:root {
  --color-surface: #fdfdfd;
  --color-surface-alt: #f3f3f3;
  --color-surface-deep: #e5e5e4;
  --color-ink: #37342f;
  --color-ink-soft: #656058;
  --color-ink-muted: #827c73;
  --color-line: #d9d9d8;
  --color-primary: #9f690e;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #f0e8dc;
  --color-accent: #0b76d5;
  --color-accent-ink: #ffffff;
  --color-highlight: #d1e5f6;
  --color-focus: #0072d6;
  --color-contrast-surface: #282012;
  --color-contrast-ink: #e7e6e4;
  --color-contrast-line: #524c40;
  --color-contrast-accent: #1289f2;
  --overlay-scrim: linear-gradient(180deg, rgba(40, 32, 18, 0.35) 0%, rgba(40, 32, 18, 0.72) 55%, rgba(40, 32, 18, 0.92) 100%);
  --font-heading: "Source Han Sans SC", "Noto Sans SC", SimHei, "Microsoft YaHei", sans-serif;
  --font-body: "PingFang SC", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 9.3px;
  --text-sm: 13.9px;
  --text-base: 17px;
  --text-lg: 25.5px;
  --text-xl: 38.2px;
  --text-2xl: 57.4px;
  --text-3xl: 86.1px;
  --text-4xl: 129.1px;
  --text-display: clamp(51px, 10.5vw, 135px);
  --text-figure: clamp(43px, 7.6vw, 97px);
  --weight-heading: 886;
  --weight-body: 400;
  --leading-body: 1.67;
  --leading-heading: 1.18;
  --tracking-heading: -0.028em;
  --radius-sm: 2px;
  --radius-md: 6px;
  --radius-lg: 10px;
  --radius-pill: 999px;
  --border-thin: 2px;
  --border-thick: 3px;
  --shadow-1: 4px 4px 0 #37342f;
  --shadow-2: 8px 8px 0 #37342f;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1120px;
  --measure: 71ch;
  --gutter: 16px;
  --section-y: 65px;
  --section-y-lg: 91px;
}

/* ==========================================================================
   1. 重置与全局基底
   ========================================================================== */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background-color: var(--color-surface);
  background-image: repeating-linear-gradient(
    90deg,
    color-mix(in srgb, var(--color-line) 46%, transparent) 0 1px,
    transparent 1px 72px
  );
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  overflow-x: hidden;
}

[hidden] { display: none !important; }

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

a { color: var(--color-accent); }

button { font: inherit; }

:focus-visible {
  outline: var(--border-thick) solid var(--color-focus);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.visually-hidden {
  position: absolute !important;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* ==========================================================================
   2. 中文排版
   ========================================================================== */
h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0 0 var(--space-2);
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink);
}

h1 { font-size: var(--text-xl); }
h2 { font-size: var(--text-lg); }
h3 { font-size: var(--text-base); }
h4 { font-size: var(--text-sm); }

p {
  margin: 0 0 var(--space-3);
  max-width: var(--measure);
  line-height: var(--leading-body);
}

ul,
ol { margin: 0 0 var(--space-3); padding-left: 1.25em; }

li { line-height: var(--leading-body); }

small { font-size: var(--text-sm); color: var(--color-ink-soft); }

.mono,
.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.01em;
}

/* ==========================================================================
   3. 布局容器与栅格
   ========================================================================== */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }

.section--dark {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.section--dark h1,
.section--dark h2,
.section--dark h3,
.section--dark h4,
.section--dark p { color: var(--color-contrast-ink); }
.section--dark a { color: var(--color-contrast-accent); }

.section__head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: var(--space-2) var(--space-3);
  margin-bottom: var(--space-4);
}
.section__head > * { margin-bottom: 0; }

