/* roulang page: index */
:root {
      --amber-earth: #B86B2C;
      --deep-charcoal: #1E1E1E;
      --sandstone-white: #F5F0E8;
      --cool-gray-green: #5D6D5C;
      --bright-copper: #D98A44;
      --copper-hover: #B86B2C;
      --text-secondary: #4A4A4A;
      --border-light: rgba(93,109,92,0.15);
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --glass-bg: rgba(245,240,232,0.75);
      --glass-bg-solid: rgba(245,240,232,0.95);
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
      background-color: var(--sandstone-white);
      color: var(--deep-charcoal);
      line-height: 1.75;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    /* 微纹理背景 */
    .texture-bg {
      position: relative;
    }
    .texture-bg::before {
      content: "";
      position: absolute;
      top: 0; left: 0; width: 100%; height: 100%;
      background-image: repeating-linear-gradient(45deg, rgba(93,109,92,0.05) 0px, rgba(93,109,92,0.05) 1px, transparent 1px, transparent 12px);
      pointer-events: none;
      z-index: 0;
    }
    .texture-bg > * {
      position: relative;
      z-index: 1;
    }
    h1, h2, h3, .metric-number {
      font-weight: 700;
    }
    h1 {
      font-size: clamp(2.5rem, 6vw, 4.2rem);
      letter-spacing: -0.02em;
      line-height: 1.2;
    }
    h2 {
      font-size: clamp(1.75rem, 4vw, 2.5rem);
      font-weight: 600;
    }
    h3 {
      font-size: 1.5rem;
      font-weight: 600;
    }
    .metric-number {
      font-variant-numeric: tabular-nums;
      font-weight: 800;
      font-size: 2.5rem;
      color: var(--amber-earth);
    }
    .btn-primary {
      background-color: var(--bright-copper);
      color: white;
      border-radius: 8px;
      padding: 14px 28px;
      font-weight: 600;
      display: inline-block;
      text-align: center;
      transition: all 0.2s ease;
      border: none;
      cursor: pointer;
      box-shadow: 0 2px 8px rgba(184,107,44,0.2);
    }
    .btn-primary:hover {
      background-color: var(--copper-hover);
      box-shadow: 0 0 0 3px rgba(184,107,44,0.3), 0 4px 16px rgba(184,107,44,0.25);
    }
    .btn-secondary {
      background: transparent;
      color: var(--bright-copper);
      border: 2px solid var(--bright-copper);
      border-radius: 8px;
      padding: 14px 28px;
      font-weight: 600;
      display: inline-block;
      text-align: center;
      transition: all 0.2s ease;
      cursor: pointer;
    }
    .btn-secondary:hover {
      background-color: rgba(217,138,68,0.1);
    }
    .card {
      background: var(--sandstone-white);
      border: 1px solid var(--border-light);
      border-radius: 12px;
      padding: 2rem;
      box-shadow: var(--shadow-sm);
      transition: all 0.25s ease;
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      border-color: var(--cool-gray-green);
    }
    .section-title {
      display: flex;
      align-items: center;
      margin-bottom: 2.5rem;
    }
    .section-title::before {
      content: '';
      display: inline-block;
      width: 40px;
      height: 3px;
      background-color: var(--bright-copper);
      margin-right: 1rem;
      border-radius: 2px;
    }
    .glass-nav {
      background: var(--glass-bg);
      backdrop-filter: blur(16px) saturate(180%);
      -webkit-backdrop-filter: blur(16px) saturate(180%);
      border-bottom: 1px solid rgba(93,109,92,0.2);
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    }
    .glass-nav.scrolled {
      background: var(--glass-bg-solid);
      box-shadow: 0 4px 18px rgba(0,0,0,0.1);
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      cursor: pointer;
      padding: 1.2rem 0;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--deep-charcoal);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      color: var(--text-secondary);
      line-height: 1.8;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.5rem;
      border-left: 3px solid var(--bright-copper);
      padding-left: 1rem;
      background: rgba(184,107,44,0.05);
    }
    .faq-item.active .faq-icon {
      color: var(--cool-gray-green);
    }
    input, textarea {
      background: rgba(255,255,255,0.1);
      border: 1px solid rgba(255,255,255,0.2);
      border-radius: 8px;
      padding: 0.8rem 1rem;
      color: white;
      width: 100%;
      transition: border 0.2s;
    }
    input:focus, textarea:focus {
      outline: none;
      border-color: var(--bright-copper);
      box-shadow: 0 0 0 2px rgba(217,138,68,0.3);
    }
    @media (max-width: 768px) {
      .glass-nav {
        background: rgba(245,240,232,0.92);
      }
      .metric-number {
        font-size: 2rem;
      }
    }
    .hover\:glow:hover {
      box-shadow: 0 0 0 3px rgba(184,107,44,0.25);
    }