/* roulang page: index */
:root {
      --primary: #0A0F1E;
      --accent-red: #E94E3C;
      --accent-teal: #00B4A6;
      --bg-warm: #F5F3F0;
      --white: #FFFFFF;
      --text-dark: #1A1A1A;
      --text-mid: #5A5A5A;
      --text-light: #9A9A9A;
      --border-light: rgba(0,0,0,0.04);
      --border-input: #D0D0D0;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --radius-sm: 6px;
      --radius-md: 8px;
      --radius-pill: 40px;
      --font-stack: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-stack);
      background-color: var(--bg-warm);
      color: var(--text-dark);
      margin: 0;
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-weight: 600;
      line-height: 1.2;
      color: var(--primary);
    }

    h1 {
      font-size: 3.2rem;
      font-weight: 700;
      letter-spacing: -0.02em;
    }

    h2 {
      font-size: 2rem;
      font-weight: 600;
      text-align: center;
      margin-bottom: 1rem;
      position: relative;
    }

    h2::after {
      content: '';
      display: block;
      width: 40px;
      height: 3px;
      background: var(--accent-red);
      margin: 0.5rem auto 0;
      border-radius: 2px;
    }

    h3 {
      font-size: 1.25rem;
      font-weight: 600;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 40px;
    }

    @media (max-width: 640px) {
      .container {
        padding: 0 20px;
      }
      h1 {
        font-size: 2.4rem;
      }
      h2 {
        font-size: 1.8rem;
      }
    }

    /* 导航 */
    .main-nav {
      position: fixed;
      top: 20px;
      left: 50%;
      transform: translateX(-50%);
      width: calc(100% - 40px);
      max-width: 1100px;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-pill);
      padding: 8px 24px;
      box-shadow: 0 4px 20px rgba(0,0,0,0.06);
      z-index: 1000;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .logo {
      font-weight: 700;
      font-size: 1.4rem;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .logo i {
      color: var(--accent-red);
      font-size: 1.8rem;
    }

    .nav-links {
      display: flex;
      gap: 28px;
      list-style: none;
      margin: 0;
    }

    .nav-links a {
      text-decoration: none;
      color: var(--text-mid);
      font-weight: 500;
      font-size: 0.95rem;
      transition: color 0.2s;
      position: relative;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-red);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent-red);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary);
      cursor: pointer;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: var(--primary);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2rem;
      z-index: 999;
      transform: translateX(100%);
      transition: transform 0.3s ease;
    }

    .mobile-menu.open {
      transform: translateX(0);
    }

    .mobile-menu a {
      color: white;
      font-size: 2rem;
      text-decoration: none;
      font-weight: 500;
    }

    .close-mobile {
      position: absolute;
      top: 30px;
      right: 30px;
      background: none;
      border: none;
      color: white;
      font-size: 2rem;
    }

    /* Hero */
    .hero {
      padding: 160px 0 100px;
      display: flex;
      align-items: center;
      gap: 60px;
    }

    .hero-left {
      flex: 0 0 60%;
    }

    .hero-right {
      flex: 0 0 40%;
    }

    .hero-tag {
      font-size: 0.85rem;
      text-transform: uppercase;
      letter-spacing: 0.05em;
      color: var(--accent-red);
      font-weight: 600;
      margin-bottom: 1rem;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .hero-tag::before {
      content: '';
      width: 30px;
      height: 2px;
      background: var(--accent-red);
    }

    .hero h1 {
      margin-bottom: 1.5rem;
    }

    .hero-sub {
      font-size: 1.15rem;
      color: var(--text-mid);
      max-width: 480px;
      margin-bottom: 2rem;
    }

    .hero-cta {
      display: flex;
      gap: 16px;
      margin-bottom: 2.5rem;
    }

    .btn-primary {
      background: var(--accent-red);
      color: white;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      cursor: pointer;
      transition: all 0.2s;
      text-decoration: none;
      display: inline-block;
    }

    .btn-primary:hover {
      background: #C03A2C;
      box-shadow: 0 4px 12px rgba(233,78,60,0.3);
    }

    .btn-secondary {
      background: transparent;
      border: 2px solid var(--accent-red);
      color: var(--accent-red);
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      cursor: pointer;
      transition: all 0.2s;
      text-decoration: none;
      display: inline-block;
    }

    .btn-secondary:hover {
      background: var(--accent-red);
      color: white;
    }

    .trust-badge {
      font-size: 0.9rem;
      color: var(--text-light);
      display: flex;
      gap: 20px;
    }

    .hero-right img {
      width: 100%;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-hover);
      animation: fadeInRight 0.8s ease;
    }