.grid-12 {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--gutter);
}

.span-3 { grid-column: span 3; }
.span-4 { grid-column: span 4; }
.span-5 { grid-column: span 5; }
.span-6 { grid-column: span 6; }
.span-7 { grid-column: span 7; }
.span-8 { grid-column: span 8; }
.span-9 { grid-column: span 9; }
.span-12 { grid-column: span 12; }

/* ==========================================================================
   4. 斜切面板与错位分隔语言
   ========================================================================== */
.slant-panel {
  position: relative;
  padding: var(--space-8) var(--space-6);
  background: var(--color-primary);
  color: var(--color-primary-ink);
  clip-path: polygon(0 0, 100% 4.5vw, 100% 100%, 0 100%);
  border-radius: var(--radius-lg);
}
.slant-panel h1,
.slant-panel h2,
.slant-panel h3,
.slant-panel p { color: inherit; }

.slant-panel--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
}

.slant-panel--ink {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.rule-offset {
  display: block;
  width: 100%;
  height: var(--border-thin);
  margin: 0;
  border: 0;
  background: var(--color-line);
}
.rule-offset--short { width: min(96px, 30%); }
.rule-offset--primary { background: var(--color-primary); }
.rule-offset--accent { background: var(--color-accent); }
.rule-offset--dark { background: var(--color-contrast-line); }
.rule-offset--offset { margin-left: 24px; }

/* ==========================================================================
   5. 按钮、徽标、编号与卡片
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 13px 22px;
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-ink);
  box-shadow: var(--shadow-1);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  letter-spacing: -0.01em;
  text-decoration: none;
  cursor: pointer;
  transition: transform 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              box-shadow 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              background-color 160ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.btn:hover { transform: translate(-2px, -2px); box-shadow: var(--shadow-2); }
.btn:active { transform: none; box-shadow: var(--shadow-1); }

.btn--primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border-color: var(--color-contrast-surface);
  box-shadow: var(--shadow-1);
}
.btn--accent {
  background: var(--color-accent);
  color: var(--color-accent-ink);
  border-color: var(--color-contrast-surface);
  box-shadow: var(--shadow-1);
}
.btn--ink {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-surface);
  box-shadow: var(--shadow-1);
}
.btn--ghost {
  background: transparent;
  border-color: var(--color-line);
  box-shadow: none;
  color: var(--color-ink-soft);
}
.btn--ghost:hover { box-shadow: var(--shadow-1); color: var(--color-ink); }

.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 9px;
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
  line-height: 1.7;
  white-space: nowrap;
}
.badge--spring { background: var(--color-primary-soft); }
.badge--summer { background: var(--color-accent); color: var(--color-accent-ink); }
.badge--autumn { background: var(--color-primary); color: var(--color-primary-ink); }
.badge--winter { background: var(--color-surface-deep); }
.badge--ink {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
}

.cat-num {
  display: block;
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  font-size: var(--text-figure);
  line-height: 0.86;
  letter-spacing: var(--tracking-heading);
  color: var(--color-primary);
}
.cat-num--accent { color: var(--color-accent); }
.cat-num--ink { color: var(--color-contrast-ink); }

.hard-card {
  padding: var(--space-4);
  background: var(--color-surface);
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-2);
}
.hard-card--alt { background: var(--color-surface-alt); }
.hard-card--ink {
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-surface);
}
.hard-card--ink h1,
.hard-card--ink h2,
.hard-card--ink h3,
.hard-card--ink p { color: var(--color-contrast-ink); }

/* ==========================================================================
   6. 图片容器（展签式）
   ========================================================================== */
.figure {
  position: relative;
  margin: 0;
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-lg);
  background: var(--color-surface-alt);
  box-shadow: var(--shadow-2);
  overflow: hidden;
}

.figure__media {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  background-color: var(--color-surface-deep);
  background-image: linear-gradient(
    135deg,
    color-mix(in srgb, var(--color-accent) 38%, transparent) 0%,
    color-mix(in srgb, var(--color-primary) 52%, transparent) 100%
  );
  transition: transform 320ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.figure__media > img,
.figure__media > svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.figure__scrim {
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
}

