/* style/about.css */
/* 页面完整样式代码 - 注意：所有选择器必须使用BEM命名规则（双下划线__连接） */

/* 基础样式和颜色对比度 */
.page-about {
  font-family: Arial, sans-serif;
  line-height: 1.6;
  color: #ffffff; /* Body background is #000000 (dark), so text color is light */
  background-color: transparent; /* Main content background will be handled by sections */
}

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

.page-about__section {
  padding: 60px 0;
  text-align: center;
  position: relative;
  overflow: hidden; /* Ensure content doesn't overflow */
}

/* Hero Section */
.page-about__hero-section {
  position: relative;
  width: 100%;
  height: 600px; /* Fixed height for hero */
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  color: #ffffff;
  padding-top: var(--header-offset, 120px); /* Fixed header offset */
  box-sizing: border-box;
}

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

.page-about__hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.6); /* Dark overlay for text readability */
  z-index: 2;
}

.page-about__hero-content {
  position: relative;
  z-index: 3;
  max-width: 900px;
  padding: 20px;
  background: rgba(38, 169, 224, 0.2); /* Semi-transparent brand color */
  border-radius: 10px;
  backdrop-filter: blur(5px);
  -webkit-backdrop-filter: blur(5px);
}

.page-about__main-heading {
  font-size: 3.2em;
  margin-bottom: 20px;
  color: #ffffff;
  line-height: 1.2;
}

.page-about__intro-text {
  font-size: 1.2em;
  margin-bottom: 30px;
  color: #f0f0f0;
}

/* Section Titles */
.page-about__section-title {
  font-size: 2.5em;
  margin-bottom: 30px;
  color: #26A9E0; /* Brand color for titles */
  position: relative;
  padding-bottom: 10px;
}

.page-about__section-title::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: 0;
  transform: translateX(-50%);
  width: 80px;
  height: 4px;
  background-color: #26A9E0;
  border-radius: 2px;
}

.page-about__subsection-title {
  font-size: 1.8em;
  margin-top: 40px;
  margin-bottom: 20px;
  color: #ffffff; /* Default for dark sections */
}

/* Text Blocks */
.page-about__text-block {
  margin-bottom: 20px;
  font-size: 1.1em;
  color: #f0f0f0; /* Default for dark sections */
}

/* Lists */
.page-about__list {
  list-style: none;
  padding: 0;
  margin-bottom: 20px;
  text-align: left;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.page-about__list-item {
  margin-bottom: 10px;
  padding-left: 30px;
  position: relative;
  color: #f0f0f0; /* Default for dark sections */
}

.page-about__list-item::before {
  content: '✔';
  position: absolute;
  left: 0;
  color: #26A9E0;
  font-weight: bold;
}

.page-about__list--ordered {
  list-style: decimal;
  padding-left: 40px;
  text-align: left;
}

.page-about__list--ordered .page-about__list-item::before {
  content: none; /* Remove checkmark for ordered list */
}

/* Buttons */
.page-about__cta-buttons {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 20px;
  margin-top: 30px;
}

.page-about__btn-primary,
.page-about__btn-secondary {
  display: inline-block;
  padding: 15px 30px;
  border-radius: 8px;
  text-decoration: none;
  font-weight: bold;
  font-size: 1.1em;
  transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
  box-sizing: border-box;
  max-width: 100%; /* Ensure responsiveness */
  white-space: normal;
  word-wrap: break-word;
}

.page-about__btn-primary {
  background-color: #26A9E0; /* Brand color */
  color: #ffffff;
  border: 2px solid #26A9E0;
}

.page-about__btn-primary:hover {
  background-color: #1a7fb3;
  border-color: #1a7fb3;
}

.page-about__btn-secondary {
  background-color: transparent;
  color: #26A9E0;
  border: 2px solid #26A9E0;
}

.page-about__btn-secondary:hover {
  background-color: #26A9E0;
  color: #ffffff;
}

/* Image Styling */
.page-about__content-image {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin-top: 30px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
  display: block; /* Ensures proper spacing and max-width works */
  margin-left: auto;
  margin-right: auto;
}

/* Card Grid */
.page-about__card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
  margin-top: 40px;
}

.page-about__card {
  background: rgba(255, 255, 255, 0.1); /* Semi-transparent light background for cards on dark sections */
  padding: 25px;
  border-radius: 10px;
  text-align: center;
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.3);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  color: #ffffff; /* Light text for cards */
}

.page-about__card:hover {
  transform: translateY(-10px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.4);
}

.page-about__card-image {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin-bottom: 15px;
  display: block;
}

.page-about__card-title {
  font-size: 1.5em;
  margin-bottom: 10px;
  color: #26A9E0; /* Brand color for card titles */
}

.page-about__card-title a {
  color: #26A9E0;
  text-decoration: none;
}

.page-about__card-title a:hover {
  text-decoration: underline;
}

.page-about__card-description {
  font-size: 1em;
  color: #f0f0f0;
}

/* Section specific colors */
.page-about__light-bg {
  background-color: #ffffff;
}

