/* ==========================================================================
   财神棋牌经典版 · Site CSS
   文件位置 /assets/site.css
   涵盖：Reset、设计变量、中文排版、页头、页脚、通用组件
   ========================================================================== */

/* ---------- 设计变量 ---------- */
:root {
  --color-bg: #0B1A33;
  --color-bg-deep: #081425;
  --color-bg-panel: #1A3A5C;
  --color-bg-grad: #0E2A47;
  --color-gold: #D4AF37;
  --color-gold-dark: #B8860B;
  --color-gold-bright: #F1C40F;
  --color-red: #C0392B;
  --color-red-shadow: #7B241C;
  --color-paper: #F5EFE0;
  --color-text: rgba(245, 239, 224, 0.86);
  --color-text-muted: rgba(245, 239, 224, 0.62);

  --font-display: "Noto Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --font-body: "Noto Sans SC", "Heiti SC", "Microsoft YaHei", Arial, sans-serif;

  --container-max: 1200px;
  --card-notch: polygon(0 14px, 14px 0, 100% 0, 100% calc(100% - 14px), calc(100% - 14px) 100%, 0 100%);
  --shadow-float: 0 8px 24px rgba(0, 0, 0, 0.35), 0 2px 6px rgba(0, 0, 0, 0.25);
  --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.28);

  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --dur-fast: 0.18s;
  --dur-base: 0.28s;
  --dur-slow: 0.55s;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    radial-gradient(circle at 18% 22%, rgba(212, 175, 55, 0.05), transparent 32%),
    radial-gradient(circle at 82% 68%, rgba(192, 57, 43, 0.035), transparent 28%),
    repeating-linear-gradient(45deg, rgba(212, 175, 55, 0.018) 0, rgba(212, 175, 55, 0.018) 1px, transparent 1px, transparent 14px);
}

img,
video,
svg,
canvas {
  display: block;
  max-width: 100%;
  height: auto;
}

figure {
  margin: 0;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.3;
  color: var(--color-paper);
}

h1 { font-size: clamp(2.125rem, 5.5vw, 3.375rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.5rem, 3vw, 1.75rem); }
h4 { font-size: 1.25rem; }

p {
  font-size: 0.9375rem;
  line-height: 1.65;
  color: var(--color-text);
}

small,
.text-micro {
  font-size: 0.75rem;
}

.text-caption {
  font-size: 0.875rem;
}

.text-muted {
  color: var(--color-text-muted);
}

a {
  color: var(--color-gold);
  text-decoration: none;
  transition: color var(--dur-fast) ease, background-color var(--dur-fast) ease,
    border-color var(--dur-fast) ease, transform var(--dur-fast) ease;
}

a:hover {
  color: var(--color-gold-bright);
}

:focus {
  outline: 2px solid rgba(212, 175, 55, 0.6);
  outline-offset: 2px;
}

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

::selection {
  background: rgba(212, 175, 55, 0.35);
  color: var(--color-paper);
}

::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--color-bg-deep);
}

::-webkit-scrollbar-thumb {
  background: var(--color-gold-dark);
  border-radius: 6px;
  border: 2px solid var(--color-bg-deep);
}

/* ---------- 容器 ---------- */
.container,
.page-container {
  width: min(100% - clamp(1rem, 4vw, 2.5rem), var(--container-max));
  margin-inline: auto;
}

.page-container {
  padding-block: clamp(2rem, 5vw, 4rem) clamp(3rem, 6vw, 5.5rem);
}

main:focus {
  outline: none;
}

/* ---------- 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 0.5rem 0 0;
  background: linear-gradient(180deg, rgba(8, 20, 37, 0.62) 0%, rgba(8, 20, 37, 0.24) 78%, transparent 100%);
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 300;
  height: 3px;
  width: 0;
  pointer-events: none;
  background: linear-gradient(90deg, var(--color-gold-dark), var(--color-gold) 50%, var(--color-gold-bright));
}

.skip-link {
  position: fixed;
  top: -100%;
  left: 1rem;
  z-index: 400;
  padding: 0.625rem 1.25rem;
  border-radius: 999px;
  background: linear-gradient(135deg, var(--color-gold), var(--color-gold-dark));
  color: var(--color-bg);
  font-weight: 600;
  font-size: 0.875rem;
  transition: top var(--dur-fast) ease;
}

