/* roulang page: index */
:root {
      --deep-steel: #1A1C20;
      --burst-gold: #C8A96E;
      --warm-linen: #F5F4F0;
      --text-primary: #1A1C20;
      --text-secondary: #4A4D52;
      --text-muted: #8A8D92;
      --border-light: #E0DDD6;
      --shadow-hard: 4px 4px 0px 0px rgba(26, 28, 32, 0.08);
      --shadow-hover: 8px 8px 0px 0px rgba(26, 28, 32, 0.1);
      --radius-sm: 4px;
      --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-mono: "Inter", "SF Mono", "Roboto Mono", monospace;
      --transition: 0.25s cubic-bezier(0.2, 0.0, 0, 1);
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: var(--warm-linen);
      color: var(--text-primary);
      line-height: 1.8;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
      background-image: repeating-linear-gradient(0deg, transparent, transparent 2px, rgba(26,28,32,0.008) 2px, rgba(26,28,32,0.008) 4px);
      background-size: 100% 4px;
    }
    .container {
      max-width: 1440px;
      margin: 0 auto;
      padding: 0 40px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 24px;
      }
    }
    a {
      color: inherit;
      text-decoration: none;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, input {
      font-family: var(--font-sans);
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 80px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 40px;
      z-index: 50;
      transition: background-color 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      background-color: transparent;
    }
    .navbar.scrolled {
      background-color: rgba(245, 244, 240, 0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 0 0 rgba(26,28,32,0.08);
    }
    .logo {
      font-weight: 800;
      font-size: 1.4rem;
      letter-spacing: 2px;
      color: var(--deep-steel);
      transition: color var(--transition);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      font-size: 0.9rem;
      text-transform: uppercase;
      letter-spacing: 1px;
      font-weight: 500;
      color: var(--deep-steel);
      transition: color var(--transition);
      position: relative;
    }
    .nav-links a:hover {
      color: var(--burst-gold);
    }
    .search-icon {
      font-size: 1.2rem;
      color: var(--deep-steel);
      cursor: pointer;
      transition: color var(--transition);
    }
    .search-icon:hover {
      color: var(--burst-gold);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--deep-steel);
      transition: var(--transition);
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .navbar {
        padding: 0 24px;
      }
    }
    /* Hero */
    .hero {
      padding: 140px 0 80px;
      display: flex;
      align-items: center;
      gap: 60px;
      min-height: 90vh;
    }
    .hero-left {
      flex: 0 0 60%;
    }
    .hero-right {
      flex: 0 0 40%;
      position: relative;
    }
    .hero h1 {
      font-weight: 900;
      font-size: clamp(3.5rem, 8vw, 6rem);
      letter-spacing: -0.03em;
      line-height: 1.1;
      margin-bottom: 24px;
      color: var(--deep-steel);
    }
    .hero h1 .gold-skew {
      color: var(--burst-gold);
      display: inline-block;
      transform: skewX(-5deg);
    }
    .hero-sub {
      font-size: 1.2rem;
      max-width: 45ch;
      color: var(--text-secondary);
      margin-bottom: 40px;
    }
    .hero-image {
      aspect-ratio: 4/3;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-sm);
      box-shadow: var(--shadow-hard);
    }
    .data-card {
      position: absolute;
      bottom: -20px;
      left: 20px;
      right: 20px;
      background: var(--deep-steel);
      padding: 24px;
      border-radius: var(--radius-sm);
      display: flex;
      justify-content: space-around;
      color: white;
      box-shadow: var(--shadow-hard);
    }
    .data-item {
      text-align: center;
    }
    .data-number {
      font-family: var(--font-mono);
      font-size: 2rem;
      font-weight: 700;
      color: var(--burst-gold);
    }
    .data-label {
      font-size: 0.75rem;
      text-transform: uppercase;
      letter-spacing: 1px;
      opacity: 0.8;
    }
    @media (max-width: 768px) {
      .hero {
        flex-direction: column;
        padding: 100px 0 40px;
        gap: 40px;
      }
      .hero-left, .hero-right {
        flex: 1 1 auto;
        width: 100%;
      }
      .hero-right {
        margin-bottom: 40px;
      }
      .data-card {
        position: static;
        margin-top: -20px;
      }
    }
    /* 板块标题 */
    .section-title {
      font-weight: 700;
      font-size: clamp(2rem, 5vw, 3.5rem);
      margin-bottom: 48px;
      display: flex;
      align-items: center;
      gap: 20px;
      color: var(--deep-steel);
    }
    .section-title::before {
      content: '';
      display: block;
      width: 40px;
      height: 4px;
      background: var(--burst-gold);
      flex-shrink: 0;
    }
    /* 亮点网格 */
    .insight-grid {
      display: grid;
      grid-template-columns: 1fr 1.2fr 1fr;
      gap: 40px;
      margin: 80px 0;
    }
    .insight-card {
      padding: 40px 32px;
      border-radius: var(--radius-sm);
      box-shadow: var(--shadow-hard);
      transition: all var(--transition);
      background: white;
    }
    .insight-card.dark {
      background: var(--deep-steel);
      color: white;
    }
    .insight-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .big-number {