.page-about__dark-bg {
  background-color: rgba(38, 169, 224, 0.1);
}

.page-about__light-bg .page-about__section-title,
.page-about__light-bg .page-about__subsection-title,
.page-about__light-bg .page-about__text-block,
.page-about__light-bg .page-about__list-item,
.page-about__light-bg .page-about__card-description {
  color: #333333; /* Dark text for light background sections */
}

.page-about__light-bg .page-about__list-item::before {
  color: #26A9E0;
}

.page-about__light-bg .page-about__card {
  background: #ffffff;
  color: #333333;
  box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.page-about__light-bg .page-about__card-title a {
  color: #26A9E0;
}

/* FAQ Section */
.page-about__faq {
  padding-bottom: 80px;
}

.page-about__faq-list {
  max-width: 900px;
  margin: 30px auto 0;
  text-align: left;
}

.page-about__faq-item {
  background: rgba(255, 255, 255, 0.1); /* Semi-transparent light background for FAQ items */
  border-radius: 8px;
  margin-bottom: 15px;
  overflow: hidden;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.page-about__light-bg .page-about__faq-item {
  background: #ffffff;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.page-about__faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px;
  font-size: 1.2em;
  font-weight: bold;
  cursor: pointer;
  color: #ffffff; /* Default for dark background */
  background: rgba(38, 169, 224, 0.1); /* Slightly lighter brand color for question background */
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  -webkit-touch-callout: none;
  -webkit-user-select: none;
  -moz-user-select: none;
  -ms-user-select: none;
  user-select: none;
}

.page-about__light-bg .page-about__faq-question {
  color: #333333;
  background: #f0f0f0;
  border-bottom: 1px solid #e0e0e0;
}

.page-about__faq-question::-webkit-details-marker {
  display: none;
}

.page-about__faq-question::marker {
  display: none;
}

.page-about__faq-toggle {
  font-size: 1.5em;
  line-height: 1;
  margin-left: 15px;
  color: #26A9E0;
}

.page-about__faq-answer {
  padding: 0 20px 20px;
  font-size: 1.1em;
  color: #f0f0f0; /* Default for dark background */
}

.page-about__light-bg .page-about__faq-answer {
  color: #333333;
}

.page-about__faq-answer p {
  margin: 0;
  padding-top: 15px;
}

/* details tag specific styles for native toggle behavior */
.page-about__faq-item[open] .page-about__faq-toggle {
  content: '−'; /* Change to minus when open */
}

/* Responsive Design */
@media (max-width: 1024px) {
  .page-about__main-heading {
    font-size: 2.5em;
  }
  .page-about__section-title {
    font-size: 2em;
  }
  .page-about__subsection-title {
    font-size: 1.5em;
  }
}

@media (max-width: 768px) {
  .page-about {
    font-size: 16px;
    line-height: 1.6;
  }

  .page-about__hero-section {
    height: 450px;
    padding-top: var(--header-offset, 120px) !important; /* Ensure mobile offset */
  }

  .page-about__main-heading {
    font-size: 2em;
  }

  .page-about__intro-text {
    font-size: 1em;
  }

  .page-about__section {
    padding: 40px 0;
  }

  .page-about__section-title {
    font-size: 1.8em;
    margin-bottom: 20px;
  }

  .page-about__subsection-title {
    font-size: 1.3em;
    margin-top: 30px;
    margin-bottom: 15px;
  }

  .page-about__text-block,
  .page-about__list-item,
  .page-about__card-description,
  .page-about__faq-answer {
    font-size: 1em;
  }

  .page-about__cta-buttons {
    flex-direction: column;
    gap: 15px;
    padding: 0 15px;
  }

  .page-about__btn-primary,
  .page-about__btn-secondary {
    width: 100% !important;
    max-width: 100% !important;
    padding: 12px 20px;
    font-size: 1em;
  }

  .page-about__card-grid {
    grid-template-columns: 1fr;
    padding: 0 15px;
  }

  .page-about__card {
    padding: 20px;
  }

  .page-about__card-title {
    font-size: 1.3em;
  }

  .page-about__faq-list {
    padding: 0 15px;
  }

  .page-about__faq-question {
    font-size: 1.1em;
    padding: 15px;
  }

  .page-about__faq-answer {
    padding: 0 15px 15px;
  }

  /* Mobile image/video responsiveness */
  .page-about img {
    max-width: 100% !important;
    width: 100% !important;
    height: auto !important;
    display: block !important;
  }

  .page-about video,
  .page-about__video {
    max-width: 100% !important;
    width: 100% !important;
    height: auto !important;
    display: block !important;
  }
  
  .page-about__section,
  .page-about__card,
  .page-about__container,
  .page-about__video-section,
  .page-about__video-container,
  .page-about__video-wrapper,
  .page-about__cta-buttons,
  .page-about__button-group,
  .page-about__btn-container,
  .page-about__faq-list {
    max-width: 100% !important;
    width: 100% !important;
    box-sizing: border-box !important;
    overflow: hidden !important;
  }
  
  /* Specific padding for mobile sections if needed to ensure content is not edge-to-edge */
  .page-about__section:not(.page-about__hero-section) .page-about__container {
    padding-left: 15px;
    padding-right: 15px;
  }
}

/* Ensure no filter is used on images */
.page-about img {
  filter: none !important;
}