/* roulang page: index */
/* ----- 设计变量 ----- */
    :root {
      --primary-red: #E0433A;
      --deep-black: #0F1117;
      --data-white: #F7F7F9;
      --victory-gold: #C9A96E;
      --calm-gray: #6B7280;
      --track-silver: #E5E7EB;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Inter', sans-serif;
      --font-number: 'DIN Alternate', 'Helvetica Neue', sans-serif;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(224,67,58,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      --container-max: 1200px;
      --header-height: 72px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--data-white);
      color: #1F2937;
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 700;
      line-height: 1.3;
    }

    h1 { font-size: 48px; letter-spacing: -0.5px; }
    h2 { font-size: 36px; }
    h3 { font-size: 22px; font-weight: 600; }
    h4 { font-size: 18px; font-weight: 600; }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      font-size: 16px;
      border-radius: var(--radius-btn);
      transition: all 0.25s ease;
      cursor: pointer;
      border: none;
      white-space: nowrap;
      font-family: var(--font-body);
      padding: 14px 32px;
    }

    .btn-primary {
      background: var(--primary-red);
      color: white;
      box-shadow: 0 4px 12px rgba(224,67,58,0.3);
    }

    .btn-primary:hover {
      background: #C53030;
      transform: scale(1.03);
      box-shadow: 0 8px 20px rgba(224,67,58,0.4);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-red);
      color: var(--primary-red);
    }

    .btn-outline:hover {
      background: var(--primary-red);
      color: white;
    }

    .btn-ghost {
      background: transparent;
      border: 2px solid white;
      color: white;
    }

    .btn-ghost:hover {
      background: white;
      color: var(--deep-black);
    }

    .btn-lg {
      padding: 18px 42px;
      font-size: 18px;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      height: var(--header-height);
      display: flex;
      align-items: center;
      background: transparent;
      transition: background 0.3s, backdrop-filter 0.3s;
    }

    #header.scrolled {
      background: rgba(15, 17, 23, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(229, 231, 235, 0.1);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 24px;
      color: white;
      letter-spacing: 1px;
    }

    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary-red);
      border-radius: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
      position: relative;
    }

    .logo-icon::after {
      content: '';
      position: absolute;
      width: 6px;
      height: 6px;
      background: var(--victory-gold);
      border-radius: 50%;
      top: 4px;
      right: 4px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-links a {
      color: rgba(255,255,255,0.85);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 4px 0;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-red);
      transition: width 0.2s;
    }

    .nav-links a:hover {
      color: white;
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: white;
      transition: 0.3s;
    }

    .mobile-menu {
      display: none;
    }

    /* Hero */
    #hero {
      background: var(--deep-black);
      padding: 140px 0 100px;
      position: relative;
      overflow: hidden;
    }

    #hero::before {
      content: '';
      position: absolute;
      top: -20%;
      left: -10%;
      width: 120%;
      height: 140%;
      background: repeating-linear-gradient(15deg, rgba(224,67,58,0.08) 0px, rgba(224,67,58,0.08) 2px, transparent 2px, transparent 8px);
      pointer-events: none;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      position: relative;
      z-index: 2;
    }

    .hero-content {
      color: white;
    }

    .hero-content h1 {
      color: white;
      margin-bottom: 20px;
    }

    .hero-content p {
      font-size: 18px;
      color: var(--calm-gray);
      max-width: 480px;
      margin-bottom: 32px;
    }

    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .hero-image {
      position: relative;
      display: flex;
      justify-content: center;
    }

    .hero-image img {
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
      position: relative;
      z-index: 2;
      width: 100%;
      max-width: 520px;
    }

    .hero-glow {
      position: absolute;
      width: 300px;
      height: 300px;
      background: radial-gradient(circle, rgba(201,169,110,0.25) 0%, transparent 70%);
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      border-radius: 50%;
      z-index: 1;
    }

    /* 通用区块 */
    section {
      padding: 90px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }

    .section-title h2 {
      color: var(--deep-black);
      margin-bottom: 12px;
    }

    .section-title p {
      color: var(--calm-gray);
      font-size: 18px;
      max-width: 600px;
      margin: 0 auto;
    }

    /* 核心价值 非对称 */
    #value .grid-value {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 24px;
    }