.figure__tag {
  position: absolute;
  right: 0;
  bottom: 0;
  z-index: 2;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 11px;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border-top-left-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  letter-spacing: 0.05em;
}

.figure__cap {
  margin: 0;
  padding: var(--space-2) var(--space-3);
  border-top: var(--border-thin) solid var(--color-ink);
  background: var(--color-surface);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
  max-width: none;
}

.figure--zoom { cursor: zoom-in; }
.figure--zoom.is-zoomed { cursor: zoom-out; }
.figure--zoom:hover .figure__media { transform: scale(1.03); }
.figure--zoom.is-zoomed .figure__media { transform: scale(1.35); }

/* ==========================================================================
   7. 时间轴 / 折叠面板 / 编号检索 / 面包屑
   ========================================================================== */
.timeline {
  position: relative;
  margin: 0;
  padding: 0 0 0 var(--space-3);
  list-style: none;
  border-left: var(--border-thin) solid var(--color-line);
}
.timeline__item {
  position: relative;
  padding: 0 0 var(--space-4) var(--space-3);
}
.timeline__item:last-child { padding-bottom: 0; }
.timeline__dot {
  position: absolute;
  left: calc(var(--space-3) * -1 - 6px);
  top: 6px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--color-primary);
  border: var(--border-thin) solid var(--color-contrast-surface);
}
.timeline__item--accent .timeline__dot { background: var(--color-accent); }
.timeline__item--active .timeline__dot { background: var(--color-contrast-accent); }

.collapse {
  border: var(--border-thin) solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  overflow: hidden;
}
.collapse + .collapse { margin-top: calc(var(--border-thin) * -1); }
.collapse__head {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  width: 100%;
  padding: 12px 16px;
  border: 0;
  background: transparent;
  color: var(--color-ink);
  text-align: left;
  cursor: pointer;
  transition: background-color 160ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.collapse__head:hover { background: var(--color-surface-alt); }
.collapse__body {
  padding: var(--space-2) 16px var(--space-3);
  border-top: var(--border-thin) solid var(--color-line);
  background: var(--color-surface);
}

.index-search {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: 10px 18px;
  background: var(--color-surface);
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-1);
  transition: background-color 200ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.index-search__input {
  flex: 1 1 auto;
  min-width: 0;
  border: 0;
  background: transparent;
  color: var(--color-ink);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-sm);
  outline: none;
}
.index-search__input::placeholder { color: var(--color-ink-muted); }
.index-search.is-hit { background: var(--color-highlight); }

.is-hit {
  background: var(--color-highlight);
  border-radius: var(--radius-sm);
  box-shadow: inset 0 0 0 var(--border-thin) var(--color-accent);
}

.breadcrumb {
  margin-bottom: var(--space-3);
  font-size: var(--text-sm);
  color: var(--color-ink-soft);
}
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.breadcrumb__item {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.breadcrumb__item:not(:last-child)::after {
  content: "/";
  font-family: var(--font-mono);
  color: var(--color-ink-muted);
}
.breadcrumb__link {
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: var(--border-thin) solid transparent;
}
.breadcrumb__link:hover { border-bottom-color: currentColor; }
.breadcrumb__current { color: var(--color-ink); font-weight: 700; }

/* ==========================================================================
   8. 显现动效协议
   ========================================================================== */
html.js [data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 420ms cubic-bezier(0.22, 0.61, 0.36, 1) var(--reveal-delay, 0ms),
              transform 420ms cubic-bezier(0.22, 0.61, 0.36, 1) var(--reveal-delay, 0ms);
}
html.js [data-reveal].is-revealed {
  opacity: 1;
  transform: none;
}

