:root {
  --color-primary: #C91F17; /* Main */
  --color-secondary: #E53935; /* Auxiliary */
  --color-button-gradient-start: #FFD86A;
  --color-button-gradient-end: #E6B800;
  --color-card-bg: #D32F2F;
  --color-background-main: #B71C1C;
  --color-text-main: #FFF5E1;
  --color-border: #F2B544;
  --color-glow: #FFCC66;
  --color-gold: #F4D34D;
  --color-deep-red: #7A0E0E;

  /* Safe text colors for contrast */
  --color-text-dark: #333333;
  --color-text-light: #ffffff;
}

.page-app-di-dong {
  font-family: Arial, sans-serif;
  line-height: 1.6;
  color: var(--color-text-main); /* Default text color for sections with --color-background-main */
  background-color: var(--color-background-main);
}

.page-app-di-dong__content-area {
  max-width: 1170px;
  margin: 0 auto;
  padding: 40px 16px;
  box-sizing: border-box;
}

.page-app-di-dong__content-area--center {
  text-align: center;
}

.page-app-di-dong__section-title {
  font-size: 2.5em;
  margin-bottom: 20px;
  text-align: center;
  font-weight: bold;
  color: var(--color-text-light); /* Default for sections with dark backgrounds */
  line-height: 1.2;
}

.page-app-di-dong__text-block {
  font-size: 1.1em;
  margin-bottom: 20px;
  text-align: center;
}

/* Buttons */
.page-app-di-dong__btn-primary,
.page-app-di-dong__btn-secondary {
  display: inline-block;
  padding: 14px 28px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  transition: background-color 0.3s ease, transform 0.2s ease;
  cursor: pointer;
  white-space: normal;
  word-wrap: break-word;
  max-width: 100%;
  box-sizing: border-box;
  text-align: center;
}

.page-app-di-dong__btn-primary {
  background: linear-gradient(180deg, var(--color-button-gradient-start) 0%, var(--color-button-gradient-end) 100%);
  color: var(--color-text-dark); /* Ensure contrast on gold button */
  border: none;
}

.page-app-di-dong__btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.page-app-di-dong__btn-secondary {
  background: transparent;
  color: var(--color-gold);
  border: 2px solid var(--color-gold);
}

.page-app-di-dong__btn-secondary:hover {
  background: var(--color-gold);
  color: var(--color-text-dark);
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

/* Image common styles */
.page-app-di-dong img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* HERO Section */
.page-app-di-dong__hero-section {
  padding-top: 10px; /* Rely on body padding for header offset */
  padding-bottom: 60px;
  background-color: var(--color-background-main);
  color: var(--color-text-main);
}

.page-app-di-dong__hero-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  padding: 40px 16px;
  gap: 40px;
}

.page-app-di-dong__hero-content {
  flex: 1 1 50%;
  min-width: 300px;
}

.page-app-di-dong__main-title {
  font-size: clamp(2.2em, 5vw, 2.8em); /* Smaller base size, responsive */
  margin-bottom: 20px;
  font-weight: bold;
  line-height: 1.2;
  color: var(--color-text-main);
}

.page-app-di-dong__description {
  font-size: 1.2em;
  margin-bottom: 30px;
  color: var(--color-text-main);
}

.page-app-di-dong__cta-buttons {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  justify-content: flex-start;
}

.page-app-di-dong__hero-image {
  flex: 1 1 40%;
  text-align: center;
}

.page-app-di-dong__hero-side-image {
  max-width: 600px;
  width: 100%;
  height: auto;
  border-radius: 10px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

/* Intro Section (3-column features) */
.page-app-di-dong__intro-section {
  background-color: var(--color-text-light); /* Light background for contrast */
  color: var(--color-text-dark);
  padding: 60px 0;
}

.page-app-di-dong__intro-section .page-app-di-dong__section-title {
  color: var(--color-text-dark);
}

.page-app-di-dong__intro-section .page-app-di-dong__text-block {
  color: var(--color-text-dark);
}

.page-app-di-dong__features-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 30px;
  justify-content: center;
  margin-top: 40px;
}

.page-app-di-dong__feature-item {
  flex: 1 1 30%;
  min-width: 280px;
  text-align: center;
  padding: 20px;
  border-radius: 10px;
  background-color: #fff;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.08);
  transition: transform 0.3s ease;
}

.page-app-di-dong__feature-item:hover {
  transform: translateY(-5px);
}

.page-app-di-dong__icon-box-media {
  width: 240px;
  height: 240px;
  aspect-ratio: 1/1;
  margin: 0 auto 20px;
  border-radius: 50%;
  overflow: hidden;
  border: 4px solid var(--color-gold);
  box-shadow: 0 0 15px rgba(244, 211, 77, 0.5);
}

