/* roulang page: index */
:root {
      --red: #C41E3A;
      --red-dark: #9B1B2E;
      --dark: #1E1E1E;
      --bg: #F5F3EF;
      --white: #FFFFFF;
      --charcoal: #2C2C2C;
      --gray: #6B6B6B;
      --gold: #D4AF37;
      --green: #2D5A27;
      --border-light: #E0DDD8;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.12);
      --transition: 0.3s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', sans-serif;
      background-color: var(--bg);
      color: var(--charcoal);
      line-height: 1.7;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, input, textarea {
      font-family: inherit;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      padding: 16px 0;
      transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      background: transparent;
    }
    #header.scrolled {
      background: rgba(30,30,30,0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.15);
      padding: 10px 0;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 4px;
      color: #fff;
    }
    .logo .red-part {
      color: var(--red);
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--red);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="white"><path d="M13.5 2.5c-1.5 0-2.7.9-3.5 2.2-.2.3-.3.7-.3 1.1 0 .8.4 1.5 1 2 .6.5 1.3.8 2 .8.6 0 1.2-.2 1.7-.5l-2.1-3.5c-.3-.5.1-1.1.7-1.1.3 0 .6.1.8.4l2.5 4.2c.5-.3.9-.7 1.2-1.2.4-.6.6-1.3.6-2 0-1.9-1.5-3.4-3.4-3.4zm-3.5 5.6c-1 .4-1.8 1.1-2.3 2-.6.9-.9 2-.9 3.1 0 1.9 1.5 3.4 3.4 3.4s3.4-1.5 3.4-3.4c0-1.3-.5-2.5-1.3-3.4-.8-.9-1.9-1.5-3.1-1.7h.8zm8.5 1.9c-.8 0-1.5.4-2 1-.4.6-.7 1.3-.7 2.1 0 1.4 1.1 2.5 2.5 2.5s2.5-1.1 2.5-2.5-1.1-2.5-2.5-2.5c.5 0 1 .1 1.4.4l-1.9 3.2c-.3.5.1 1.1.7 1.1.3 0 .6-.1.8-.4l2.1-3.5c.6.3 1 .9 1 1.6 0 1-.8 1.8-1.8 1.8s-1.8-.8-1.8-1.8c0-.3.1-.6.2-.9l-1.9 3.2c-.3.5-.8.8-1.4.8-1 0-1.8-.8-1.8-1.8 0-.4.1-.8.3-1.1l1.5-2.5z"/></svg>') no-repeat center;
      mask-size: contain;
      background: #fff;
      display: inline-block;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      font-weight: 500;
      color: rgba(255,255,255,0.9);
    }
    .nav-links a {
      position: relative;
      padding-bottom: 4px;
      font-size: 0.95rem;
      color: #fff;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--gold);
      transition: width 0.25s;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-primary-nav {
      background: var(--red);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 0.9rem;
      border: none;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
      margin-left: 8px;
    }
    .btn-primary-nav:hover {
      background: var(--red-dark);
      transform: translateY(-2px);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      z-index: 1100;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: white;
      transition: 0.3s;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: var(--red);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      transform: translateY(-100%);
      transition: transform 0.4s ease;
      z-index: 1050;
    }
    .mobile-menu.open {
      transform: translateY(0);
    }
    .mobile-menu a {
      color: white;
      font-size: 1.8rem;
      font-weight: 600;
    }
    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 2rem;
      color: white;
      background: none;
      border: none;
      cursor: pointer;
    }
    /* Hero */
    #hero {
      background: linear-gradient(135deg, #1a1a1a 0%, #2c2c2c 100%);
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }
    .hero-bg-img {
      position: absolute;
      right: 0;
      top: 0;
      width: 50%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.55;
    }
    .hero-bg-img::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(196,30,58,0.25) 0%, rgba(30,30,30,0.7) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 600px;
      color: white;
    }
    .hero h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 20px;
    }
    .hero .sub {
      font-size: 1.15rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 40px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-main {
      background: var(--red);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: 0.2s;
    }
    .btn-main:hover {
      background: var(--red-dark);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
    }
    /* 通用 section */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      text-align: center;
      margin-bottom: 16px;
      color: var(--dark);
    }
    .section-sub {
      text-align: center;
      color: var(--gray);
      margin-bottom: 56px;
      font-size: 1.1rem;
    }
    /* 服务卡片 */
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: 0.25s;
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 56px;
      height: 56px;
      background: var(--red);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 20px;
    }
    .service-card h3 {
      font-size: 1.4rem;
      margin-bottom: 12px;
    }
    /* 数据块 */
    #numbers {
      background: var(--dark);
      color: white;
      padding: 80px 0;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
    }
    .stat-item .number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--gold);
    }
    /* 案例 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.25s;
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      height: 220px;
      background-size: cover;
      background-position: center;
    }
    .case-text {
      padding: 20px;
    }
    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
    }
    .step {
      text-align: center;
      flex:1;
    }
    .step-num {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--red);
      color: white;
      font-weight: 700;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 16px;
    }
    /* FAQ */
    .faq-item {
      background: white;
      border-radius: 8px;
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      background: var(--dark);
      color: white;
      padding: 18px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      padding: 0 24px;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: white;
    }
    .faq-item.open .faq-answer {
      padding: 20px 24px;
      max-height: 200px;
    }
    /* 联系 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
    }
    input, textarea {
      width: 100%;
      padding: 14px;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-btn);
      margin-bottom: 16px;
    }
    footer {
      background: var(--dark);
      color: #ccc;
      padding: 48px 0 24px;
    }
    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .hero h1 { font-size: 2.5rem; }
    }
    @media (max-width: 640px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .grid-4, .grid-3 { grid-template-columns: 1fr; }
      .contact-grid { grid-template-columns: 1fr; }
      .hero-bg-img { width: 100%; opacity: 0.3; }
      .stats-grid { gap: 24px; }
      .process-steps { flex-direction: column; gap: 32px; }
    }