.skip-link:focus {
  top: 1rem;
}

.nav-capsule {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.375rem 0.5rem 0.375rem 0.875rem;
  margin-top: 0.75rem;
  margin-bottom: 0.75rem;
  background: linear-gradient(140deg, rgba(26, 58, 92, 0.94) 0%, rgba(8, 20, 37, 0.96) 100%);
  border: 1px solid rgba(184, 134, 11, 0.5);
  border-radius: 999px;
  box-shadow: var(--shadow-float), inset 0 1px 0 rgba(245, 239, 224, 0.06);
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  flex-shrink: 0;
  border-radius: 999px;
}

.brand-coin {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.5rem;
  height: 2.5rem;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, var(--color-gold-bright), var(--color-gold-dark) 72%);
  color: var(--color-bg);
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.4), inset 0 1px 2px rgba(255, 255, 255, 0.6);
  position: relative;
}

.brand-coin::after {
  content: "";
  position: absolute;
  inset: 4px;
  border: 1px dashed rgba(11, 26, 51, 0.5);
  border-radius: 50%;
}

.brand-copy {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
  white-space: nowrap;
}

.brand-name {
  font-family: var(--font-display);
  font-size: 1.125rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--color-gold);
}

.brand-sub {
  font-size: 0.75rem;
  letter-spacing: 0.14em;
  color: rgba(245, 239, 224, 0.72);
}

.site-nav .nav-list {
  display: flex;
  align-items: center;
  gap: 0.125rem;
  list-style: none;
}

.nav-item a {
  display: inline-block;
  padding: 0.5rem 0.8125rem;
  border-radius: 999px;
  color: var(--color-paper);
  font-size: 0.9375rem;
  letter-spacing: 0.02em;
  transition: background var(--dur-fast) ease, color var(--dur-fast) ease,
    transform var(--dur-fast) ease, box-shadow var(--dur-fast) ease;
}

.nav-item a:hover {
  background: rgba(212, 175, 55, 0.14);
  color: var(--color-gold-bright);
  transform: translateY(-1px);
}

.nav-item a[aria-current="page"] {
  background: linear-gradient(135deg, var(--color-gold-dark) 0%, var(--color-gold) 100%);
  color: var(--color-bg);
}

.nav-item-cta a {
  background: linear-gradient(135deg, var(--color-gold) 0%, var(--color-gold-dark) 100%);
  color: var(--color-bg);
  font-weight: 600;
  box-shadow: 0 4px 12px rgba(123, 36, 28, 0.3);
}

.nav-item-cta a:hover {
  background: linear-gradient(135deg, var(--color-gold-bright) 0%, var(--color-gold) 100%);
  color: var(--color-bg);
}

.nav-toggle {
  display: none;
}

/* ---------- 页头 · 移动端 ---------- */
@media (max-width: 899px) {
  .site-header {
    padding: 0.375rem 0 0;
  }

  .nav-capsule {
    border-radius: 18px;
    padding: 0.375rem 0.5rem 0.375rem 0.75rem;
    margin-top: 0.375rem;
    margin-bottom: 0.375rem;
  }

  .brand-coin {
    width: 2.125rem;
    height: 2.125rem;
    font-size: 1.0625rem;
  }

  .brand-name {
    font-size: 1rem;
  }

  .site-nav {
    position: absolute;
    top: calc(100% + 0.625rem);
    left: 0.5rem;
    right: 0.375rem;
    z-index: 50;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s;
  }

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

  .site-nav .nav-list {
    flex-direction: column;
    gap: 0.25rem;
    padding: 0.625rem;
    background: linear-gradient(160deg, rgba(26, 58, 92, 0.96), rgba(8, 20, 37, 0.98));
    border: 1px solid rgba(184, 134, 11, 0.5);
    border-radius: 16px;
    clip-path: polygon(0 12px, 12px 0, 100% 0, 100% calc(100% - 12px), calc(100% - 12px) 100%, 0 100%);
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.5);
  }

  .nav-item {
    width: 100%;
  }

  .nav-item a {
    display: block;
    width: 100%;
    padding: 0.6875rem 1rem;
    border-radius: 10px;
    border-left: 2px solid transparent;
    font-size: 0.9375rem;
    color: var(--color-paper);
  }

  .nav-item a:hover {
    background: rgba(212, 175, 55, 0.08);
    color: var(--color-gold);
  }

  .nav-item a[aria-current="page"] {
    background: rgba(212, 175, 55, 0.14);
    border-left-color: var(--color-gold);
    color: var(--color-gold);
  }