/* ==========================================================================
   9. 站点头部（悬浮胶囊导航）
   ========================================================================== */
.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 200;
  padding: 12px 20px;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-accent);
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  text-decoration: none;
  transform: translateY(-170%);
  transition: transform 180ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.skip-link:focus { transform: translateY(0); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  padding: var(--space-2) var(--gutter) 0;
}

.site-header::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    var(--color-surface) 34%,
    color-mix(in srgb, var(--color-surface) 74%, transparent) 100%
  );
  opacity: 0;
  pointer-events: none;
  transition: opacity 240ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.site-header[data-scrolled]::before { opacity: 1; }

.header-shell {
  position: relative;
  z-index: 1;
  max-width: var(--container);
  margin-inline: auto;
}

.header-bar {
  position: relative;
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: 10px 12px 10px 16px;
  background: var(--color-surface);
  border: var(--border-thin) solid var(--color-ink);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-1);
  transition: padding 240ms cubic-bezier(0.22, 0.61, 0.36, 1),
              box-shadow 240ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.site-header[data-scrolled] .header-bar {
  padding-block: 6px;
  box-shadow: var(--shadow-2);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  text-decoration: none;
  color: inherit;
}
.brand__glyph {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  flex: 0 0 auto;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  border: var(--border-thin) solid var(--color-contrast-surface);
  border-radius: var(--radius-sm);
  box-shadow: 3px 3px 0 var(--color-contrast-surface);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: 700;
  letter-spacing: 0.02em;
  transform: rotate(-4deg);
  transition: transform 240ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.brand:hover .brand__glyph { transform: rotate(0deg) scale(1.05); }

.brand__text {
  display: grid;
  gap: 1px;
  line-height: 1.08;
}
.brand__name {
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  font-size: var(--text-lg);
  color: var(--color-ink);
}
.brand__note {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}

.site-nav { margin-left: auto; }

.nav-list {
  display: flex;
  align-items: center;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.nav-list a {
  display: block;
  padding: 8px 11px;
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-pill);
  color: var(--color-ink-soft);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  letter-spacing: -0.012em;
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              background-color 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              border-color 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              box-shadow 160ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.nav-list a:hover {
  color: var(--color-ink);
  background: var(--color-surface-alt);
  border-color: var(--color-line);
}
.nav-list a[aria-current="page"] {
  color: var(--color-primary-ink);
  background: var(--color-primary);
  border-color: var(--color-contrast-surface);
  box-shadow: 3px 3px 0 var(--color-contrast-surface);
}

.nav-list__cta { display: none; }

.header-cta {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 9px 16px;
  background: var(--color-accent);
  color: var(--color-accent-ink);
  border: var(--border-thin) solid var(--color-contrast-surface);
  border-radius: var(--radius-pill);
  box-shadow: 3px 3px 0 var(--color-contrast-surface);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  letter-spacing: -0.01em;
  text-decoration: none;
  white-space: nowrap;
  transition: transform 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              box-shadow 160ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.header-cta:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 var(--color-contrast-surface);
}
.header-cta:active { transform: none; box-shadow: 2px 2px 0 var(--color-contrast-surface); }

.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  flex: 0 0 auto;
  padding: 8px 14px;
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  border: var(--border-thin) solid var(--color-contrast-surface);
  border-radius: var(--radius-pill);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  cursor: pointer;
}
.nav-toggle__bars {
  position: relative;
  display: block;
  width: 16px;
  height: 2px;
  background: currentColor;
}
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  content: "";
  position: absolute;
  left: 0;
  width: 16px;
  height: 2px;
  background: currentColor;
  transition: top 220ms cubic-bezier(0.22, 0.61, 0.36, 1),
              transform 220ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.nav-toggle__bars::before { top: -6px; }
.nav-toggle__bars::after { top: 6px; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { top: 0; transform: rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { top: 0; transform: rotate(-45deg); }

