:root {
  --color-deep: #0A2342;
  --color-gold: #C9A227;
  --color-gold-light: #E5C76B;
  --color-gray: #F4F4F4;
  --color-white: #FFFFFF;
  --color-peacock: #1B6A8F;
  --color-terrace: #4B8B7A;
  --color-ink: #111111;
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", serif;
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --space-unit: 8px;
  --space-2: calc(var(--space-unit) * 2);
  --space-3: calc(var(--space-unit) * 3);
  --space-4: calc(var(--space-unit) * 4);
  --space-6: calc(var(--space-unit) * 6);
  --space-8: calc(var(--space-unit) * 8);
  --space-12: calc(var(--space-unit) * 12);
  --content-max: 1200px;
  --shadow-card: 0 4px 16px rgba(10, 35, 66, 0.06);
  --transition: 200ms ease;
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.75;
  color: var(--color-ink);
  background: var(--color-white);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

body, h1, h2, h3, h4, h5, h6, p, ul, ol, dl, dd, figure {
  margin: 0;
}

ul, ol {
  list-style: none;
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  font-size: inherit;
  color: inherit;
  border: none;
  background: none;
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 3px;
}

/* ==========================================
   无障碍跳转
   ========================================== */
.skip-link {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1000;
  padding: 10px 20px;
  background: var(--color-gold);
  color: var(--color-deep);
  font-weight: 700;
  font-size: 14px;
  letter-spacing: 0.06em;
  transform: translateY(-100%);
  transition: transform var(--transition);
}

.skip-link:focus-visible {
  transform: translateY(0);
}

/* ==========================================
   页头
   ========================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background:
    repeating-linear-gradient(
      180deg,
      transparent 0,
      transparent 14px,
      rgba(201, 162, 39, 0.04) 14px,
      rgba(201, 162, 39, 0.04) 15px
    ),
    linear-gradient(180deg, #0A2342 0%, #0C2B52 100%);
  border-bottom: 1px solid rgba(201, 162, 39, 0.35);
}

.site-header__progress {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light));
  z-index: 10;
}

.site-header__top {
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: 36px;
  padding: 0 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.07);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.62);
}

.site-header__top-note {
  color: rgba(229, 199, 107, 0.78);
}

.site-header__top-divider {
  width: 1px;
  height: 12px;
  background: rgba(201, 162, 39, 0.4);
}

.site-header__top-loc {
  letter-spacing: 0.12em;
}

.site-header__main {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  padding: 0 24px;
}

.site-header__meta {
  position: absolute;
  top: 50%;
  right: 28px;
  transform: translateY(-50%);
  writing-mode: vertical-rl;
  font-size: 11px;
  letter-spacing: 0.3em;
  color: rgba(201, 162, 39, 0.6);
  border-right: 1px solid rgba(201, 162, 39, 0.3);
  padding-right: 8px;
  white-space: nowrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
}

.brand__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid var(--color-gold);
  border-radius: 2px;
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-gold);
  background: rgba(201, 162, 39, 0.08);
}

.brand__copy {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand__name {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: #FFFFFF;
  letter-spacing: 0.14em;
}

.brand__sub {
  font-size: 10px;
  letter-spacing: 0.3em;
  color: rgba(229, 199, 107, 0.85);
  text-transform: uppercase;
  margin-top: 2px;
}

/* 移动端汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(201, 162, 39, 0.55);
  border-radius: 2px;
  background: transparent;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--color-gold);
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* 主导航 */
.main-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}

.main-nav__link {
  position: relative;
  display: inline-block;
  padding: 8px 10px;
  margin: 0 4px;
  font-size: 15px;
  letter-spacing: 0.1em;
  color: rgba(255, 255, 255, 0.88);
  transition: color var(--transition);
  white-space: nowrap;
}

.main-nav__link::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 2px;
  height: 1px;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

.main-nav__link:hover,
.main-nav__link:focus-visible {
  color: var(--color-gold-light);
}

.main-nav__link:hover::after,
.main-nav__link:focus-visible::after,
.main-nav__link[aria-current="page"]::after {
  transform: scaleX(1);
}

