/* Tổng quan */
    .page-sumvipopen {
      font-family: 'Arial', sans-serif;
      color: #333;
      line-height: 1.6;
      background-color: #f9f9f9;
      margin: 0;
      padding: 0;
      overflow-x: hidden;
    }

    .page-sumvipopen__container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 20px;
      box-sizing: border-box;
    }

    /* Hero Section */
    .page-sumvipopen__hero-section {
      position: relative;
      width: 100%;
      min-height: 400px;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      color: #fff;
      padding-top: 10px; /* Adjust for fixed header */
      box-sizing: border-box;
      overflow: hidden;
    }

    .page-sumvipopen__hero-image {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      object-fit: cover;
      z-index: 1;
    }

    .page-sumvipopen__hero-overlay {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(0, 0, 0, 0.6);
      z-index: 2;
    }

    .page-sumvipopen__hero-content {
      position: relative;
      z-index: 3;
      max-width: 900px;
      padding: 20px;
    }

    .page-sumvipopen__hero-title {
      font-size: 3em;
      margin-bottom: 15px;
      line-height: 1.2;
      color: #FFD700; /* Gold color for emphasis */
      text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.7);
    }

    .page-sumvipopen__hero-description {
      font-size: 1.3em;
      margin-bottom: 30px;
      max-width: 700px;
      margin-left: auto;
      margin-right: auto;
      color: #eee;
    }

    .page-sumvipopen__download-button {
      display: inline-block;
      background-color: #007bff;
      color: #fff;
      padding: 15px 30px;
      border-radius: 8px;
      font-size: 1.2em;
      font-weight: bold;
      text-decoration: none;
      transition: background-color 0.3s ease, transform 0.2s ease;
      cursor: pointer;
      border: none;
    }

    .page-sumvipopen__download-button:hover {
      background-color: #0056b3;
      transform: translateY(-2px);
    }

    /* General Section Styling */
    .page-sumvipopen__section {
      padding: 60px 0;
      background-color: #fff;
      margin-bottom: 20px;
      border-radius: 8px;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    }

    .page-sumvipopen__section--grey {
      background-color: #f0f2f5;
    }

    .page-sumvipopen__section-title {
      font-size: 2.5em;
      color: #007bff;
      text-align: center;
      margin-bottom: 40px;
      position: relative;
      padding-bottom: 15px;
    }

    .page-sumvipopen__section-title::after {
      content: '';
      position: absolute;
      left: 50%;
      bottom: 0;
      transform: translateX(-50%);
      width: 80px;
      height: 4px;
      background-color: #FFD700;
      border-radius: 2px;
    }

    .page-sumvipopen__content-block {
      margin-bottom: 30px;
      text-align: justify;
    }

    .page-sumvipopen__content-block h3 {
      font-size: 1.8em;
      color: #333;
      margin-bottom: 15px;
      text-align: left;
    }

    .page-sumvipopen__content-block p {
      margin-bottom: 15px;
      font-size: 1.1em;
      color: #555;
    }

    .page-sumvipopen__image-wrapper {
      text-align: center;
      margin: 30px 0;
    }

    .page-sumvipopen__image {
      max-width: 100%;
      height: auto;
      border-radius: 8px;
      box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    }

    /* Step List */
    .page-sumvipopen__step-list {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 30px;
      list-style: none;
      padding: 0;
      margin: 0;
    }

    .page-sumvipopen__step-item {
      background-color: #fff;
      border: 1px solid #ddd;
      border-radius: 10px;
      padding: 30px;
      text-align: center;
      flex: 1 1 calc(33% - 40px); /* 3 items per row */
      max-width: calc(33% - 40px);
      box-shadow: 0 4px 10px rgba(0, 0, 0, 0.08);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      box-sizing: border-box;
    }

    .page-sumvipopen__step-item:hover {
      transform: translateY(-5px);
      box-shadow: 0 6px 15px rgba(0, 0, 0, 0.12);
    }

    .page-sumvipopen__step-number {
      font-size: 2.5em;
      color: #007bff;
      font-weight: bold;
      margin-bottom: 15px;
    }

    .page-sumvipopen__step-title {
      font-size: 1.5em;
      color: #333;
      margin-bottom: 15px;
    }

    .page-sumvipopen__step-description {
      font-size: 1em;
      color: #666;
    }

    /* Game Grid */
    .page-sumvipopen__game-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 30px;
      padding: 0;
      margin: 0;
      list-style: none;
    }

    .page-sumvipopen__game-card {
      background-color: #fff;
      border-radius: 10px;
      overflow: hidden;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      box-sizing: border-box;
      display: flex;
      flex-direction: column;
      text-align: center;
    }