  .nav-item-cta a {
    margin-top: 0.375rem;
    text-align: center;
    background: rgba(212, 175, 55, 0.12);
    border: 1px solid rgba(212, 175, 55, 0.4);
    color: var(--color-gold);
  }

  .nav-toggle {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    padding: 0;
    background: transparent;
    border: 1px solid rgba(212, 175, 55, 0.45);
    border-radius: 12px;
    cursor: pointer;
    flex-shrink: 0;
  }

  .nav-toggle-bar {
    display: block;
    width: 1.125rem;
    height: 2px;
    margin: 2px 0;
    border-radius: 2px;
    background: var(--color-gold);
    transition: transform 0.22s ease, opacity 0.22s ease, background 0.22s ease;
  }

  .nav-toggle:hover .nav-toggle-bar {
    background: var(--color-gold-bright);
  }

  .nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
  }

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

  .nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
  }
}

/* ---------- 页脚 ---------- */
.site-footer {
  position: relative;
  margin-top: 3rem;
  overflow: hidden;
  background:
    radial-gradient(circle at 18% 0%, rgba(212, 175, 55, 0.1), transparent 40%),
    linear-gradient(180deg, var(--color-bg) 0%, var(--color-bg-deep) 100%);
  border-top: 1px solid rgba(184, 134, 11, 0.25);
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: min(80%, 480px);
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-gold) 20%, var(--color-gold) 80%, transparent);
}

.site-footer::after {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: repeating-linear-gradient(-45deg, rgba(212, 175, 55, 0.035) 0, rgba(212, 175, 55, 0.035) 1px, transparent 1px, transparent 12px);
}

.site-footer .container {
  position: relative;
  z-index: 1;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.2fr;
  gap: 2.5rem;
  padding: 3.5rem 0 2.75rem;
  border-bottom: 1px solid rgba(184, 134, 11, 0.18);
}

.footer-brand-col {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.625rem;
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--color-gold);
  transition: color var(--dur-fast) ease;
}

.footer-brand::before {
  content: "財";
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.375rem;
  height: 2.375rem;
  border-radius: 50%;
  background: radial-gradient(circle at 32% 32%, var(--color-gold-bright), var(--color-gold-dark) 72%);
  color: var(--color-bg);
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.35), inset 0 1px 2px rgba(255, 255, 255, 0.5);
}

.footer-brand:hover {
  color: var(--color-gold-bright);
}

.footer-brand-sub {
  margin-top: 0.25rem;
  font-size: 0.8125rem;
  letter-spacing: 0.14em;
  color: rgba(245, 239, 224, 0.55);
}

.footer-trust {
  margin-top: 1rem;
  max-width: 34rem;
  font-size: 0.875rem;
  line-height: 1.7;
  color: rgba(245, 239, 224, 0.68);
}

.footer-col {
  display: flex;
  flex-direction: column;
}

.footer-title {
  font-family: var(--font-display);
  font-size: 1rem;
  letter-spacing: 0.12em;
  color: var(--color-gold);
  margin-bottom: 0.875rem;
  padding-left: 0.875rem;
  border-left: 3px solid var(--color-red);
}

.footer-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-list a {
  color: rgba(245, 239, 224, 0.78);
  font-size: 0.875rem;
  transition: color var(--dur-fast) ease, padding-left var(--dur-fast) ease;
}

.footer-list a:hover {
  color: var(--color-gold);
  padding-left: 0.25rem;
}

.footer-contact-list li {
  font-size: 0.875rem;
  line-height: 1.6;
  color: rgba(245, 239, 224, 0.72);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem 1.5rem;
  padding: 1.25rem 0 1.75rem;
  font-size: 0.8125rem;
  color: rgba(245, 239, 224, 0.48);
}

.footer-copyright,
.footer-icp {
  font-size: 0.8125rem;
  color: rgba(245, 239, 224, 0.48);
}

@media (max-width: 899px) {
  .footer-top {
    grid-template-columns: 1fr;
    gap: 1.75rem;
    padding: 2.5rem 0 1.875rem;
  }

