:root {
      --page-win11vn-primary-color: #ffcc00; /* Vàng sáng */
      --page-win11vn-secondary-color: #333333; /* Xám đậm */
      --page-win11vn-accent-color: #ff3366; /* Hồng */
      --page-win11vn-background-dark: #1a1a1a;
      --page-win11vn-background-light: #2c2c2c;
      --page-win11vn-text-light: #ffffff;
      --page-win11vn-text-dark: #cccccc;
      --page-win11vn-border-radius: 8px;
      --page-win11vn-spacing-sm: 10px;
      --page-win11vn-spacing-md: 20px;
      --page-win11vn-spacing-lg: 40px;
    }

    .page-win11vn {
      font-family: 'Arial', sans-serif;
      color: var(--page-win11vn-text-light);
      background-color: var(--page-win11vn-background-dark);
      line-height: 1.6;
      padding-top: 10px; /* Adjusted for fixed header, as per instructions */
    }

    .page-win11vn__section {
      padding: var(--page-win11vn-spacing-lg) var(--page-win11vn-spacing-md);
      max-width: 1200px;
      margin: 0 auto;
      text-align: center;
    }

    .page-win11vn__section--dark {
      background-color: var(--page-win11vn-background-light);
    }

    .page-win11vn__section-title {
      font-size: 2.5em;
      color: var(--page-win11vn-primary-color);
      margin-bottom: var(--page-win11vn-spacing-lg);
      font-weight: bold;
      text-transform: uppercase;
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__section-subtitle {
      font-size: 1.2em;
      color: var(--page-win11vn-text-dark);
      margin-bottom: var(--page-win11vn-spacing-lg);
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    /* Hero Section */
    .page-win11vn__hero {
      background: linear-gradient(135deg, var(--page-win11vn-background-dark) 0%, #0a0a0a 100%);
      padding: calc(var(--page-win11vn-spacing-lg) * 2) var(--page-win11vn-spacing-md);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 60vh;
      text-align: center;
      position: relative;
    }

    .page-win11vn__hero-title {
      font-size: 3.5em;
      color: var(--page-win11vn-primary-color);
      margin-bottom: var(--page-win11vn-spacing-md);
      line-height: 1.2;
      font-weight: 900;
      text-shadow: 0 0 10px rgba(255, 204, 0, 0.7);
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__hero-description {
      font-size: 1.3em;
      color: var(--page-win11vn-text-light);
      max-width: 800px;
      margin-bottom: var(--page-win11vn-spacing-lg);
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__promo-link {
      display: inline-block;
      background-color: var(--page-win11vn-accent-color);
      color: var(--page-win11vn-text-light);
      padding: 15px 30px;
      border-radius: var(--page-win11vn-border-radius);
      text-decoration: none;
      font-weight: bold;
      font-size: 1.1em;
      transition: background-color 0.3s ease, transform 0.2s ease;
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__promo-link:hover {
      background-color: #e62e59;
      transform: translateY(-2px);
    }

    /* Floating Buttons */
    .page-win11vn__floating-buttons {
      position: fixed;
      bottom: var(--page-win11vn-spacing-md);
      right: var(--page-win11vn-spacing-md);
      display: flex;
      flex-direction: column;
      gap: var(--page-win11vn-spacing-sm);
      z-index: 1000;
    }

    .page-win11vn__floating-button {
      background-color: var(--page-win11vn-primary-color);
      color: var(--page-win11vn-secondary-color);
      padding: 12px 20px;
      border-radius: 50px;
      text-decoration: none;
      font-weight: bold;
      font-size: 1em;
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
      transition: background-color 0.3s ease, transform 0.2s ease;
      text-align: center;
      min-width: 100px;
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__floating-button--login {
      background-color: var(--page-win11vn-accent-color);
      color: var(--page-win11vn-text-light);
    }

    .page-win11vn__floating-button:hover {
      transform: translateY(-3px);
      opacity: 0.9;
    }

    /* Product Grid */
    .page-win11vn__product-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: var(--page-win11vn-spacing-md);
      margin-top: var(--page-win11vn-spacing-lg);
    }

    .page-win11vn__product-card {
      background-color: var(--page-win11vn-background-dark);
      border-radius: var(--page-win11vn-border-radius);
      overflow: hidden;
      box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      text-align: left;
      border: 1px solid var(--page-win11vn-secondary-color);
    }

    .page-win11vn__product-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 8px 16px rgba(0, 0, 0, 0.4);
    }

    .page-win11vn__product-image {
      width: 100%;
      max-width: 100%;
      height: 200px;
      object-fit: cover;
      display: block;
      border-bottom: 1px solid var(--page-win11vn-secondary-color);
    }

    .page-win11vn__product-content {
      padding: var(--page-win11vn-spacing-md);
    }

    .page-win11vn__product-title {
      font-size: 1.4em;
      color: var(--page-win11vn-primary-color);
      margin-bottom: var(--page-win11vn-spacing-sm);
      font-weight: bold;
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__product-description {
      font-size: 0.95em;
      color: var(--page-win11vn-text-dark);
      margin-bottom: var(--page-win11vn-spacing-md);
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__product-button {
      display: inline-block;
      background-color: var(--page-win11vn-accent-color);
      color: var(--page-win11vn-text-light);
      padding: 10px 15px;
      border-radius: var(--page-win11vn-border-radius);
      text-decoration: none;
      font-weight: bold;
      font-size: 0.9em;
      transition: background-color 0.3s ease;
      word-wrap: break-word;
      overflow-wrap: break-word;
      border: none;
      cursor: pointer;
    }