    .page-sumvipopen__game-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    }

    .page-sumvipopen__game-image {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }

    .page-sumvipopen__game-content {
      padding: 20px;
      flex-grow: 1;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .page-sumvipopen__game-title {
      font-size: 1.4em;
      color: #007bff;
      margin-bottom: 10px;
      font-weight: bold;
    }

    .page-sumvipopen__game-description {
      font-size: 0.95em;
      color: #666;
      margin-bottom: 15px;
    }

    /* Promotion Card */
    .page-sumvipopen__promotion-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
      gap: 30px;
      padding: 0;
      margin: 0;
      list-style: none;
    }

    .page-sumvipopen__promotion-card {
      background-color: #fff;
      border-radius: 10px;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
      overflow: hidden;
      display: flex;
      flex-direction: column;
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      box-sizing: border-box;
    }

    .page-sumvipopen__promotion-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
    }

    .page-sumvipopen__promotion-image {
      width: 100%;
      height: 220px;
      object-fit: cover;
    }

    .page-sumvipopen__promotion-content {
      padding: 25px;
      flex-grow: 1;
    }

    .page-sumvipopen__promotion-title {
      font-size: 1.5em;
      color: #E65100; /* Orange for promotions */
      margin-bottom: 15px;
      font-weight: bold;
    }

    .page-sumvipopen__promotion-description {
      font-size: 1.05em;
      color: #555;
      margin-bottom: 20px;
    }

    /* Advantage List */
    .page-sumvipopen__advantage-list {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
      gap: 25px;
      list-style: none;
      padding: 0;
      margin: 0;
    }

    .page-sumvipopen__advantage-item {
      background-color: #fff;
      border-left: 5px solid #007bff;
      padding: 25px;
      border-radius: 8px;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
      transition: border-color 0.3s ease, transform 0.3s ease;
      box-sizing: border-box;
    }

    .page-sumvipopen__advantage-item:hover {
      border-color: #FFD700;
      transform: translateY(-3px);
    }

    .page-sumvipopen__advantage-item h4 {
      font-size: 1.3em;
      color: #007bff;
      margin-bottom: 10px;
    }

    .page-sumvipopen__advantage-item p {
      font-size: 1em;
      color: #666;
    }

    /* FAQ Section */
    .page-sumvipopen__faq-section {
      padding: 60px 0;
      background-color: #f0f2f5;
      margin-bottom: 20px;
      border-radius: 8px;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    }

    .page-sumvipopen__faq-item {
      background-color: #fff;
      border-radius: 8px;
      margin-bottom: 15px;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
      overflow: hidden;
      box-sizing: border-box;
    }

    .page-sumvipopen__faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 20px 25px;
      font-size: 1.2em;
      font-weight: bold;
      color: #333;
      cursor: pointer;
      user-select: none;
      transition: background-color 0.3s ease;
      border-bottom: 1px solid #eee;
    }

    .page-sumvipopen__faq-question h3 {
      margin: 0;
      font-size: 1.2em;
      color: #333;
      pointer-events: none; /* Prevent h3 from blocking click event */
    }

    .page-sumvipopen__faq-question:hover {
      background-color: #f5f5f5;
    }

    .page-sumvipopen__faq-toggle {
      font-size: 1.5em;
      line-height: 1;
      margin-left: 15px;
      pointer-events: none; /* Prevent toggle from blocking click event */
      color: #007bff;
      transition: transform 0.3s ease;
    }

    .page-sumvipopen__faq-item.active .page-sumvipopen__faq-toggle {
      transform: rotate(45deg);
    }

    .page-sumvipopen__faq-answer {
      max-height: 0;
      overflow: hidden;
      padding: 0 25px;
      opacity: 0;
      transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1), padding 0.4s ease, opacity 0.4s ease;
      color: #555;
      font-size: 1.05em;
    }

    .page-sumvipopen__faq-item.active .page-sumvipopen__faq-answer {
      max-height: 2000px !important; /* Sufficiently large value */
      padding: 20px 25px !important;
      opacity: 1;
    }

    .page-sumvipopen__faq-answer p {
      margin: 0;
      padding-bottom: 10px;
    }
    .page-sumvipopen__faq-answer p:last-child {
      padding-bottom: 0;
    }

    /* Call to Action */
    .page-sumvipopen__call-to-action {
      text-align: center;
      padding: 50px 20px;
      background-color: #007bff;
      color: #fff;
      border-radius: 8px;
      margin-bottom: 20px;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    }

    .page-sumvipopen__call-to-action h2 {
      font-size: 2.5em;
      margin-bottom: 20px;
      color: #FFD700;
    }