.scroll-rail {
  position: relative;
  height: 4px;
  margin: 8px 22px 0;
  background: color-mix(in srgb, var(--color-line) 82%, transparent);
  border-radius: var(--radius-pill);
  overflow: hidden;
}
.scroll-rail__fill {
  display: block;
  width: 0;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-accent) 100%);
}

/* ==========================================================================
   10. 站点页脚（边框式收口）
   ========================================================================== */
.site-footer {
  position: relative;
  margin-top: var(--section-y-lg);
  background: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.footer-bevel {
  height: 56px;
  background: linear-gradient(
    90deg,
    var(--color-primary-soft) 0 25%,
    var(--color-accent) 25% 50%,
    var(--color-primary) 50% 75%,
    var(--color-surface-deep) 75% 100%
  );
  clip-path: polygon(0 0, 100% 0, 100% 46%, 0 100%);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 0.9fr 1.15fr 1.3fr;
  gap: var(--space-6) var(--space-4);
  padding-block: var(--section-y-lg) var(--section-y);
}

.footer-col {
  position: relative;
  padding-left: var(--space-3);
  border-left: var(--border-thin) solid var(--color-contrast-line);
}
.footer-col::before {
  content: "";
  position: absolute;
  left: -3px;
  top: 0;
  width: 4px;
  height: 22px;
  background: var(--color-contrast-accent);
}

.brand--footer .brand__name { color: var(--color-contrast-ink); }
.brand--footer .brand__note { color: var(--color-contrast-ink); opacity: 0.7; }

.footer-title {
  margin: 0 0 var(--space-3);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
  letter-spacing: 0.14em;
  color: var(--color-contrast-ink);
}

.season-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 6px;
  margin: var(--space-4) 0 0;
  padding: 0;
  list-style: none;
}
.season-chip {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 9px 10px;
  border: var(--border-thin) solid var(--color-contrast-line);
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: var(--text-sm);
}
.season-chip__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  letter-spacing: 0.06em;
  opacity: 0.75;
}
.season-chip--spring { background: var(--color-primary-soft); color: var(--color-ink); }
.season-chip--summer { background: var(--color-accent); color: var(--color-accent-ink); }
.season-chip--autumn { background: var(--color-primary); color: var(--color-primary-ink); }
.season-chip--winter { background: var(--color-surface-deep); color: var(--color-ink); }

.footer-index {
  display: grid;
  gap: var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
}
.footer-index li {
  display: flex;
  align-items: baseline;
  gap: 10px;
}
.footer-index__num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-lg);
  font-weight: 700;
  color: color-mix(in srgb, var(--color-primary) 58%, var(--color-primary-ink));
}
.footer-index__label {
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  opacity: 0.82;
}

.footer-links {
  display: grid;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}
.footer-links a {
  display: inline-block;
  padding-bottom: 1px;
  color: var(--color-contrast-ink);
  border-bottom: var(--border-thin) solid transparent;
  font-size: var(--text-sm);
  text-decoration: none;
  transition: color 160ms cubic-bezier(0.22, 0.61, 0.36, 1),
              border-color 160ms cubic-bezier(0.22, 0.61, 0.36, 1);
}
.footer-links a:hover,
.footer-links a:focus-visible {
  color: var(--color-contrast-accent);
  border-bottom-color: var(--color-contrast-accent);
}

.footer-contacts {
  display: grid;
  gap: var(--space-2);
  margin: 0;
  padding: 0;
  list-style: none;
}
.footer-contacts li { display: grid; gap: 2px; }
.footer-contacts__key {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.1em;
  color: var(--color-contrast-accent);
}
.footer-contacts__val {
  font-size: var(--text-sm);
  color: var(--color-contrast-ink);
  word-break: break-word;
}