.main-nav__link[aria-current="page"] {
  color: var(--color-gold-light);
  font-weight: 600;
}

/* 移动端导航面板 */
@media (max-width: 900px) {
  .site-header__meta {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px 24px 20px;
    background:
      repeating-linear-gradient(
        180deg,
        transparent 0,
        transparent 12px,
        rgba(201, 162, 39, 0.05) 12px,
        rgba(201, 162, 39, 0.05) 13px
      ),
      #0A2342;
    border-bottom: 1px solid rgba(201, 162, 39, 0.35);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.2);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity var(--transition), transform var(--transition), visibility var(--transition);
  }

  .main-nav[data-open] {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .main-nav__link {
    padding: 14px 4px;
    margin: 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    font-size: 16px;
  }

  .main-nav__link:last-child {
    border-bottom: none;
  }

  .main-nav__link::after {
    left: 0;
    bottom: 0;
  }
}

@media (max-width: 640px) {
  .site-header__top {
    display: none;
  }

  .site-header__main {
    min-height: 60px;
    padding: 0 16px;
  }

  .brand__mark {
    width: 36px;
    height: 36px;
    font-size: 18px;
  }

  .brand__name {
    font-size: 19px;
  }

  .brand__sub {
    font-size: 9px;
  }
}

/* ==========================================
   页脚
   ========================================== */
.site-footer {
  position: relative;
  background:
    repeating-linear-gradient(
      180deg,
      transparent 0,
      transparent 16px,
      rgba(201, 162, 39, 0.04) 16px,
      rgba(201, 162, 39, 0.04) 17px
    ),
    linear-gradient(180deg, #0A2342 0%, #081A33 100%);
  border-top: 1px solid rgba(201, 162, 39, 0.4);
  color: rgba(255, 255, 255, 0.8);
}

.site-footer__inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr 1fr;
  gap: 48px;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 64px 24px 48px;
}

.site-footer__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.site-footer__note {
  margin-top: 24px;
  font-size: 13px;
  line-height: 1.9;
  color: rgba(255, 255, 255, 0.55);
  max-width: 300px;
}

.site-footer__seal {
  display: inline-block;
  margin-top: 32px;
  writing-mode: vertical-rl;
  font-size: 11px;
  letter-spacing: 0.35em;
  color: rgba(229, 199, 107, 0.45);
  border-right: 1px solid rgba(201, 162, 39, 0.3);
  padding-right: 10px;
}

.site-footer__section {
  min-width: 0;
}

.site-footer__title {
  font-family: var(--font-serif);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.18em;
  color: var(--color-gold-light);
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(201, 162, 39, 0.25);
  margin-bottom: 18px;
}

.site-footer__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.site-footer__list--meta {
  gap: 16px;
}

.site-footer__item {
  font-size: 13px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.6);
}

.site-footer__link {
  position: relative;
  display: inline-block;
  font-size: 13px;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.68);
  transition: color var(--transition);
}

.site-footer__link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 1px;
  background: var(--color-gold);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition);
}

.site-footer__link:hover,
.site-footer__link:focus-visible {
  color: var(--color-gold-light);
}

.site-footer__link:hover::after,
.site-footer__link:focus-visible::after {
  transform: scaleX(1);
}

.site-footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 20px 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 12px;
  letter-spacing: 0.08em;
  color: rgba(255, 255, 255, 0.4);
}

@media (max-width: 900px) {
  .site-footer__inner {
    grid-template-columns: repeat(2, 1fr);
    gap: 36px;
    padding: 48px 24px 36px;
  }
}

@media (max-width: 640px) {
  .site-footer__inner {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .site-footer__bottom {
    flex-direction: column;
    text-align: center;
  }
}

/* ==========================================
   布局工具
   ========================================== */
.page-container {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 24px;
}

.main-content {
  flex: 1;
}

.page-section {
  padding: 96px 0;
}

@media (max-width: 640px) {
  .page-section {
    padding: 64px 0;
  }
}

.section-head {
  margin-bottom: 48px;
  max-width: 720px;
}

.section-title {
  font-family: var(--font-serif);
  font-size: 40px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--color-deep);
  letter-spacing: 0.06em;
}