      font-family: var(--font-mono);
      font-size: 5rem;
      font-weight: 900;
      line-height: 1;
      margin-bottom: 16px;
    }
    .insight-card:not(.dark) .big-number {
      color: var(--deep-steel);
    }
    .insight-card.dark .big-number {
      color: var(--burst-gold);
    }
    .insight-desc {
      font-size: 1rem;
      color: var(--text-secondary);
      font-weight: 400;
    }
    .insight-card.dark .insight-desc {
      color: rgba(255,255,255,0.8);
    }
    @media (max-width: 768px) {
      .insight-grid {
        grid-template-columns: 1fr;
        gap: 24px;
      }
    }
    /* 案例瀑布流 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 40px;
      margin: 80px 0;
    }
    .case-card {
      border-radius: var(--radius-sm);
      overflow: hidden;
      box-shadow: var(--shadow-hard);
      transition: all var(--transition);
      background: white;
      cursor: pointer;
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      aspect-ratio: 4/3;
      background-size: cover;
      background-position: center;
      filter: grayscale(30%) contrast(1.1);
      transition: filter 0.3s, transform 0.3s;
      position: relative;
    }
    .case-card:hover .case-img {
      filter: grayscale(0%) contrast(1.1);
    }
    .case-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, rgba(200,169,110,0.5) 0%, rgba(26,28,32,0.7) 100%);
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: opacity 0.3s;
      color: white;
      font-weight: 700;
      font-size: 1.1rem;
      letter-spacing: 1px;
    }
    .case-card:hover .case-overlay {
      opacity: 1;
    }
    .case-info {
      padding: 16px;
    }
    .case-name {
      font-weight: 600;
      font-size: 0.95rem;
      margin-bottom: 8px;
    }
    .case-tag {
      font-size: 0.75rem;
      color: var(--burst-gold);
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    @media (max-width: 768px) {
      .case-grid {
        grid-template-columns: 1fr;
        gap: 32px;
      }
    }
    /* 方案对比 */
    .comparison {
      display: grid;
      grid-template-columns: 1fr 1fr;
      background: #F0EFEC;
      border-radius: var(--radius-sm);
      margin: 80px 0;
      position: relative;
    }
    .comparison::before {
      content: '';
      position: absolute;
      left: 50%;
      top: 40px;
      bottom: 40px;
      width: 1px;
      background: #D1CFC9;
      transform: translateX(-50%);
    }
    .comp-col {
      padding: 48px 40px;
    }
    .comp-col h3 {
      font-weight: 700;
      font-size: 1.8rem;
      margin-bottom: 32px;
    }
    .comp-left h3 {
      color: var(--text-muted);
    }
    .comp-right h3 {
      color: var(--deep-steel);
      font-size: 2.2rem;
    }
    .comp-list {
      list-style: none;
      padding: 0;
      margin: 0;
    }
    .comp-list li {
      margin-bottom: 20px;
      padding-left: 20px;
      position: relative;
      color: var(--text-secondary);
    }
    .comp-left .comp-list li::before {
      content: '—';
      position: absolute;
      left: 0;
      color: #ccc;
      font-weight: 300;
    }
    .comp-right .comp-list li::before {
      content: '';
      position: absolute;
      left: 0;
      top: 4px;
      bottom: 4px;
      width: 3px;
      background: var(--burst-gold);
      border-radius: 2px;
    }
    @media (max-width: 768px) {
      .comparison {
        grid-template-columns: 1fr;
      }
      .comparison::before {
        display: none;
      }
      .comp-col {
        padding: 32px 24px;
      }
    }
    /* 联系CTA */
    .contact-section {
      text-align: center;
      padding: 80px 0;
    }
    .contact-title {
      font-size: 2.5rem;
      font-weight: 700;
      margin-bottom: 48px;
      color: var(--deep-steel);
    }
    .contact-form {
      max-width: 480px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 32px;
    }
    .input-line {
      border: none;
      border-bottom: 2px solid var(--border-light);
      padding: 15px 5px;
      background: transparent;
      font-size: 1rem;
      outline: none;
      transition: border-color 0.2s;
      width: 100%;
    }
    .input-line:focus {
      border-bottom-color: var(--deep-steel);
    }
    .submit-btn {
      background: none;
      border: none;
      font-size: 1.3rem;
      font-weight: 700;
      color: var(--burst-gold);
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      transition: gap 0.25s;
      align-self: flex-start;
    }
    .submit-btn:hover {
      gap: 20px;
    }
    .submit-btn i {
      transition: transform 0.25s;
    }
    .submit-btn:hover i {
      transform: translateX(8px);
    }
    /* 页脚 */
    .footer {
      border-top: 1px solid var(--border-light);
      padding: 32px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    .social-icons i {
      font-size: 1.3rem;
      margin-left: 20px;
      color: var(--text-muted);
      transition: color var(--transition);
    }
    .social-icons i:hover {
      color: var(--burst-gold);
    }
    @media (max-width: 768px) {
      .footer {
        flex-direction: column;
        gap: 16px;
        text-align: center;
      }
    }
    /* 通用间距 */
    section {
      scroll-margin-top: 100px;
    }
    .mt-0 { margin-top: 0; }
    .mb-0 { margin-bottom: 0; }
    .text-gold { color: var(--burst-gold); }