.footer-scale {
  height: 16px;
  border-top: var(--border-thin) solid var(--color-contrast-line);
  background-image: linear-gradient(90deg, var(--color-contrast-line) 0 2px, transparent 2px 100%);
  background-size: 32px 8px;
  background-repeat: repeat-x;
}
.footer-scale::after {
  content: "";
  display: block;
  height: 6px;
  margin-top: 4px;
  background-image: linear-gradient(90deg, var(--color-contrast-line) 0 2px, transparent 2px 100%);
  background-size: 32px 6px;
  background-repeat: repeat-x;
  background-position: 16px 0;
}

.footer-legal {
  border-top: var(--border-thin) solid var(--color-contrast-line);
}
.footer-legal__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  padding-block: var(--space-3);
}
.footer-legal__item {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: var(--text-xs);
  letter-spacing: 0.04em;
  color: var(--color-contrast-ink);
  opacity: 0.78;
}

/* ==========================================================================
   11. 响应式
   ========================================================================== */
@media (max-width: 1080px) {
  .brand__note { display: none; }
  .brand__name { font-size: var(--text-base); }
  .nav-list a { padding: 8px 9px; font-size: var(--text-sm); }
}

@media (max-width: 992px) {
  .header-bar {
    gap: var(--space-2);
    padding: 8px 10px 8px 12px;
    border-radius: var(--radius-lg);
  }
  .site-header[data-scrolled] .header-bar { padding-block: 6px; }

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

  .header-cta {
    padding: 8px 12px;
    font-size: var(--text-xs);
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: calc(100% + var(--space-2));
    margin-left: 0;
    padding: var(--space-2);
    background: var(--color-surface);
    border: var(--border-thin) solid var(--color-ink);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-2);
    display: none;
    max-height: min(72vh, 560px);
    overflow-y: auto;
  }
  .site-nav[data-open] {
    display: block;
    animation: nav-drop 240ms cubic-bezier(0.22, 0.61, 0.36, 1) both;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 4px;
  }
  .nav-list a {
    padding: 12px 14px;
    border-radius: var(--radius-md);
    border-left: var(--border-thick) solid var(--color-line);
    font-size: var(--text-base);
  }
  .nav-list a[aria-current="page"] {
    border-left-color: var(--color-contrast-surface);
    box-shadow: none;
  }
  .nav-list__cta { display: block; }
  .nav-list__cta a {
    background: var(--color-accent);
    color: var(--color-accent-ink);
    border-color: var(--color-contrast-surface);
    border-left-color: var(--color-contrast-surface);
  }

  .slant-panel { padding: var(--space-6) var(--space-4); }
  .slant-panel { clip-path: polygon(0 0, 100% 3.5vw, 100% 100%, 0 100%); }

  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }

  .span-3,
  .span-4,
  .span-5 { grid-column: span 6; }
  .span-7,
  .span-8,
  .span-9 { grid-column: span 12; }
}

@keyframes nav-drop {
  from { opacity: 0; transform: translateY(-10px); }
  to { opacity: 1; transform: none; }
}

@media (max-width: 640px) {
  .header-cta { display: none; }
  .brand__glyph { width: 32px; height: 32px; }

  .scroll-rail { margin-inline: 12px; }

  .footer-bevel { height: 34px; }
  .footer-grid { grid-template-columns: 1fr; gap: var(--space-4); }
  .footer-col { padding-left: var(--space-2); }
  .season-strip { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-legal__inner { flex-direction: column; align-items: flex-start; }

  .grid-12 > [class*="span-"] { grid-column: span 12; }
  .grid-12 { gap: var(--space-2); }
}

@media (max-width: 480px) {
  .nav-toggle__label { display: none; }
  .brand__name { font-size: var(--text-sm); }
}

/* ==========================================================================
   12. 减弱动效
   ========================================================================== */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }

  html.js [data-reveal] {
    opacity: 1 !important;
    transform: none !important;
    transition: none !important;
  }

  .btn:hover,
  .header-cta:hover { transform: none; }

  .figure--zoom:hover .figure__media,
  .figure--zoom.is-zoomed .figure__media { transform: none; }
}