  .footer-col {
    padding-top: 0.25rem;
  }

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    padding-bottom: 1.5rem;
  }
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.375rem;
  border-radius: 999px;
  font-family: var(--font-body);
  font-size: 0.9375rem;
  font-weight: 600;
  line-height: 1.4;
  cursor: pointer;
  border: 1px solid transparent;
  text-decoration: none;
  transition: transform var(--dur-fast) ease, box-shadow var(--dur-fast) ease,
    background var(--dur-fast) ease, color var(--dur-fast) ease, border-color var(--dur-fast) ease;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-gold) 0%, var(--color-gold-dark) 100%);
  color: var(--color-bg);
  box-shadow: 0 4px 14px rgba(123, 36, 28, 0.28);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--color-gold-bright) 0%, var(--color-gold) 100%);
  color: var(--color-bg);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(123, 36, 28, 0.35);
}

.btn-ghost {
  background: transparent;
  border-color: rgba(212, 175, 55, 0.5);
  color: var(--color-gold);
}

.btn-ghost:hover {
  border-color: var(--color-gold);
  background: rgba(212, 175, 55, 0.08);
  color: var(--color-gold-bright);
}

/* ---------- 通用章节 ---------- */
.section {
  padding-block: clamp(2.25rem, 6vw, 4.5rem);
}

.section + .section {
  border-top: 1px solid rgba(184, 134, 11, 0.15);
}

.section-head {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 2rem;
}

.section-titles {
  flex: 1;
  min-width: 0;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-gold-dark);
  padding-left: 0.75rem;
  border-left: 3px solid var(--color-red);
}

.section-title {
  margin: 0.375rem 0 0;
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  line-height: 1.25;
  color: var(--color-gold);
}

.section-note {
  writing-mode: vertical-rl;
  align-self: center;
  flex-shrink: 0;
  font-size: 0.8125rem;
  letter-spacing: 0.1em;
  color: rgba(212, 175, 55, 0.55);
  user-select: none;
}

.divider-slant {
  height: 1px;
  border: 0;
  margin: 2.75rem 0;
  background: linear-gradient(90deg, transparent, rgba(184, 134, 11, 0.55) 18%, rgba(212, 175, 55, 0.8) 50%, rgba(184, 134, 11, 0.55) 82%, transparent);
  transform: rotate(-0.6deg) scaleX(1.015);
}

/* ---------- 卡片 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(16rem, 100%), 1fr));
  gap: 1.25rem;
}

.surface-card {
  position: relative;
  padding: 1.5rem 1.75rem;
  background: linear-gradient(165deg, rgba(26, 58, 92, 0.88) 0%, rgba(14, 42, 71, 0.94) 100%);
  border: 1px solid rgba(184, 134, 11, 0.32);
  border-radius: 14px;
  clip-path: var(--card-notch);
  transition: transform var(--dur-base) var(--ease-out),
    box-shadow var(--dur-base) var(--ease-out),
    border-color var(--dur-base) var(--ease-out);
}

.surface-card:hover {
  transform: translateY(-3px);
  border-color: rgba(212, 175, 55, 0.55);
  box-shadow: var(--shadow-card), 0 0 0 1px rgba(212, 175, 55, 0.25);
}

.surface-card-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--color-paper);
  margin-bottom: 0.5rem;
}

.surface-card-text {
  font-size: 0.875rem;
  line-height: 1.65;
  color: rgba(245, 239, 224, 0.74);
}

/* ---------- 标签与标签页 ---------- */
.tag-chip {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.4375rem 1rem;
  border-radius: 999px;
  background: rgba(26, 58, 92, 0.5);
  border: 1px solid var(--color-gold-dark);
  color: var(--color-paper);
  font-family: var(--font-body);
  font-size: 0.8125rem;
  font-weight: 500;
  cursor: pointer;
  transition: background var(--dur-fast) ease, color var(--dur-fast) ease,
    border-color var(--dur-fast) ease, transform var(--dur-fast) ease;
}

.tag-chip:hover {
  border-color: var(--color-gold);
  color: var(--color-gold-bright);
  transform: translateY(-1px);
}

.tag-chip.is-active,
[role="tab"][aria-selected="true"] {
  background: linear-gradient(135deg, var(--color-gold) 0%, var(--color-gold-dark) 100%);
  border-color: var(--color-gold);
  color: var(--color-bg);
  font-weight: 600;
}

.tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.tab-panel,
[role="tabpanel"] {
  display: block;
}

.tab-panel[hidden],
[role="tabpanel"][hidden] {
  display: none;
}

.tab-panel.is-active,
[role="tabpanel"].is-active {
  animation: tabSlideIn var(--dur-base) var(--ease-out);
}

@keyframes tabSlideIn {
  from {
    opacity: 0;
    transform: translateX(14px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

