/* roulang page: index */
:root {
      --primary-red: #E63946;
      --primary-red-dark: #C1121F;
      --dark-bg: #1D1D1D;
      --darker-bg: #121212;
      --gold: #E9C46A;
      --gold-accent: #F4A261;
      --light-bg: #F8F9FA;
      --white: #FFFFFF;
      --gray-light: #CCCCCC;
      --text-dark: #1D1D1D;
      --text-muted: #555555;
      --border-light: rgba(255,255,255,0.15);
      --border-dark: rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.08);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.15);
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
      --font-display: 'Oswald', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --transition: 0.25s ease;
      --container-max: 1280px;
      --section-padding: 100px 0;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--text-dark);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-display);
      letter-spacing: -0.3px;
    }
    h2 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }
    h2::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 60px;
      height: 4px;
      background: var(--primary-red);
    }
    .section-title {
      margin-bottom: 48px;
    }
    .section-title h2 {
      color: var(--text-dark);
    }
    .dark-section .section-title h2 {
      color: var(--white);
    }
    .dark-section .section-title h2::after {
      background: var(--gold);
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 16px;
      text-decoration: none;
      transition: var(--transition);
      cursor: pointer;
      border: 2px solid transparent;
      letter-spacing: 0.5px;
      line-height: 1.2;
    }
    .btn-primary {
      background: var(--primary-red);
      color: var(--white);
      border-color: var(--primary-red);
    }
    .btn-primary:hover {
      background: var(--primary-red-dark);
      border-color: var(--primary-red-dark);
      transform: scale(1.03);
      box-shadow: 0 8px 20px rgba(230,57,70,0.4);
    }
    .btn-outline-light {
      background: transparent;
      color: var(--white);
      border-color: var(--white);
    }
    .btn-outline-light:hover {
      background: var(--white);
      color: var(--dark-bg);
    }
    .btn-outline-red {
      background: transparent;
      color: var(--primary-red);
      border-color: var(--primary-red);
    }
    .btn-outline-red:hover {
      background: var(--primary-red);
      color: var(--white);
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      color: inherit;
      text-decoration: none;
    }

    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.3s, backdrop-filter 0.3s;
      padding: 16px 0;
    }
    #nav.scrolled {
      background: rgba(18,18,18,0.88);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-family: var(--font-display);
      font-size: 28px;
      font-weight: 700;
      color: var(--white);
      letter-spacing: 1px;
    }
    .logo span {
      color: var(--primary-red);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      color: var(--white);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-red);
      transition: width 0.25s;
    }
    .nav-links a:hover {
      color: var(--primary-red);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .nav-cta {
      background: var(--primary-red);
      color: white !important;
      padding: 8px 20px !important;
      border-radius: 6px;
      font-weight: 700;
    }
    .nav-cta:hover {
      background: var(--primary-red-dark);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      z-index: 1001;
    }
    .hamburger span {
      width: 28px;
      height: 3px;
      background: white;
      border-radius: 2px;
      transition: 0.3s;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(18,18,18,0.98);
      backdrop-filter: blur(16px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transform: translateY(-100%);
      transition: 0.4s ease;
      z-index: 999;
    }
    .mobile-menu.active {
      transform: translateY(0);
    }
    .mobile-menu a {
      font-size: 22px;
      color: white;
      font-weight: 600;
    }

    /* Hero */
    #hero {
      height: 100vh;
      min-height: 700px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    #hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, rgba(0,0,0,0.4) 0%, rgba(18,18,18,0.85) 100%);
    }
    .hero-content {
      position: relative;
      text-align: center;
      color: white;
      max-width: 900px;
      padding: 0 24px;
    }
    .hero-content h1 {
      font-size: clamp(42px, 8vw, 72px);
      font-weight: 900;
      line-height: 1.1;
      text-transform: uppercase;
    }
    .hero-content h1 .highlight {
      color: var(--gold);
    }
    .hero-sub {
      font-size: 1.25rem;
      margin: 24px 0 36px;
      color: rgba(255,255,255,0.9);
      font-weight: 400;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .particles {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      pointer-events: none;
      overflow: hidden;
    }
    .particle {
      position: absolute;
      background: rgba(255,255,255,0.25);
      border-radius: 50%;
      animation: floatUp 8s infinite;
    }
    @keyframes floatUp {
      0% { transform: translateY(0) scale(1); opacity: 0; }
      10% { opacity: 1; }
      90% { opacity: 0.5; }
      100% { transform: translateY(-100vh) scale(0.2); opacity: 0; }
    }

    /* 通用区块 */
    section {
      padding: var(--section-padding);
    }
    .dark-section {
      background: var(--darker-bg);
      color: var(--white);
    }
    .light-section {
      background: var(--light-bg);
    }

    /* 核心优势 */
    .features-grid {
      display: grid;
      grid-template-columns: 1.4fr 1fr;
      gap: 24px;
    }
    .feature-card {
      background: var(--dark-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      border-left: 5px solid var(--primary-red);
      transition: var(--transition);
      color: white;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 18px 30px rgba(0,0,0,0.5);
      border-left-color: var(--gold);
    }
    .feature-icon {
      font-size: 42px;
      color: var(--primary-red);
      margin-bottom: 20px;
    }
    .feature-card h3 {
      font-size: 24px;
      margin-bottom: 12px;
    }
    .small-cards {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .small-card {
      background: #2a2a2a;
      border-radius: var(--radius-card);
      padding: 24px;
      transition: var(--transition);
      color: white;
    }
    .small-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 12px 24px rgba(0,0,0,0.6);
    }

    /* 场景 */
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .scenario-card {
      height: 280px;
      border-radius: var(--radius-card);
      background-size: cover;
      background-position: center;
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: flex-end;
      padding: 24px;
      transition: 0.3s;
    }
    .scenario-card::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(0deg, rgba(0,0,0,0.75) 0%, rgba(0,0,0,0.2) 60%);
      transition: 0.3s;
    }
    .scenario-card:hover::before {
      background: linear-gradient(0deg, rgba(0,0,0,0.4) 0%, rgba(0,0,0,0.1) 60%);
    }
    .scenario-card:hover {
      transform: scale(1.02);
    }
    .scenario-text {
      position: relative;
      color: white;
    }
    .scenario-text h3 {
      font-size: 24px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .case-card {
      background: #2c2c2c;
      border-radius: var(--radius-card);
      overflow: hidden;
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-8px);
    }
    .case-img {
      height: 240px;
      background-size: cover;
    }
    .case-info {
      padding: 24px;
      color: white;
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pricing-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 40px 28px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .pricing-card.featured {
      border: 2px solid var(--gold);
      transform: scale(1.03);
    }
    .pricing-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
    }
    .price {
      font-size: 48px;
      font-weight: 900;
      color: var(--primary-red);
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: 8px;
      margin-bottom: 12px;
      box-shadow: 0 2px 10px rgba(0,0,0,0.04);
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding: 0 24px;
      color: #444;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }

    /* CTA */
    #contact {
      background: url('/assets/images/backpic/back-2.webp') center/cover;
      position: relative;
      padding: 100px 0;
    }
    #contact::before {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(0,0,0,0.7);
    }
    .cta-content {
      position: relative;
      text-align: center;
      color: white;
    }

    /* 页脚 */
    #footer {
      background: #0a0a0a;
      color: #aaa;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 992px) {
      .features-grid, .scenarios-grid, .cases-grid, .pricing-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .footer-grid { grid-template-columns: 1fr; }
    }