/* roulang page: index */
/* ----- 设计变量与重置 ----- */
    :root {
      --red: #D32F2F;
      --red-hover: #B71C1C;
      --charcoal: #1E1E1E;
      --gold: #F5A623;
      --light-bg: #FAFAFA;
      --white: #ffffff;
      --gray: #666666;
      --light-gray: #F0F0F0;
      --text-main: #1E1E1E;
      --text-soft: #555;
      --border-light: #e0e0e0;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Inter', system-ui, -apple-system, sans-serif;
      --max-width: 1280px;
      --section-gap: 100px;
      --card-pad: 24px 28px;
      --transition: all 0.3s cubic-bezier(0.25,0.8,0.25,1);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background: var(--light-bg);
      color: var(--text-main);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, input, textarea {
      font-family: inherit;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    section {
      padding: var(--section-gap) 0;
    }
    h1, h2, h3 {
      font-weight: 700;
      line-height: 1.3;
    }
    h1 { font-size: 38px; font-weight: 800; }
    h2 { font-size: 28px; margin-bottom: 1.5rem; }
    h3 { font-size: 20px; }
    p {
      font-size: 16px;
      line-height: 26px;
      color: var(--text-soft);
    }
    .text-red { color: var(--red); }
    .text-gold { color: var(--gold); }
    
    /* ----- 导航栏 ----- */
    .nav-bar {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(16px);
      height: 72px;
      display: flex;
      align-items: center;
      transition: var(--transition);
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
    }
    .nav-container {
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      font-size: 24px;
      font-weight: 800;
      color: var(--red);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      font-size: 28px;
      color: var(--gold);
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }
    .nav-links a {
      font-weight: 600;
      font-size: 15px;
      color: var(--charcoal);
      position: relative;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--red);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--red);
      transition: var(--transition);
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .burger {
      display: none;
      font-size: 26px;
      cursor: pointer;
      color: var(--charcoal);
    }
    /* 移动端导航面板 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      height: calc(100vh - 72px);
      background: rgba(30,30,30,0.98);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2.5rem;
      z-index: 99;
    }
    .mobile-menu a {
      font-size: 24px;
      font-weight: 700;
      color: white;
    }
    .mobile-menu a:hover {
      color: var(--gold);
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition);
      cursor: pointer;
      border: none;
      background: transparent;
      line-height: 1.2;
      letter-spacing: 0.3px;
    }
    .btn-primary {
      background: var(--red);
      color: white;
      box-shadow: 0 4px 14px rgba(211,47,47,0.25);
    }
    .btn-primary:hover {
      background: var(--red-hover);
      transform: scale(1.03);
      box-shadow: 0 6px 18px rgba(183,28,28,0.35);
    }
    .btn-outline {
      border: 2px solid var(--red);
      color: var(--red);
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(211,47,47,0.06);
      transform: scale(1.03);
    }
    .btn-gold {
      background: var(--gold);
      color: #1E1E1E;
      font-weight: 700;
    }
    .btn-gold:hover {
      background: #e69518;
      transform: scale(1.03);
    }

    /* 首屏 Hero */
    .hero {
      background: linear-gradient(135deg, #FAFAFA 0%, #f5f5f5 100%);
      padding: 40px 0 80px;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }
    .hero-left {
      flex: 1 1 55%;
    }
    .hero-left h1 {
      font-size: 44px;
      background: linear-gradient(135deg, #D32F2F 20%, #F5A623);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.5rem;
    }
    .hero-left .subtitle {
      font-size: 18px;
      color: var(--text-soft);
      margin-bottom: 2rem;
    }
    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .hero-right {
      flex: 1 1 45%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 360px;
      border-radius: 20px;
      box-shadow: var(--shadow-hover);
      position: relative;
      transition: transform 0.3s ease;
    }
    .hero-right:hover {
      transform: scale(1.02) rotate(0.5deg);
    }

    /* 亮点网格 非对称 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 2rem;
    }
    .feature-card {
      background: var(--white);
      padding: var(--card-pad);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
      border-color: var(--red);
    }
    .feature-card i {
      font-size: 32px;
      color: var(--gold);
      margin-bottom: 1rem;
      display: block;
    }
    .second-row {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
      margin-top: 24px;
      max-width: 860px;
      margin-left: auto;
      margin-right: auto;
    }

    /* 案例瀑布流 */
    .cases-masonry {
      columns: 3 280px;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      position: relative;
      overflow: hidden;
    }
    .case-img img {
      transition: transform 0.4s ease;
      width: 100%;
    }
    .case-card:hover .case-img img {
      transform: scale(1.05);
    }
    .case-overlay {
      position: absolute;
      inset: 0;
      background: rgba(30,30,30,0.5);
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: 0.3s;
      color: white;
      font-weight: 700;
    }
    .case-card:hover .case-overlay {
      opacity: 1;
    }
    .case-info {
      padding: 18px;
    }

    /* 对比表 */
    .compare-table {
      display: flex;
      gap: 1rem;
      margin-top: 2rem;
      flex-wrap: wrap;
    }
    .plan-card {
      flex: 1 1 180px;
      background: white;
      border-radius: var(--radius-card);
      padding: 28px 16px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      border: 2px solid transparent;
    }
    .plan-highlight {
      border-color: var(--red);
      background: #fff5f5;
    }
    .plan-highlight h3 {
      color: var(--red);
    }
    .plan-price {
      font-size: 24px;
      font-weight: 800;
      margin: 12px 0;
    }
    .feature-list {
      list-style: none;
      text-align: left;
      padding: 0 10px;
      margin: 20px 0;
    }
    .feature-list li {
      padding: 6px 0;
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      box-shadow: var(--shadow-sm);
    }
    .faq-question {
      padding: 18px 24px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      transition: 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #f9f9f9;
      padding: 0 24px;
    }
    .faq-item.active .faq-answer {
      max-height: 150px;
      padding: 18px 24px;
    }

    /* CTA 深色区 */
    .cta-dark {
      background: var(--charcoal);
      color: white;
      text-align: center;
    }
    .cta-form {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
      justify-content: center;
      margin-top: 2rem;
    }
    .cta-form input {
      padding: 14px;
      border-radius: var(--radius-btn);
      border: 1px solid rgba(255,255,255,0.3);
      background: rgba(255,255,255,0.1);
      color: white;
      min-width: 200px;
    }
    .cta-form input:focus {
      border-color: var(--gold);
      outline: none;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 2rem;
      color: #aaa;
    }

    @media (max-width: 1024px) {
      .hero-grid { flex-direction: column; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .second-row { grid-template-columns: 1fr; max-width: 100%; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .burger { display: block; }
      .features-grid, .cases-masonry { columns: 1; }
      .compare-table { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
    }