SC","Microsoft YaHei","Hiragino Sans GB",-apple-system,sans-serif;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      scroll-padding-top: 80px;
    }
    body {
      font-family: var(--font-sans);
      background: var(--color-bg);
      color: var(--color-text);
      line-height: 1.6;
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    .container {
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      z-index: 100;
      transition: var(--transition-smooth);
      box-shadow: 0 2px 20px rgba(0,0,0,0.03);
    }
    .site-header.scrolled {
      box-shadow: 0 8px 30px rgba(0,0,0,0.08);
      background: rgba(255,255,255,0.98);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 64px;
      padding: 0 24px;
    }
    .logo {
      font-weight: 800;
      font-size: 1.6rem;
      color: var(--color-dark);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.5px;
    }
    .logo-badge {
      width: 28px;
      height: 28px;
      background: var(--color-primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 16px;
      font-weight: bold;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      font-weight: 500;
      color: #374151;
      font-size: 0.98rem;
      transition: var(--transition-smooth);
      position: relative;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--color-primary);
      border-radius: 3px;
      transition: var(--transition-smooth);
    }
    .nav-links a:hover, .nav-links a.nav-active {
      color: var(--color-primary);
    }
    .nav-links a:hover::after, .nav-links a.nav-active::after {
      width: 100%;
    }
    .nav-cta-btn {
      background: var(--color-primary);
      color: white !important;
      padding: 10px 22px;
      border-radius: 30px;
      font-weight: 600;
      margin-left: 8px;
      transition: var(--transition-smooth);
    }
    .nav-cta-btn:hover {
      background: var(--color-primary-hover);
      transform: translateY(-1px);
    }
    .nav-toggle {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .bar {
      width: 28px;
      height: 3px;
      background: var(--color-dark);
      border-radius: 4px;
      transition: 0.3s;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 75%;
      height: 100vh;
      background: var(--color-dark);
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 32px;
      z-index: 101;
      transition: 0.4s ease;
    }
    .mobile-menu.active {
      right: 0;
    }
    body.menu-open {
      overflow: hidden;
    }
    @media (max-width: 850px) {
      .nav-links { display: none; }
      .nav-toggle { display: flex; }
    }
    /* 按钮组件 */
    .btn-primary {
      background: var(--color-primary);
      color: white;
      border: none;
      padding: 14px 36px;
      border-radius: 30px;
      font-weight: 700;
      font-size: 1.one rem;
      white-space: nowrap;
      cursor: pointer;
      transition: var(--transition-smooth);
      display: inline-block;
    }
    .btn-primary:hover {
      background: var(--color-primary-hover);
      transform: translateY(-3px);
      box-shadow: 0 14px 32px rgba(255,95,31,0.35);
    }
    .btn-outline {
      background: transparent;
      color: white;
      border: 2px solid white;
      padding: 12px 32px;
      border-radius: 30px;
      font-weight: 600;
      transition: var(--transition-smooth);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.12);
      border-color: #fff;
    }
    .section-spacing {
      padding: 88px 0;
    }
    @media (max-width: 768px) {
      .section-spacing { padding: 56px 0; }
      
    }
    /* hero 先用简单占位细化 */
    #hero {
      background: linear-gradient(135deg, #0B3D2E 0%, #0A2F24 48%, #071F17 100%);
      color: white;
      min-height: 100vh;
      display: flex;
      align-items: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-blend-mode: overlay;
      background-size: cover;
      background-position: center;
      padding-top: 70px;
    }
    .fact-badge {
      background: rgba(0,0,0,0.25);
      backdrop-filter: blur(8px);
    }