/* ---------- 数据统计 ---------- */
.stat-block {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.125rem;
  padding: 1.25rem 0.75rem;
  text-align: center;
}

.stat-number {
  font-family: var(--font-display);
  font-size: clamp(1.875rem, 4vw, 2.5rem);
  line-height: 1.1;
  font-weight: 700;
  letter-spacing: 0.02em;
  background: linear-gradient(135deg, var(--color-gold-bright) 0%, var(--color-gold) 45%, var(--color-gold-dark) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.stat-label {
  font-size: 0.875rem;
  letter-spacing: 0.06em;
  color: rgba(245, 239, 224, 0.7);
}

/* ---------- 时间线 ---------- */
.timeline {
  position: relative;
  list-style: none;
  margin: 1rem 0;
  padding: 0 0 0 2rem;
}

.timeline::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.125rem;
  bottom: 0.125rem;
  width: 2px;
  background: linear-gradient(180deg, var(--color-gold) 0%, var(--color-gold-dark) 55%, rgba(184, 134, 11, 0.12) 100%);
}

.timeline-item {
  position: relative;
  margin-bottom: 1.875rem;
}

.timeline-item:last-child {
  margin-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -2rem;
  top: 0.25rem;
  width: 0.625rem;
  height: 0.625rem;
  border-radius: 50%;
  border: 2px solid var(--color-gold);
  background: var(--color-red);
  box-shadow: 0 0 0 4px rgba(192, 57, 43, 0.15);
}

.timeline-title {
  font-family: var(--font-display);
  font-size: 1.0625rem;
  color: var(--color-paper);
  margin-bottom: 0.25rem;
}

.timeline-text {
  font-size: 0.875rem;
  color: rgba(245, 239, 224, 0.7);
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  padding: 0.875rem 0 1.5rem;
  font-size: 0.875rem;
}

.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.breadcrumb li + li::before {
  content: "/";
  color: var(--color-gold-dark);
}

.breadcrumb a {
  color: var(--color-gold);
}

.breadcrumb a:hover {
  color: var(--color-gold-bright);
}

.breadcrumb [aria-current="page"] {
  color: rgba(245, 239, 224, 0.56);
}

/* ---------- 图片容器 ---------- */
.img-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border-radius: 12px;
  border: 1px solid rgba(184, 134, 11, 0.35);
  background: linear-gradient(145deg, rgba(26, 58, 92, 0.6) 0%, rgba(8, 20, 37, 0.82) 100%);
  padding-top: 75%;
}

.img-frame > img,
.img-frame > picture > img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s var(--ease-out);
}

.img-frame:hover > img,
.img-frame:hover > picture > img {
  transform: scale(1.025);
}

.img-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background: linear-gradient(180deg, transparent 55%, rgba(8, 20, 37, 0.65) 100%);
}

.img-frame figcaption {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 2;
  padding: 0.875rem 1rem 0.625rem;
  background: linear-gradient(0deg, rgba(8, 20, 37, 0.92) 0%, rgba(8, 20, 37, 0.45) 75%, transparent 100%);
  color: var(--color-paper);
  font-size: 0.8125rem;
  letter-spacing: 0.04em;
}

@supports (aspect-ratio: 4 / 3) {
  .img-frame {
    padding-top: 0;
    aspect-ratio: 4 / 3;
  }
}

/* ---------- 章节序号 ---------- */
.chapter-index {
  position: fixed;
  right: 0.875rem;
  bottom: 0.875rem;
  z-index: 60;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.3125rem 0.75rem;
  border-radius: 999px;
  background: rgba(11, 26, 51, 0.84);
  border: 1px solid rgba(184, 134, 11, 0.45);
  color: var(--color-gold);
  font-family: var(--font-display);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.3);
  pointer-events: none;
}

@media (max-width: 899px) {
  .chapter-index {
    display: none;
  }
}

/* ---------- 显现动效 ---------- */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity var(--dur-slow) var(--ease-out),
    transform var(--dur-slow) var(--ease-out);
}

[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ---------- 辅助类 ---------- */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ---------- 减少动态 ---------- */
@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;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .surface-card:hover {
    transform: none;
  }

  .nav-item a:hover {
    transform: none;
  }

  .btn-primary:hover,
  .btn-ghost:hover {
    transform: none;
  }

  .tag-chip:hover {
    transform: none;
  }

  .img-frame:hover > img,
  .img-frame:hover > picture > img {
    transform: none;
  }
}