.section-subtitle {
  margin-top: 16px;
  font-size: 15px;
  line-height: 1.8;
  color: #666;
}

@media (max-width: 640px) {
  .section-title {
    font-size: 28px;
  }
}

.grid-2col {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 48px;
}

.grid-3col {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 40px;
}

@media (max-width: 900px) {
  .grid-2col,
  .grid-3col {
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
  }
}

@media (max-width: 640px) {
  .grid-2col,
  .grid-3col {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 13px;
  letter-spacing: 0.06em;
  color: #888;
  margin-bottom: 32px;
}

.breadcrumb__link {
  color: var(--color-peacock);
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), color var(--transition);
}

.breadcrumb__link:hover,
.breadcrumb__link:focus-visible {
  color: var(--color-deep);
  border-color: var(--color-gold);
}

.breadcrumb__sep {
  color: var(--color-gold);
  margin: 0 4px;
}

.breadcrumb__item[aria-current="page"] {
  color: var(--color-deep);
  font-weight: 600;
}

/* ==========================================
   展签组件
   ========================================== */
.exhibit-label {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.28em;
  color: var(--color-peacock);
  text-transform: uppercase;
}

.exhibit-label::before {
  content: "";
  width: 36px;
  height: 1px;
  background: var(--color-gold);
  flex-shrink: 0;
}

.exhibit-caption {
  border-left: 2px solid var(--color-gold);
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.9;
  color: #666;
}

.exhibit-card {
  position: relative;
  background: var(--color-gray);
  border: 1px solid rgba(10, 35, 66, 0.06);
  border-top: 3px solid var(--color-gold);
  padding: 32px;
  box-shadow: var(--shadow-card);
  transition: transform var(--transition), box-shadow var(--transition);
}

.exhibit-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 28px rgba(10, 35, 66, 0.1);
}

.exhibit-card__index {
  font-family: var(--font-serif);
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--color-gold);
}

.exhibit-card__title {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-deep);
  margin: 12px 0 8px;
}

.exhibit-card__text {
  font-size: 14px;
  line-height: 1.85;
  color: #555;
}

/* ==========================================
   按钮
   ========================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 32px;
  border-radius: 0;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.12em;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition), transform var(--transition);
}

.btn:hover,
.btn:focus-visible {
  transform: translateY(-1px);
}

.btn--primary {
  background: var(--color-gold);
  border-color: var(--color-gold);
  color: var(--color-deep);
}

.btn--primary:hover,
.btn--primary:focus-visible {
  background: var(--color-gold-light);
  border-color: var(--color-gold-light);
}

.btn--ghost {
  border-color: var(--color-deep);
  color: var(--color-deep);
  background: transparent;
}

.btn--ghost:hover,
.btn--ghost:focus-visible {
  background: var(--color-deep);
  color: #FFFFFF;
}

.btn--dark {
  background: var(--color-deep);
  border-color: var(--color-gold);
  color: var(--color-gold-light);
}

.btn--dark:hover,
.btn--dark:focus-visible {
  background: #0C2B52;
  color: var(--color-gold-light);
}

/* ==========================================
   图片容器（页面阶段填充占位）
   ========================================== */
.media-frame {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  background:
    linear-gradient(135deg, rgba(201, 162, 39, 0.12), transparent 30%),
    var(--color-deep);
  aspect-ratio: 4 / 3;
  overflow: hidden;
}

.media-frame::before {
  content: "";
  position: absolute;
  inset: 12px;
  border: 1px solid rgba(201, 162, 39, 0.45);
  z-index: 1;
  pointer-events: none;
}

.media-frame--wide {
  aspect-ratio: 16 / 9;
}

.media-frame--portrait {
  aspect-ratio: 3 / 4;
}

/* 装饰分隔线 */
.divider-line {
  display: block;
  width: 56px;
  height: 2px;
  background: var(--color-gold);
  margin: 24px 0;
}

/* ==========================================
   动效与无障碍
   ========================================== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}