    @keyframes fadeInRight {
      from { opacity: 0; transform: translateX(40px); }
      to { opacity: 1; transform: translateX(0); }
    }

    @media (max-width: 768px) {
      .hero {
        flex-direction: column;
        padding: 120px 20px 60px;
      }
      .hero-left, .hero-right {
        flex: 1 1 auto;
      }
    }

    /* 通用区块 */
    section {
      padding: 100px 0;
    }

    @media (max-width: 640px) {
      section {
        padding: 60px 0;
      }
    }

    /* 优势网格 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 3rem;
    }

    .adv-card {
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
    }

    .adv-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent-red);
    }

    .adv-icon {
      font-size: 2rem;
      color: var(--accent-red);
      margin-bottom: 1rem;
    }

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

    @media (max-width: 640px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 方案对比 */
    .pricing-table {
      display: flex;
      gap: 20px;
      margin-top: 3rem;
      justify-content: center;
    }

    .plan-card {
      background: white;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 32px;
      flex: 1;
      transition: all 0.3s;
      text-align: center;
    }

    .plan-card.recommended {
      background: var(--accent-red);
      color: white;
      transform: scale(1.02);
      border: none;
    }

    .plan-card.recommended h3,
    .plan-card.recommended .price {
      color: white;
    }

    .plan-card:hover {
      transform: scale(1.02);
      border-color: var(--accent-red);
    }

    .plan-card.recommended:hover {
      transform: scale(1.03);
    }

    .price {
      font-size: 2rem;
      font-weight: 700;
      color: var(--primary);
      margin: 1rem 0;
    }

    .feature-list {
      list-style: none;
      padding: 0;
      text-align: left;
      margin: 1.5rem 0;
    }

    .feature-list li {
      margin: 0.8rem 0;
      color: var(--text-mid);
    }

    .feature-list i.fa-check {
      color: var(--accent-teal);
      margin-right: 8px;
    }

    .feature-list i.fa-minus {
      color: #ccc;
      margin-right: 8px;
    }

    .badge-popular {
      background: white;
      color: var(--accent-red);
      font-weight: 600;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
    }

    @media (max-width: 768px) {
      .pricing-table {
        flex-direction: column;
      }
    }

    /* 案例瀑布流 */
    .masonry {
      column-count: 3;
      column-gap: 20px;
      margin-top: 3rem;
    }

    .case-card {
      break-inside: avoid;
      margin-bottom: 20px;
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all 0.3s;
    }

    .case-card:hover {
      box-shadow: var(--shadow-hover);
    }

    .case-img {
      width: 100%;
      display: block;
      transition: transform 0.3s;
    }

    .case-card:hover .case-img {
      transform: scale(1.05);
    }

    .case-info {
      padding: 16px;
    }

    .case-tag {
      color: var(--accent-teal);
      font-weight: 600;
      font-size: 0.9rem;
    }

    @media (max-width: 1024px) {
      .masonry {
        column-count: 2;
      }
    }

    @media (max-width: 640px) {
      .masonry {
        column-count: 1;
      }
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 3rem auto 0;
    }

    .faq-item {
      border-bottom: 1px solid #E0E0E0;
      padding: 16px 0;
      cursor: pointer;
    }

    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
      color: var(--text-mid);
    }

    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }

    .faq-item.open {
      border-left: 3px solid var(--accent-red);
      padding-left: 16px;
    }

    /* CTA 区块 */
    .cta-full {
      background: var(--accent-red);
      color: white;
      text-align: center;
      padding: 80px 0;
      position: relative;
    }

    .cta-form {
      max-width: 500px;
      margin: 2rem auto 0;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .cta-form input,
    .cta-form textarea {
      background: rgba(255,255,255,0.2);
      border: 1px solid rgba(255,255,255,0.5);
      border-radius: var(--radius-sm);
      padding: 12px;
      color: white;
      font-size: 1rem;
    }

    .cta-form input:focus,
    .cta-form textarea:focus {
      outline: none;
      border-color: white;
      box-shadow: 0 0 0 3px rgba(255,255,255,0.3);
    }

    .btn-white {
      background: white;
      color: var(--accent-red);
      font-weight: 700;
      border: none;
      padding: 14px;
      border-radius: var(--radius-sm);
      cursor: pointer;
    }

    /* 页脚 */
    footer {
      background: var(--primary);
      color: #B0B0B0;
      padding: 60px 0 20px;
    }

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

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

    .footer-col a {
      color: #B0B0B0;
      text-decoration: none;
      display: block;
      margin: 8px 0;
      transition: color 0.2s;
    }

    .footer-col a:hover {
      color: var(--accent-teal);
    }

    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      text-align: center;
      font-size: 0.9rem;
    }