/* =============================================
   页面专属 CSS — about（品牌介绍）
   作用域：.page-about
   移动端优先 + 桌面增强
   ============================================= */

/* ---------- 作用域容器 ---------- */
.page-about {
  --about-hero-gap: 2rem;
  --about-section-gap: 3rem;
  --about-card-radius: 8px;
  --about-clip-offset: 16px;
  --about-max-width: 1120px;
  color: var(--color-text);
  background: var(--color-bg);
  font-family: var(--font-body);
  line-height: 1.6;
  padding: 1.25rem 1rem 3rem;
  position: relative;
}

/* ---------- 面包屑 ---------- */
.page-about__breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-border);
  max-width: var(--about-max-width);
  margin-left: auto;
  margin-right: auto;
}

.page-about__breadcrumb-link {
  color: var(--color-gold-light);
  text-decoration: none;
  transition: color var(--transition-speed);
}

.page-about__breadcrumb-link:hover,
.page-about__breadcrumb-link:focus-visible {
  color: var(--color-gold);
  outline: 2px solid var(--color-gold);
  outline-offset: 2px;
}

.page-about__breadcrumb-sep {
  color: var(--color-border);
}

.page-about__breadcrumb-current {
  color: var(--color-text);
}

/* ---------- 首屏 Hero ---------- */
.page-about__hero {
  display: flex;
  flex-direction: column;
  gap: var(--about-hero-gap);
  max-width: var(--about-max-width);
  margin: 0 auto 3rem;
  position: relative;
}

.page-about__hero-text {
  order: 2;
}

.page-about__hero-title {
  font-family: var(--font-heading);
  font-size: 3.25rem;
  font-weight: 700;
  line-height: 1.1;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin: 0 0 1rem;
  letter-spacing: 0.04em;
}

.page-about__hero-desc {
  font-size: 1rem;
  color: var(--color-text-muted);
  max-width: 36em;
  margin: 0 0 1.5rem;
}

.page-about__hero-link {
  display: inline-block;
  font-size: 0.9375rem;
  color: var(--color-gold-light);
  text-decoration: none;
  border-bottom: 2px solid transparent;
  transition: border-color var(--transition-speed), color var(--transition-speed);
  padding-bottom: 2px;
}

.page-about__hero-link:hover,
.page-about__hero-link:focus-visible {
  border-bottom-color: var(--color-gold);
  color: var(--color-gold);
  outline: none;
}

.page-about__hero-image {
  order: 1;
  width: 100%;
  max-width: 500px;
  margin: 0 auto;
}

.page-about__img-hero {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: var(--about-card-radius);
  clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--about-clip-offset)), calc(100% - var(--about-clip-offset)) 100%, 0 100%);
  box-shadow: var(--shadow-gold);
}

/* ---------- 章节通用 ---------- */
.page-about__section {
  max-width: var(--about-max-width);
  margin: 0 auto var(--about-section-gap);
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
  position: relative;
}

.page-about__section--alt {
  /* 交替视觉：通过内边距或背景微差区分 */
}

.page-about__section--last {
  margin-bottom: 0;
}

.page-about__section-header {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: 1.75rem;
}

.page-about__section-number {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 700;
  line-height: 1;
  background: var(--gradient-gold);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  flex-shrink: 0;
}

.page-about__section-title {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-text);
  margin: 0;
  line-height: 1.2;
}

.page-about__section-body {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.page-about__section-body--centered {
  align-items: center;
}

.page-about__section-figure {
  width: 100%;
  max-width: 300px;
  margin: 0 auto;
}

.page-about__img-small {
  display: block;
  width: 100%;
  height: auto;
  max-width: 100%;
  object-fit: cover;
  border-radius: 6px;
  clip-path: polygon(0 0, calc(100% - 10px) 0, 100% 10px, 100% 100%, 0 100%);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
}

/* ---------- 品牌理念卡片 ---------- */
.page-about__card--philosophy {
  background: var(--color-surface);
  border: 2px solid transparent;
  border-image: var(--gradient-gold) 1;
  border-radius: var(--about-card-radius);
  padding: 1.5rem;
  position: relative;
  transition: transform var(--transition-speed), box-shadow var(--transition-speed);
}

.page-about__card--philosophy:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-gold);
}

.page-about__card-text {
  font-size: 1rem;
  color: var(--color-text);
  margin: 0 0 1.5rem;
}

.page-about__highlight {
  color: var(--color-gold-light);
  font-weight: 600;
}

/* 原则列表 */
.page-about__principle-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.page-about__principle-item {
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
}

.page-about__principle-icon {
  color: var(--color-gold);
  font-size: 1.125rem;
  flex-shrink: 0;
  margin-top: 0.125rem;
}

.page-about__principle-title {
  display: block;
  font-family: var(--font-heading);
  font-size: 1.0625rem;
  color: var(--color-gold-light);
  margin-bottom: 0.25rem;
}

.page-about__principle-desc {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  margin: 0;
  line-height: 1.5;
}

/* 悬停展开的额外文字 */
.page-about__card-extra {
  overflow: hidden;
  max-height: 0;
  opacity: 0;
  transition: max-height 0.4s ease, opacity 0.4s ease, margin 0.3s ease;
  margin-top: 0;
}

.page-about__card--philosophy:hover .page-about__card-extra,
.page-about__card--philosophy:focus-within .page-about__card-extra {
  max-height: 200px;
  opacity: 1;
  margin-top: 1.25rem;
}

.page-about__card-extra-text {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  margin: 0;
  padding-top: 1rem;
  border-top: 1px solid var(--color-border);
}