    .value-large {
      background: white;
      border-radius: var(--radius-card);
      padding: 40px;
      border: 1px solid var(--track-silver);
      transition: var(--transition-smooth);
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .value-large:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
      border-left: 3px solid var(--primary-red);
    }

    .value-small-group {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }

    .value-small {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      border: 1px solid var(--track-silver);
      transition: var(--transition-smooth);
    }

    .value-small:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
      border-left: 3px solid var(--primary-red);
    }

    .icon-gold {
      color: var(--victory-gold);
      font-size: 28px;
      margin-bottom: 16px;
    }

    /* 功能分组 */
    #features .feature-row {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 64px;
      align-items: center;
    }

    .feature-list {
      list-style: none;
    }

    .feature-item {
      display: flex;
      gap: 20px;
      margin-bottom: 40px;
      transition: 0.2s;
      cursor: default;
    }

    .feature-num {
      font-family: var(--font-number);
      font-size: 28px;
      color: rgba(224,67,58,0.4);
      font-weight: 700;
      line-height: 1;
      min-width: 40px;
    }

    .feature-item:hover .feature-num {
      color: var(--primary-red);
    }

    .feature-text h3 {
      margin-bottom: 6px;
    }

    .feature-img img {
      border-radius: 12px;
      box-shadow: var(--shadow-card);
    }

    /* 场景卡片 */
    .scenario-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scroll-snap-type: x mandatory;
    }

    .scenario-card {
      min-width: 320px;
      background: white;
      border-radius: var(--radius-card);
      border: 1px solid var(--track-silver);
      overflow: hidden;
      transition: var(--transition-smooth);
      scroll-snap-align: start;
    }

    .scenario-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .scenario-card img {
      height: 180px;
      object-fit: cover;
      width: 100%;
    }

    .scenario-info {
      padding: 20px;
    }

    .tag {
      display: inline-block;
      background: var(--track-silver);
      color: var(--calm-gray);
      font-size: 12px;
      padding: 4px 10px;
      border-radius: var(--radius-tag);
      margin-bottom: 8px;
    }

    /* 案例深色 */
    #cases {
      background: var(--deep-black);
      color: white;
    }

    .stats-grid {
      display: flex;
      justify-content: center;
      gap: 80px;
      margin: 48px 0;
      flex-wrap: wrap;
    }

    .stat-item {
      text-align: center;
    }

    .stat-number {
      font-family: var(--font-number);
      font-size: 56px;
      color: var(--victory-gold);
      font-weight: 700;
    }

    .logo-row {
      display: flex;
      justify-content: center;
      gap: 48px;
      margin-top: 40px;
    }

    .logo-row img {
      filter: grayscale(100%);
      opacity: 0.7;
      transition: 0.3s;
      height: 48px;
    }

    .logo-row img:hover {
      filter: grayscale(0%);
      opacity: 1;
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
      max-width: 900px;
      margin: 0 auto;
    }

    .pricing-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 40px;
      border: 1px solid var(--track-silver);
      transition: var(--transition-smooth);
      position: relative;
    }

    .pricing-card.recommended {
      border: 1px solid var(--victory-gold);
      box-shadow: 0 0 20px rgba(201,169,110,0.3);
      transform: scale(1.02);
    }

    .badge {
      background: var(--primary-red);
      color: white;
      font-size: 12px;
      padding: 4px 12px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      right: 20px;
    }

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

    .faq-item {
      border-bottom: 1px solid var(--track-silver);
      padding: 20px 0;
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--calm-gray);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }

    /* CTA 尾板 */
    #cta {
      background: var(--deep-black);
      text-align: center;
    }

    /* Footer */
    #footer {
      background: #0A0C10;
      color: var(--calm-gray);
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 40px; }
      .hero-grid, .feature-row { grid-template-columns: 1fr; }
      #value .grid-value { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links, .nav-cta { display: none; }
      .hamburger { display: flex; }
      .mobile-menu.active { display: flex; flex-direction: column; position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: var(--deep-black); justify-content: center; align-items: center; gap: 32px; z-index: 99; }
      .mobile-menu a { color: white; font-size: 20px; }
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      .container { padding: 0 20px; }
    }