/* roulang page: index */
:root {
      --deep-sea: #0B3D5F;
      --coral-glow: #F85C3A;
      --sea-green: #1A6B7A;
      --dark-abyss: #051E2F;
      --soft-gray: #F7F9FC;
      --text-dark: #1E2A38;
      --white: #FFFFFF;
      --border-light: rgba(11, 61, 95, 0.08);
      --shadow-card: 0 4px 20px rgba(11, 61, 95, 0.06);
      --shadow-card-hover: 0 12px 32px rgba(11, 61, 95, 0.12);
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: var(--soft-gray);
      color: var(--text-dark);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    .serif-text {
      font-family: 'Noto Serif SC', 'STSong', 'Georgia', serif;
    }
    .container-main {
      margin-left: 240px;
      max-width: 1280px;
      padding-left: 40px;
      padding-right: 40px;
    }
    @media (max-width: 1024px) {
      .container-main {
        margin-left: 0;
        padding-left: 24px;
        padding-right: 24px;
      }
    }
    @media (max-width: 768px) {
      .container-main {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    .side-nav {
      width: 240px;
      background-color: var(--dark-abyss);
      height: 100vh;
      position: fixed;
      left: 0;
      top: 0;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      padding: 32px 0;
      z-index: 50;
      box-shadow: 2px 0 15px rgba(0,0,0,0.2);
      transition: transform 0.3s ease;
    }
    .nav-link {
      display: block;
      padding: 12px 24px;
      color: rgba(255,255,255,0.7);
      text-decoration: none;
      font-weight: 500;
      border-left: 3px solid transparent;
      transition: all 0.25s;
      font-size: 16px;
      letter-spacing: 0.5px;
    }
    .nav-link:hover, .nav-link.active {
      color: #fff;
      background-color: rgba(255,255,255,0.05);
      border-left-color: var(--coral-glow);
    }
    .social-icon {
      color: rgba(255,255,255,0.6);
      transition: color 0.2s;
      font-size: 20px;
      margin: 0 8px;
    }
    .social-icon:hover {
      color: var(--coral-glow);
    }
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 56px;
      background-color: var(--dark-abyss);
      align-items: center;
      justify-content: space-between;
      padding: 0 20px;
      z-index: 60;
    }
    @media (max-width: 1024px) {
      .side-nav {
        transform: translateX(-100%);
      }
      .side-nav.open {
        transform: translateX(0);
      }
      .mobile-header {
        display: flex;
      }
      .container-main {
        margin-left: 0;
        padding-top: 80px;
      }
    }
    .hamburger {
      display: flex;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 4px;
    }
    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: white;
      transition: 0.2s;
    }
    .card-hover {
      transition: all 0.3s ease;
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-card);
      border-radius: 12px;
      background: white;
    }
    .card-hover:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .btn-primary {
      background-color: var(--coral-glow);
      color: white;
      border-radius: 8px;
      padding: 14px 32px;
      font-weight: 600;
      display: inline-block;
      text-align: center;
      transition: all 0.25s;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      background-color: #E04A2E;
      transform: scale(1.03);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--deep-sea);
      color: var(--deep-sea);
      border-radius: 8px;
      padding: 14px 32px;
      font-weight: 600;
      display: inline-block;
      text-align: center;
      transition: all 0.25s;
    }
    .btn-outline:hover {
      background-color: var(--deep-sea);
      color: white;
    }
    .text-link {
      color: var(--coral-glow);
      text-decoration: underline;
      font-weight: 500;
      transition: all 0.2s;
    }
    .text-link:hover {
      color: #E04A2E;
      text-decoration: none;
    }
    .faq-item {
      border-radius: 8px;
      overflow: hidden;
      margin-bottom: 12px;
      background: white;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: white;
      transition: background 0.2s;
    }
    .faq-item:nth-child(even) .faq-question {
      background: #F0F7FA;
    }
    .faq-answer {
      padding: 0 24px 20px;
      color: #4a5568;
      display: none;
      line-height: 1.7;
    }
    .faq-item.open .faq-answer {
      display: block;
    }
    .faq-arrow {
      transition: transform 0.3s;
      font-size: 20px;
      color: var(--deep-sea);
    }
    .faq-item.open .faq-arrow {
      transform: rotate(180deg);
    }
    .fade-in-up {
      opacity: 0;
      transform: translateY(30px);
      transition: opacity 0.6s ease, transform 0.6s ease;
    }
    .fade-in-up.visible {
      opacity: 1;
      transform: translateY(0);
    }
    .whale-shadow {
      position: absolute;
      right: 10%;
      bottom: 10%;
      width: 300px;
      height: 200px;
      background: radial-gradient(ellipse at center, rgba(255,255,255,0.1) 0%, transparent 70%);
      border-radius: 50%;
      animation: float 6s ease-in-out infinite;
    }
    @keyframes float {
      0% { transform: translateY(0px); }
      50% { transform: translateY(-15px); }
      100% { transform: translateY(0px); }
    }
    .testimonial-scroll {
      display: flex;
      overflow-x: auto;
      gap: 24px;
      padding-bottom: 20px;
      scroll-snap-type: x mandatory;
    }
    .testimonial-scroll::-webkit-scrollbar {
      height: 4px;
    }
    .testimonial-scroll::-webkit-scrollbar-thumb {
      background: var(--deep-sea);
      border-radius: 4px;
    }
    .testimonial-card {
      min-width: 320px;
      scroll-snap-align: start;
    }
    @media (max-width: 768px) {
      .testimonial-card {
        min-width: 260px;
      }
    }