    .page-win11vn__product-button:hover {
      background-color: #e62e59;
    }

    /* Providers and Payments Grid */
    .page-win11vn__grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
      gap: var(--page-win11vn-spacing-md);
      margin-top: var(--page-win11vn-spacing-lg);
    }

    .page-win11vn__grid-item {
      background-color: var(--page-win11vn-background-dark);
      padding: var(--page-win11vn-spacing-md);
      border-radius: var(--page-win11vn-border-radius);
      box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 120px;
      border: 1px solid var(--page-win11vn-secondary-color);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      word-wrap: break-word;
      overflow-wrap: break-word;
      box-sizing: border-box; /* Crucial for list items */
    }

    .page-win11vn__grid-item:hover {
      transform: translateY(-3px);
      box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    }

    .page-win11vn__grid-image {
      max-width: 100px;
      height: auto;
      margin-bottom: var(--page-win11vn-spacing-sm);
      max-height: 80px;
    }

    .page-win11vn__grid-text {
      font-size: 1em;
      font-weight: bold;
      color: var(--page-win11vn-primary-color);
      text-align: center;
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    /* FAQ Section */
    .page-win11vn__faq-container {
      margin-top: var(--page-win11vn-spacing-lg);
      text-align: left;
    }

    .page-win11vn__faq-item {
      background-color: var(--page-win11vn-background-light);
      margin-bottom: var(--page-win11vn-spacing-sm);
      border-radius: var(--page-win11vn-border-radius);
      overflow: hidden;
      border: 1px solid var(--page-win11vn-secondary-color);
      box-sizing: border-box; /* Crucial for list items */
    }

    .page-win11vn__faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: var(--page-win11vn-spacing-md);
      background-color: var(--page-win11vn-background-dark);
      cursor: pointer;
      user-select: none;
      font-weight: bold;
      color: var(--page-win11vn-primary-color);
      transition: background-color 0.3s ease;
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__faq-question h3 {
      margin: 0;
      font-size: 1.1em;
      pointer-events: none; /* Prevent h3 from blocking click event */
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__faq-question:hover {
      background-color: #2a2a2a;
    }

    .page-win11vn__faq-toggle {
      font-size: 1.5em;
      line-height: 1;
      margin-left: var(--page-win11vn-spacing-sm);
      pointer-events: none; /* Prevent toggle icon from blocking click event */
    }

    .page-win11vn__faq-answer {
      max-height: 0;
      overflow: hidden;
      padding: 0 var(--page-win11vn-spacing-md);
      opacity: 0;
      transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1), padding 0.4s ease, opacity 0.4s ease;
      color: var(--page-win11vn-text-dark);
      word-wrap: break-word;
      overflow-wrap: break-word;
    }

    .page-win11vn__faq-item.active .page-win11vn__faq-answer {
      max-height: 2000px !important; /* Sufficiently large value */
      padding: var(--page-win11vn-spacing-md) !important;
      opacity: 1;
    }

    .page-win11vn__faq-item.active .page-win11vn__faq-toggle {
      content: '−';
    }

    /* Responsive Design */
    @media (max-width: 768px) {
      .page-win11vn__section {
        padding: var(--page-win11vn-spacing-lg) var(--page-win11vn-spacing-sm);
      }

      .page-win11vn__section-title {
        font-size: 2em;
      }

      .page-win11vn__hero {
        padding: var(--page-win11vn-spacing-lg) var(--page-win11vn-spacing-sm);
        min-height: 50vh;
      }

      .page-win11vn__hero-title {
        font-size: 2.5em;
      }

      .page-win11vn__hero-description {
        font-size: 1em;
      }

      .page-win11vn__promo-link {
        padding: 12px 25px;
        font-size: 1em;
      }

      .page-win11vn__floating-buttons {
        flex-direction: row;
        width: 100%;
        bottom: 0;
        right: 0;
        left: 0;
        justify-content: space-around;
        padding: var(--page-win11vn-spacing-sm);
        background-color: rgba(26, 26, 26, 0.9);
        box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.3);
      }

      .page-win11vn__floating-button {
        flex: 1;
        margin: 0 5px;
        padding: 10px 15px;
        font-size: 0.9em;
        min-width: unset;
      }

      .page-win11vn__product-grid {
        grid-template-columns: 1fr;
      }

      .page-win11vn__grid {
        grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
      }

      .page-win11vn__grid-item {
        width: 100% !important;
        max-width: 100% !important;
        box-sizing: border-box !important;
        margin-left: 0 !important;
        margin-right: 0 !important;
        padding: var(--page-win11vn-spacing-sm);
      }

      .page-win11vn__grid-text {
        font-size: 0.9em;
      }

      .page-win11vn__faq-question h3 {
        font-size: 1em;
      }

      .page-win11vn__faq-answer {
        padding: 0 var(--page-win11vn-spacing-sm);
      }

      .page-win11vn__faq-item.active .page-win11vn__faq-answer {
        padding: var(--page-win11vn-spacing-sm) !important;
      }
    }

    @media (max-width: 480px) {
      .page-win11vn__hero-title {
        font-size: 2em;
      }
      .page-win11vn__floating-button {
        font-size: 0.85em;
        padding: 8px 10px;
      }
      .page-win11vn__grid {
        grid-template-columns: repeat(2, 1fr); /* 2 columns on very small screens */
      }
    }

    /* Image responsiveness */
    .page-win11vn img {
      max-width: 100% !important;
      height: auto !important;
      box-sizing: border-box !important;
      word-wrap: break-word !important;
      overflow-wrap: break-word !important;
    }
    .page-win11vn__image-container {
      width: 100% !important;
      max-width: 100% !important;
      overflow: hidden !important;
      box-sizing: border-box !important;
    }