/* 基础变量 */
:root {
  --primary-color: #2F6BFF;
  --secondary-color: #6FA3FF;
  --button-gradient: linear-gradient(180deg, #4A8BFF 0%, #2F6BFF 100%);
  --card-bg: #FFFFFF;
  --background-color: #F4F7FB;
  --text-main-color: #1F2D3D;
  --text-black-color: #000000;
  --border-color: #D6E2FF;
  --glow-color: #A5C4FF;
}

/* Body background color from shared.css is var(--bg-color), assuming it's light for default text color */
.page-about {
  font-family: 'Arial', sans-serif;
  color: var(--text-main-color); /* Default text color for light background */
  line-height: 1.6;
  font-size: 16px;
}

.page-about__section {
  padding: 60px 0;
  position: relative;
}

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

.page-about__center-content {
  text-align: center;
}

.page-about__section-title {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 700;
  color: var(--text-black-color);
  text-align: center;
  margin-bottom: 40px;
  line-height: 1.2;
}

.page-about__section-title--light {
  color: #ffffff;
}

/* Hero Section */
.page-about__hero-section {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding-top: 10px; /* Small top padding, relying on body padding for header offset */
  padding-bottom: 60px;
  background-color: var(--primary-color);
  overflow: hidden;
}

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

.page-about__hero-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: brightness(0.4); /* Darken image for text readability */
}

.page-about__hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  text-align: center;
  color: #ffffff;
  padding: 40px 20px;
}

.page-about__main-title {
  font-size: clamp(32px, 5vw, 48px);
  font-weight: 800;
  margin-bottom: 20px;
  line-height: 1.2;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.page-about__hero-description {
  font-size: clamp(16px, 2vw, 20px);
  margin-bottom: 30px;
  opacity: 0.9;
}

/* Buttons */
.page-about__btn-primary,
.page-about__btn-secondary {
  display: inline-block;
  padding: 14px 30px;
  border-radius: 8px;
  font-size: 18px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.3s ease;
  max-width: 100%;
  box-sizing: border-box;
  white-space: normal;
  word-wrap: break-word;
}

.page-about__btn-primary {
  background: var(--button-gradient);
  color: #ffffff;
  border: none;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.page-about__btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.page-about__btn-secondary {
  background: #ffffff;
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
  margin-left: 15px;
}

.page-about__btn-secondary:hover {
  background: var(--primary-color);
  color: #ffffff;
  transform: translateY(-2px);
}

.page-about__cta-buttons {
  display: flex;
  justify-content: center;
  gap: 15px;
  margin-top: 30px;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow: hidden;
}

/* Content Flex Layout */
.page-about__content-flex {
  display: flex;
  align-items: center;
  gap: 40px;
  text-align: left;
}

.page-about__content-flex--reverse {
  flex-direction: row-reverse;
}

.page-about__text-block {
  flex: 1;
  min-width: 0; /* Ensures flex item can shrink */
}

.page-about__text-block p {
  margin-bottom: 20px;
  color: var(--text-main-color);
}

.page-about__text-block .page-about__btn-secondary {
  margin-top: 20px;
  margin-left: 0;
}

.page-about__image-block {
  flex: 1;
  display: flex;
  justify-content: center;
  align-items: center;
}

.page-about__image-block img {
  max-width: 100%;
  height: auto;
  border-radius: 10px;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.1);
  display: block;
}

/* Why Choose Us Section */
.page-about__light-bg {
  background-color: var(--background-color);
}

.page-about__reason-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 30px;
}

.page-about__card {
  background: var(--card-bg);
  border-radius: 12px;
  padding: 30px;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.08);
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  border: 1px solid var(--border-color);
  color: var(--text-main-color);
}

.page-about__card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.12);
}

.page-about__card img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin-bottom: 20px;
  display: block;
  margin-left: auto;
  margin-right: auto;
}

.page-about__card-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--primary-color);
  margin-bottom: 15px;
}

.page-about__card p {
  font-size: 15px;
  color: var(--text-main-color);
}

/* Values Section */
.page-about__dark-section {
  background-color: var(--primary-color);
  color: #ffffff;
}

.page-about__values-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
  margin-top: 40px;
}

.page-about__value-item {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 10px;
  padding: 25px;
  text-align: center;
  transition: background-color 0.3s ease;
}

.page-about__value-item:hover {
  background: rgba(255, 255, 255, 0.15);
}

.page-about__value-title {
  font-size: 20px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 10px;
}

.page-about__value-item p {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.9);
}

/* Join Community Section */
.page-about__join-description {
  font-size: clamp(16px, 2vw, 20px);
  margin-bottom: 40px;
  opacity: 0.9;
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.page-about__community-image {
  margin-top: 50px;
  border-radius: 12px;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

/* FAQ Section */
.page-about__faq-list {
  max-width: 900px;
  margin: 0 auto;
}

details.page-about__faq-item {
  margin-bottom: 15px;
  border-radius: 5px;
  border: 1px solid var(--border-color);
  overflow: hidden;
  background: var(--card-bg);
}

details.page-about__faq-item summary.page-about__faq-question {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 20px;
  cursor: pointer;
  user-select: none;
  list-style: none;
  transition: background-color 0.3s ease;
  color: var(--text-black-color);
}

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

details.page-about__faq-item summary.page-about__faq-question:hover {
  background: #f5f5f5;
}