    .page-sumvipopen__call-to-action p {
      font-size: 1.3em;
      margin-bottom: 30px;
      max-width: 800px;
      margin-left: auto;
      margin-right: auto;
    }

    /* Floating Promotion Button */
    .page-sumvipopen__floating-button {
      position: fixed;
      bottom: 20px;
      right: 20px;
      background-color: #E65100; /* Orange for high visibility */
      color: #fff;
      padding: 15px 25px;
      border-radius: 50px;
      font-size: 1.1em;
      font-weight: bold;
      text-decoration: none;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
      z-index: 1000;
      transition: background-color 0.3s ease, transform 0.2s ease;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      cursor: pointer;
      border: none;
    }

    .page-sumvipopen__floating-button:hover {
      background-color: #BF360C;
      transform: translateY(-3px);
    }

    /* Responsive Design */
    @media (max-width: 1024px) {
      .page-sumvipopen__hero-title {
        font-size: 2.5em;
      }
      .page-sumvipopen__hero-description {
        font-size: 1.1em;
      }
      .page-sumvipopen__section-title {
        font-size: 2em;
      }
      .page-sumvipopen__step-item {
        flex: 1 1 calc(50% - 30px); /* 2 items per row */
        max-width: calc(50% - 30px);
      }
    }

    @media (max-width: 768px) {
      .page-sumvipopen__container {
        padding: 15px;
      }
      .page-sumvipopen__hero-section {
        min-height: 300px;
        padding-top: 10px !important; /* Ensure spacing for fixed header */
      }
      .page-sumvipopen__hero-title {
        font-size: 2em;
      }
      .page-sumvipopen__hero-description {
        font-size: 1em;
      }
      .page-sumvipopen__download-button {
        padding: 12px 25px;
        font-size: 1.1em;
      }
      .page-sumvipopen__section {
        padding: 40px 0;
      }
      .page-sumvipopen__section-title {
        font-size: 1.8em;
        margin-bottom: 30px;
      }
      .page-sumvipopen__content-block h3 {
        font-size: 1.5em;
      }
      .page-sumvipopen__content-block p {
        font-size: 1em;
      }

      /* List item responsive override */
      .page-sumvipopen__step-list,
      .page-sumvipopen__game-grid,
      .page-sumvipopen__promotion-grid,
      .page-sumvipopen__advantage-list {
        display: flex;
        flex-direction: column;
        gap: 20px;
        width: 100% !important;
        max-width: 100% !important;
        padding: 0 !important;
        margin-left: 0 !important;
        margin-right: 0 !important;
        box-sizing: border-box !important;
      }

      .page-sumvipopen__step-item,
      .page-sumvipopen__game-card,
      .page-sumvipopen__promotion-card,
      .page-sumvipopen__advantage-item {
        width: 100% !important;
        max-width: 100% !important;
        margin-left: 0 !important;
        margin-right: 0 !important;
        padding: 20px !important;
        box-sizing: border-box !important;
        word-wrap: break-word !important;
        overflow-wrap: break-word !important;
        word-break: break-word !important;
      }

      .page-sumvipopen__image,
      .page-sumvipopen__game-image,
      .page-sumvipopen__promotion-image {
        max-width: 100% !important;
        height: auto !important;
        box-sizing: border-box !important;
      }

      .page-sumvipopen__faq-question {
        padding: 15px 20px;
        font-size: 1.1em;
      }
      .page-sumvipopen__faq-question h3 {
        font-size: 1.1em;
      }
      .page-sumvipopen__faq-answer {
        padding: 0 20px;
        font-size: 1em;
      }
      .page-sumvipopen__faq-item.active .page-sumvipopen__faq-answer {
        padding: 15px 20px !important;
      }

      .page-sumvipopen__call-to-action h2 {
        font-size: 2em;
      }
      .page-sumvipopen__call-to-action p {
        font-size: 1.1em;
      }
      .page-sumvipopen__floating-button {
        bottom: 15px;
        right: 15px;
        padding: 12px 20px;
        font-size: 1em;
      }
    }

    @media (max-width: 480px) {
      .page-sumvipopen__hero-title {
        font-size: 1.8em;
      }
      .page-sumvipopen__hero-description {
        font-size: 0.9em;
      }
      .page-sumvipopen__section-title {
        font-size: 1.6em;
      }
      .page-sumvipopen__content-block h3 {
        font-size: 1.3em;
      }
      .page-sumvipopen__faq-question {
        font-size: 1em;
      }
      .page-sumvipopen__faq-question h3 {
        font-size: 1em;
      }
    }