.page-app-di-dong__icon-box-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 50%;
  display: block;
}

.page-app-di-dong__feature-title {
  font-size: 1.8em;
  margin-bottom: 10px;
  color: var(--color-primary);
}

.page-app-di-dong__feature-description {
  font-size: 1em;
  color: var(--color-text-dark);
}

/* Download Guide Section */
.page-app-di-dong__download-guide-section {
  background-color: #f8f8f8; /* Light background */
  color: var(--color-text-dark);
  padding: 60px 0;
}

.page-app-di-dong__download-guide-section .page-app-di-dong__section-title {
  color: var(--color-text-dark);
}

.page-app-di-dong__download-guide-section .page-app-di-dong__text-block {
  color: var(--color-text-dark);
}

.page-app-di-dong__guide-steps {
  margin-top: 40px;
}

.page-app-di-dong__guide-step-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 60px;
}

.page-app-di-dong__guide-step-item:last-child {
  margin-bottom: 0;
}

.page-app-di-dong__step-title {
  font-size: 2em;
  color: var(--color-primary);
  margin-bottom: 15px;
  text-align: center;
}

.page-app-di-dong__guide-step-item p {
  font-size: 1.1em;
  text-align: center;
  max-width: 800px;
  margin-bottom: 25px;
  color: var(--color-text-dark);
}

.page-app-di-dong__guide-image {
  max-width: 800px;
  width: 100%;
  height: auto;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
}

.page-app-di-dong__cta-bottom {
  text-align: center;
  margin-top: 40px;
}

/* App Features Section */
.page-app-di-dong__app-features-section {
  background-color: var(--color-card-bg); /* Darker red background */
  color: var(--color-text-main);
  padding: 60px 0;
}

.page-app-di-dong__app-features-section .page-app-di-dong__section-title {
  color: var(--color-text-main);
}

.page-app-di-dong__app-features-section .page-app-di-dong__text-block {
  color: var(--color-text-main);
}

.page-app-di-dong__feature-list {
  list-style: none;
  padding: 0;
  margin: 30px auto;
  max-width: 800px;
  text-align: left;
  font-size: 1.1em;
}

.page-app-di-dong__feature-list li {
  margin-bottom: 15px;
  padding-left: 30px;
  position: relative;
  color: var(--color-text-main);
}

.page-app-di-dong__feature-list li::before {
  content: '✔️'; /* Checkmark icon */
  position: absolute;
  left: 0;
  color: var(--color-gold);
  font-weight: bold;
}

.page-app-di-dong__main-content-image {
  margin: 40px auto 0;
  border-radius: 10px;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

/* FAQ Section */
.page-app-di-dong__faq-section {
  background-color: var(--color-text-light); /* Light background */
  color: var(--color-text-dark);
  padding: 60px 0;
}

.page-app-di-dong__faq-section .page-app-di-dong__section-title {
  color: var(--color-text-dark);
}

.page-app-di-dong__faq-list {
  margin-top: 40px;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.page-app-di-dong__faq-item {
  background-color: #fff;
  border: 1px solid #e0e0e0;
  border-radius: 8px;
  margin-bottom: 15px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.page-app-di-dong__faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 25px;
  font-size: 1.2em;
  font-weight: bold;
  color: var(--color-primary);
  cursor: pointer;
  background-color: #f9f9f9;
  border-bottom: 1px solid #e0e0e0;
  list-style: none; /* For details/summary */
}

.page-app-di-dong__faq-question::-webkit-details-marker {
  display: none;
}

.page-app-di-dong__faq-toggle {
  font-size: 1.5em;
  line-height: 1;
  transition: transform 0.3s ease;
}

.page-app-di-dong__faq-item[open] .page-app-di-dong__faq-toggle {
  transform: rotate(45deg);
}

.page-app-di-dong__faq-answer {
  padding: 15px 25px 20px;
  font-size: 1.1em;
  color: var(--color-text-dark);
}

/* Final CTA Section */
.page-app-di-dong__cta-final-section {
  background-color: var(--color-background-main);
  color: var(--color-text-main);
  padding: 80px 0;
}

.page-app-di-dong__cta-final-section .page-app-di-dong__section-title {
  color: var(--color-text-main);
}

.page-app-di-dong__cta-final-section .page-app-di-dong__text-block {
  color: var(--color-text-main);
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

