/* roulang page: index */
:root {
      --primary-deep: #1A1A1A;
      --accent-red: #C41E3A;
      --accent-gold: #D4AF37;
      --bg-warm: #F8F6F3;
      --card-bg: #FFFFFF;
      --text-body: #2C2C2C;
      --text-secondary: #6B6B6B;
      --text-light: #F5F5F5;
      --border-subtle: #E5E0D9;
      --border-light: rgba(0,0,0,0.06);
      --shadow-card: 0 2px 16px rgba(0,0,0,0.04), 0 0 0 1px rgba(0,0,0,0.03);
      --shadow-card-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", "Helvetica Neue", sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-body);
      margin: 0;
      line-height: 1.7;
      font-size: 16px;
    }
    h1, h2, h3, h4 {
      font-weight: 600;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container-lg {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
    }
    /* 导航 */
    .navbar-custom {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      background: transparent;
      padding: 16px 0;
    }
    .navbar-custom.scrolled {
      background: rgba(248, 246, 243, 0.95);
      backdrop-filter: blur(10px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
    }
    .navbar-brand-custom {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary-deep);
      letter-spacing: -0.01em;
    }
    .nav-link-custom {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-body) !important;
      margin-left: 36px;
      padding: 0 !important;
      transition: color 0.2s;
      position: relative;
    }
    .nav-link-custom::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-gold);
      transition: width 0.25s ease;
    }
    .nav-link-custom:hover::after,
    .nav-link-custom.active::after {
      width: 100%;
    }
    .nav-link-custom.active {
      color: var(--primary-deep) !important;
      font-weight: 600;
    }
    .navbar-toggler {
      border: none;
      padding: 4px;
    }
    .navbar-toggler-icon {
      background-image: none;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      width: 24px;
      height: 24px;
    }
    .navbar-toggler-icon::before,
    .navbar-toggler-icon::after,
    .navbar-toggler-icon span {
      content: '';
      display: block;
      width: 24px;
      height: 2px;
      background: var(--primary-deep);
      margin: 2px 0;
      transition: 0.2s;
    }
    .mobile-menu {
      background: var(--bg-warm);
      backdrop-filter: blur(12px);
    }
    /* Hero */
    #hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      padding-top: 80px;
      background-color: var(--bg-warm);
    }
    .hero-title {
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.15;
      letter-spacing: -0.02em;
      color: var(--primary-deep);
    }
    .hero-sub {
      font-size: 1.125rem;
      color: var(--text-secondary);
      margin: 24px 0 32px;
      max-width: 480px;
    }
    .btn-primary-custom {
      background: var(--accent-red);
      border: none;
      border-radius: var(--radius-btn);
      padding: 14px 36px;
      font-weight: 600;
      font-size: 16px;
      color: white;
      transition: all 0.25s ease;
      display: inline-block;
    }
    .btn-primary-custom:hover {
      background: #A01830;
      transform: scale(1.03);
      box-shadow: 0 8px 20px rgba(196,30,58,0.3);
      color: white;
    }
    .btn-link-custom {
      color: var(--accent-red);
      font-weight: 500;
      border-bottom: 1px solid var(--accent-red);
      padding-bottom: 2px;
      transition: 0.2s;
      margin-left: 24px;
      display: inline-block;
    }
    .btn-link-custom:hover {
      border-bottom-width: 2px;
      color: var(--accent-gold);
      border-color: var(--accent-gold);
    }
    .hero-image-placeholder {
      background: var(--primary-deep);
      min-height: 400px;
      border-radius: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      overflow: hidden;
    }
    /* 区块标题 */
    .section-title {
      font-size: 2.25rem;
      font-weight: 600;
      letter-spacing: -0.01em;
      color: var(--primary-deep);
      margin-bottom: 1rem;
    }
    .section-subtitle {
      color: var(--text-secondary);
      font-size: 1rem;
      max-width: 600px;
      margin: 0 auto 48px;
    }
    /* 通用卡片 */
    .card-custom {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
      border: 1px solid transparent;
      height: 100%;
    }
    .card-custom:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
      border-color: rgba(196,30,58,0.25);
    }
    /* 痛点卡片 */
    .pain-icon {
      font-size: 2rem;
      color: var(--accent-gold);
      margin-bottom: 16px;
    }
    /* 解决方案卡片 */
    .solution-img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      border-radius: 12px 12px 0 0;
    }
    /* 成果区块 */
    .bg-deep {
      background-color: var(--primary-deep);
    }
    .stat-number {
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--accent-red);
      line-height: 1.1;
    }
    .stat-label {
      color: var(--text-light);
      font-size: 1rem;
    }
    /* 证言卡片 */
    .testimonial-card {
      background: var(--card-bg);
      border-left: 3px solid var(--accent-red);
      border-radius: 0 12px 12px 0;
      padding: 32px;
    }
    .testimonial-quote {
      font-style: italic;
      font-size: 1rem;
      line-height: 1.8;
      color: var(--text-body);
      position: relative;
    }
    .testimonial-quote::before {
      content: "“";
      font-size: 3rem;
      color: var(--accent-gold);
      position: absolute;
      left: -20px;
      top: -10px;
      line-height: 1;
    }
    /* FAQ */
    .accordion-custom .accordion-item {
      border: none;
      border-bottom: 1px solid var(--border-subtle);
      background: transparent;
    }
    .accordion-button {
      font-weight: 600;
      font-size: 1.5rem;
      background: transparent;
      box-shadow: none;
      padding: 20px 0;
      color: var(--primary-deep);
    }
    .accordion-button:not(.collapsed) {
      background: transparent;
      color: var(--accent-red);
      box-shadow: none;
    }
    .accordion-button::after {
      transition: transform 0.3s;
    }
    .accordion-body {
      padding: 0 0 20px 24px;
      color: var(--text-secondary);
      border-left: 3px solid var(--accent-red);
      margin-left: 4px;
    }
    /* 表单 */
    .form-control-custom {
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-input);
      padding: 12px 16px;
      background: #fff;
      transition: 0.2s;
    }
    .form-control-custom:focus {
      border-color: var(--accent-red);
      box-shadow: 0 0 0 3px rgba(196,30,58,0.1);
      outline: none;
    }
    .dark-input {
      background: #2C2C2C;
      border-color: #444;
      color: white;
    }
    .dark-input:focus {
      border-color: var(--accent-red);
      box-shadow: 0 0 0 3px rgba(196,30,58,0.4);
    }
    .footer-link {
      color: var(--text-secondary);
      margin-left: 20px;
      transition: color 0.2s;
    }
    .footer-link:hover {
      color: var(--accent-red);
    }
    /* 动画 */
    .fade-in-up {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.6s ease, transform 0.6s ease;
    }
    .fade-in-up.visible {
      opacity: 1;
      transform: translateY(0);
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 2rem;
      }
      .section-title {
        font-size: 1.75rem;
      }
      .stat-number {
        font-size: 2.5rem;
      }
      .navbar-collapse {
        background: var(--bg-warm);
        padding: 24px;
        border-radius: 16px;
        margin-top: 12px;
      }
      .nav-link-custom {
        margin-left: 0;
        padding: 12px 0 !important;
      }
    }