/* 切换按钮（渐进增强：hover 时自动显示，按钮作为后备） */
.page-about__card-toggle {
  display: none; /* 由 JS 启用，此处仅为结构预留 */
}

/* ---------- 承诺列表 + 斜线分隔 ---------- */
.page-about__commitment-list {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.page-about__commitment-item {
  padding: 1rem 0;
  position: relative;
}

.page-about__commitment-heading {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-gold-light);
  margin: 0 0 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.page-about__commitment-heading::before {
  content: '//';
  color: var(--color-gold-dark);
  font-size: 0.875rem;
  opacity: 0.7;
}

.page-about__commitment-desc {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
  margin: 0 0 0.75rem;
  line-height: 1.5;
}

.page-about__commitment-link {
  font-size: 0.875rem;
  color: var(--color-gold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-speed);
}

.page-about__commitment-link:hover,
.page-about__commitment-link:focus-visible {
  border-bottom-color: var(--color-gold);
  outline: none;
}

/* 斜线分隔符 */
.page-about__commitment-divider {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 1.25rem;
  position: relative;
}

.page-about__slash {
  display: block;
  width: 60%;
  height: 2px;
  background: var(--gradient-gold);
  transform: skewY(-2deg);
  opacity: 0.5;
  border-radius: 1px;
}

/* ---------- 联系卡片 ---------- */
.page-about__contact-card {
  background: var(--color-surface);
  border: 2px solid transparent;
  border-image: var(--gradient-gold) 1;
  border-radius: var(--about-card-radius);
  padding: 2rem 1.5rem;
  width: 100%;
  max-width: 520px;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.25);
}

.page-about__contact-row {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.75rem 0;
  border-bottom: 1px solid var(--color-border);
}

.page-about__contact-row:last-of-type {
  border-bottom: none;
}

.page-about__contact-label {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.page-about__contact-value-wrapper {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.page-about__contact-value {
  font-size: 1.0625rem;
  color: var(--color-gold-light);
  font-family: var(--font-heading);
  word-break: break-all;
}

.page-about__copy-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8125rem;
  padding: 0.25rem 0.75rem;
  background: var(--gradient-gold);
  color: #1A0D0D;
  border: none;
  border-radius: 4px;
  cursor: pointer;
  font-weight: 600;
  transition: opacity var(--transition-speed), transform var(--transition-speed);
  clip-path: polygon(0 0, calc(100% - 6px) 0, 100% 6px, 100% 100%, 0 100%);
}

.page-about__copy-btn:hover,
.page-about__copy-btn:focus-visible {
  opacity: 0.88;
  transform: scale(1.03);
  outline: 2px solid var(--color-gold-light);
  outline-offset: 2px;
}

.page-about__contact-note {
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  margin: 1rem 0 0.5rem;
  line-height: 1.5;
}

.page-about__contact-more {
  display: inline-block;
  font-size: 0.9375rem;
  color: var(--color-gold);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-speed);
  margin-top: 0.75rem;
}

.page-about__contact-more:hover,
.page-about__contact-more:focus-visible {
  border-bottom-color: var(--color-gold);
  outline: none;
}

/* ---------- 桌面端媒体查询 (≥768px) ---------- */
@media (min-width: 768px) {
  .page-about {
    padding: 2rem 2rem 4rem;
  }

  .page-about__hero {
    flex-direction: row;
    align-items: center;
    gap: 3rem;
  }

  .page-about__hero-text {
    order: 1;
    flex: 1 1 55%;
  }

  .page-about__hero-title {
    font-size: 4.5rem;
  }

  .page-about__hero-desc {
    font-size: 1.125rem;
  }

  .page-about__hero-image {
    order: 2;
    flex: 0 0 auto;
    max-width: 500px;
  }

  .page-about__section-body {
    flex-direction: row;
    align-items: flex-start;
    gap: 3rem;
  }

  .page-about__section-body--centered {
    justify-content: center;
  }

  .page-about__card--philosophy {
    flex: 1 1 65%;
    padding: 2rem;
  }

  .page-about__section-figure {
    flex: 0 0 auto;
    max-width: 300px;
    margin: 0;
  }

  .page-about__commitment-list {
    flex: 1 1 65%;
    gap: 0.5rem;
  }

  .page-about__commitment-item {
    padding: 1.25rem 0;
  }

  .page-about__commitment-divider {
    height: 0.75rem;
  }

  .page-about__contact-card {
    padding: 2.5rem 2rem;
  }

  .page-about__contact-row {
    flex-direction: row;
    align-items: center;
    gap: 1.5rem;
  }

  .page-about__contact-label {
    min-width: 6em;
    font-size: 0.875rem;
  }

  .page-about__section-number {
    font-size: 3rem;
  }

  .page-about__section-title {
    font-size: 2rem;
  }

  .page-about__breadcrumb {
    font-size: 0.875rem;
  }
}

/* ---------- 大桌面端 (≥1024px) 微调 ---------- */
@media (min-width: 1024px) {
  .page-about {
    padding: 2.5rem 3rem 5rem;
  }

  .page-about__hero-title {
    font-size: 5rem;
  }

  .page-about__section {
    padding-top: 2rem;
  }

  .page-about__section-body {
    gap: 4rem;
  }
}

/* ---------- 极窄屏安全 ---------- */
@media (max-width: 360px) {
  .page-about__hero-title {
    font-size: 2.5rem;
  }

  .page-about__section-number {
    font-size: 2rem;
  }

  .page-about__section-title {
    font-size: 1.375rem;
  }

  .page-about__contact-card {
    padding: 1.25rem 1rem;
  }
}