.page-about__faq-qtext {
  flex: 1;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  text-align: left;
  color: var(--text-main-color);
}

.page-about__faq-toggle {
  font-size: 24px;
  font-weight: bold;
  color: var(--primary-color);
  flex-shrink: 0;
  margin-left: 15px;
  width: 28px;
  text-align: center;
}

details.page-about__faq-item .page-about__faq-answer {
  padding: 0 20px 20px;
  background: var(--background-color);
  border-radius: 0 0 5px 5px;
  color: var(--text-main-color);
}

.page-about__faq-answer p {
  margin-bottom: 0;
}

/* Universal image and container responsive styles */
.page-about img {
  max-width: 100%;
  height: auto;
  display: block;
}

.page-about__section,
.page-about__container,
.page-about__card,
.page-about__content-flex,
.page-about__reason-grid,
.page-about__values-grid,
.page-about__faq-list {
  max-width: 100%;
  width: 100%;
  box-sizing: border-box;
}

/* --- Media Queries --- */

/* Tablet/Small Desktop (max-width: 1024px) */
@media (max-width: 1024px) {
  .page-about__section {
    padding: 40px 0;
  }

  .page-about__section-title {
    margin-bottom: 30px;
  }

  .page-about__hero-content {
    padding: 30px 15px;
  }

  .page-about__main-title {
    font-size: clamp(30px, 4.5vw, 42px);
  }

  .page-about__hero-description {
    font-size: clamp(15px, 2vw, 18px);
  }

  .page-about__btn-primary,
  .page-about__btn-secondary {
    padding: 12px 25px;
    font-size: 16px;
  }

  .page-about__content-flex {
    flex-direction: column;
    gap: 30px;
  }

  .page-about__content-flex--reverse {
    flex-direction: column;
  }

  .page-about__reason-grid,
  .page-about__values-grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  }
}

/* Mobile (max-width: 768px) */
@media (max-width: 768px) {
  .page-about {
    font-size: 15px;
    line-height: 1.65;
  }

  .page-about__section {
    padding: 30px 0;
  }

  .page-about__container {
    padding: 0 15px;
  }

  .page-about__section-title {
    font-size: clamp(24px, 7vw, 32px);
    margin-bottom: 25px;
  }

  /* HERO 主图区域 */
  .page-about__hero-section {
    padding-top: 10px;
    padding-bottom: 40px;
  }

  .page-about__hero-image img {
    object-fit: contain !important; /* Prevent cropping on mobile */
    aspect-ratio: unset !important; /* Allow natural aspect ratio */
    filter: brightness(0.5); /* Slightly less dark for smaller screens */
  }

  .page-about__main-title {
    font-size: clamp(28px, 8vw, 38px);
    margin-bottom: 15px;
  }

  .page-about__hero-description {
    font-size: clamp(14px, 4vw, 16px);
    margin-bottom: 25px;
  }

  /* 按钮与按钮容器 */
  .page-about__btn-primary,
  .page-about__btn-secondary,
  .page-about a[class*="button"],
  .page-about a[class*="btn"] {
    max-width: 100% !important;
    width: 100% !important;
    box-sizing: border-box !important;
    white-space: normal !important;
    word-wrap: break-word !important;
    padding: 12px 20px;
    font-size: 16px;
    margin-left: 0 !important;
    margin-bottom: 10px; /* Space between stacked buttons */
  }

  .page-about__cta-buttons {
    flex-direction: column !important; /* Stack buttons vertically */
    gap: 0;
    padding: 0 15px;
  }

  .page-about__cta-buttons .page-about__btn-primary:last-child,
  .page-about__cta-buttons .page-about__btn-secondary:last-child {
    margin-bottom: 0;
  }

  /* 内容区通用图片和容器 */
  .page-about img {
    max-width: 100% !important;
    width: 100% !important;
    height: auto !important;
  }
  
  .page-about__section,
  .page-about__card,
  .page-about__container,
  .page-about__content-flex,
  .page-about__reason-grid,
  .page-about__values-grid,
  .page-about__faq-list {
    max-width: 100% !important;
    width: 100% !important;
    box-sizing: border-box !important;
    padding-left: 15px;
    padding-right: 15px;
  }

  /* 产品展示图区域 (Reason Grid for About page) */
  .page-about__reason-grid {
    grid-template-columns: 1fr;
    gap: 20px;
    overflow-x: hidden; /* Ensure no horizontal scroll */
  }
  
  .page-about__card {
    padding: 25px;
  }

  .page-about__card-title {
    font-size: 20px;
  }

  /* 装饰主标题 + 长文 SEO 区 (text-block, image-block) */
  .page-about__content-flex {
    flex-direction: column;
    gap: 20px;
  }

  .page-about__content-flex--reverse {
    flex-direction: column;
  }

  .page-about__text-block p {
    font-size: 15px;
    text-align: left;
  }

  .page-about__community-image {
    margin-top: 30px;
  }

  /* FAQ */
  details.page-about__faq-item summary.page-about__faq-question {
    padding: 15px;
  }
  .page-about__faq-qtext {
    font-size: 15px;
  }
  .page-about__faq-toggle {
    font-size: 20px;
    width: 24px;
    height: 24px;
  }
  details.page-about__faq-item .page-about__faq-answer {
    padding: 0 15px 15px;
  }
}