/* Responsive Styles */
@media (max-width: 1024px) {
  .page-app-di-dong__main-title {
    font-size: clamp(2em, 4.5vw, 2.5em);
  }
  .page-app-di-dong__section-title {
    font-size: 2em;
  }
  .page-app-di-dong__hero-container {
    padding: 30px 16px;
    gap: 30px;
  }
  .page-app-di-dong__features-grid {
    gap: 20px;
  }
  .page-app-di-dong__feature-item {
    min-width: 250px;
  }
  .page-app-di-dong__icon-box-media {
    width: 200px;
    height: 200px;
  }
}

@media (max-width: 768px) {
  /* General mobile settings */
  .page-app-di-dong {
    font-size: 16px;
    line-height: 1.6;
  }
  .page-app-di-dong__content-area,
  .page-app-di-dong__hero-container {
    padding: 20px 15px !important;
  }

  /* HERO Section */
  .page-app-di-dong__hero-section {
    padding-top: 10px !important; /* Rely on body padding */
    padding-bottom: 40px !important;
  }
  .page-app-di-dong__hero-container {
    flex-direction: column;
    text-align: center;
    gap: 20px;
  }
  .page-app-di-dong__hero-content {
    flex: 1 1 100%;
    min-width: unset;
  }
  .page-app-di-dong__main-title {
    font-size: 1.8em !important; 
    margin-bottom: 15px;
  }
  .page-app-di-dong__description {
    font-size: 1em;
    margin-bottom: 20px;
  }
  .page-app-di-dong__cta-buttons {
    flex-direction: column;
    gap: 15px;
    width: 100%;
    max-width: 100%;
    box-sizing: border-box;
    padding-left: 15px;
    padding-right: 15px;
  }
  .page-app-di-dong__btn-primary,
  .page-app-di-dong__btn-secondary {
    max-width: 100% !important;
    width: 100% !important;
    box-sizing: border-box !important;
    white-space: normal !important;
    word-wrap: break-word !important;
    padding: 12px 15px;
  }
  .page-app-di-dong__hero-image {
    flex: 1 1 100%;
  }
  .page-app-di-dong__hero-side-image {
    max-width: 90%; /* Adjust for smaller screens */
  }

  /* Intro Section (3-column features) */
  .page-app-di-dong__intro-section {
    padding: 40px 0 !important;
  }
  .page-app-di-dong__section-title {
    font-size: 1.8em !important;
  }
  .page-app-di-dong__features-grid {
    flex-direction: column;
    gap: 20px;
  }
  .page-app-di-dong__feature-item {
    min-width: unset;
    flex: 1 1 100%;
  }
  .page-app-di-dong__icon-box-media {
    width: 180px;
    height: 180px;
    margin-bottom: 15px;
  }
  .page-app-di-dong__feature-title {
    font-size: 1.5em;
  }

  /* Download Guide Section */
  .page-app-di-dong__download-guide-section {
    padding: 40px 0 !important;
  }
  .page-app-di-dong__guide-step-item {
    margin-bottom: 40px;
  }
  .page-app-di-dong__step-title {
    font-size: 1.6em;
  }
  .page-app-di-dong__guide-step-item p {
    font-size: 1em;
    padding: 0 10px;
  }
  .page-app-di-dong__guide-image,
  .page-app-di-dong__main-content-image {
    max-width: 100% !important;
    width: 100% !important;
    height: auto !important;
  }
  .page-app-di-dong__cta-bottom {
    padding-left: 15px;
    padding-right: 15px;
  }

  /* App Features Section */
  .page-app-di-dong__app-features-section {
    padding: 40px 0 !important;
  }
  .page-app-di-dong__feature-list {
    font-size: 1em;
    margin: 20px auto;
    padding: 0 15px;
  }
  .page-app-di-dong__feature-list li {
    padding-left: 25px;
  }

  /* FAQ Section */
  .page-app-di-dong__faq-section {
    padding: 40px 0 !important;
  }
  .page-app-di-dong__faq-question {
    padding: 15px 20px;
    font-size: 1.1em;
  }
  .page-app-di-dong__faq-answer {
    padding: 10px 20px 15px;
    font-size: 1em;
  }

  /* Final CTA Section */
  .page-app-di-dong__cta-final-section {
    padding: 60px 0 !important;
  }
  .page-app-di-dong__cta-final-section .page-app-di-dong__text-block {
    padding-left: 15px;
    padding-right: 15px;
  }

  /* Generic image and container responsiveness for mobile */
  .page-app-di-dong img {
    max-width: 100% !important;
    width: 100% !important;
    height: auto !important;
  }
  .page-app-di-dong__section,
  .page-app-di-dong__card,
  .page-app-di-dong__container,
  .page-app-di-dong__content-area {
    max-width: 100% !important;
    width: 100% !important;
    box-sizing: border-box !important;
    padding-left: 15px;
    padding-right: 15px;
  }
}