/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary: #0A0E27;
      --secondary: #E94E3C;
      --accent: #F5A623;
      --bg-light: #F9FAFB;
      --bg-card: #FFFFFF;
      --text-main: #0A0E27;
      --text-body: #374151;
      --text-muted: #6B7280;
      --text-on-dark: #FFFFFF;
      --text-on-dark-muted: #D1D5DB;
      --border-light: #F3F4F6;
      --border-subtle: #E5E7EB;
      --radius-lg: 16px;
      --radius-md: 12px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-hover: 0 10px 25px rgba(0,0,0,0.08), 0 4px 10px rgba(0,0,0,0.04);
      --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, input {
      font-family: inherit;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    /* 导航系统 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.02);
      z-index: 50;
      transition: background 0.25s, box-shadow 0.25s;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-weight: 800;
      font-size: 1.5rem;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.02em;
    }
    .logo i {
      color: var(--secondary);
      font-size: 1.8rem;
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      font-weight: 500;
      color: var(--text-body);
    }
    .nav-links a {
      transition: color 0.2s;
      font-size: 0.95rem;
    }
    .nav-links a:hover {
      color: var(--secondary);
    }
    .btn-primary {
      background: var(--secondary);
      color: white;
      padding: 0.7rem 2rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: var(--transition-smooth);
      box-shadow: 0 4px 10px rgba(233,78,60,0.2);
      display: inline-block;
      border: none;
      cursor: pointer;
      font-size: 0.95rem;
    }
    .btn-primary:hover {
      background: #C0392B;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(233,78,60,0.3);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 0.6rem 2rem;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: var(--transition-smooth);
      display: inline-block;
      cursor: pointer;
      font-size: 0.95rem;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
      transform: translateY(-2px);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: var(--primary);
      cursor: pointer;
    }
    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2rem;
      z-index: 60;
      transform: translateX(100%);
      transition: transform 0.35s ease;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 1.5rem;
      font-weight: 600;
      color: var(--primary);
    }
    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 2rem;
      color: var(--primary);
      cursor: pointer;
    }
    /* 区块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 70px 0;
      }
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    /* 滚动渐现动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(30px);
      transition: opacity 0.6s ease-out, transform 0.6s ease-out;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }
    /* 卡片通用样式 */
    .card {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-light);
      transition: var(--transition-smooth);
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    /* 手风琴动画 */
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease-in-out;
    }
    /* 自定义杂志网格与布局细节 */
    .magazine-row {
      display: flex;
      gap: 40px;
      align-items: center;
      margin-bottom: 80px;
    }
    .magazine-row.reverse {
      flex-direction: row-reverse;
    }
    .magazine-text {
      flex: 1;
    }
    .magazine-img {
      flex: 1;
      border-radius: var(--radius-lg);
      overflow: hidden;
    }
    .magazine-img img {
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 16/9;
    }
    .highlight-list {
      list-style: none;
      padding: 0;
    }
    .highlight-list li {
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 10px;
      color: var(--text-body);
    }
    .highlight-list i {
      color: var(--secondary);
    }
    /* 方案对比卡 */
    .compare-card {
      padding: 2rem;
      border-radius: var(--radius-lg);
    }
    .compare-left {
      background: #F3F4F6;
      border: 1px solid var(--border-subtle);
    }
    .compare-right {
      background: rgba(10,14,39,0.03);
      border-left: 4px solid var(--secondary);
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin: 18px 0;
      font-weight: 500;
    }

@keyframes float {
          0% { transform: translateY(0); }
          50% { transform: translateY(-8px); }
          100% { transform: translateY(0); }
        }
        .animate-float { animation: float 4s ease-in-out infinite; }