:root {
  --color-surface: #fefefe;
  --color-surface-alt: #f5f5f5;
  --color-surface-deep: #e8e9e8;
  --color-ink: #434c49;
  --color-ink-soft: #67746f;
  --color-ink-muted: #7a8581;
  --color-line: #dcdedd;
  --color-primary: #557d6e;
  --color-primary-ink: #ffffff;
  --color-primary-soft: #e6ecea;
  --color-accent: #1f845e;
  --color-accent-ink: #ffffff;
  --color-highlight: #d6e8e1;
  --color-focus: #16835a;
  --color-contrast-surface: #161a18;
  --color-contrast-ink: #e4e7e6;
  --color-contrast-line: #434745;
  --color-contrast-accent: #31ce93;
  --overlay-scrim: linear-gradient(180deg, rgba(22, 26, 24, 0.35) 0%, rgba(22, 26, 24, 0.72) 55%, rgba(22, 26, 24, 0.92) 100%);
  --font-heading: STZhongsong, "Source Han Serif SC", "Songti SC", SimSun, serif;
  --font-body: "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: ui-monospace, Menlo, Consolas, monospace;
  --text-xs: 8.7px;
  --text-sm: 13.1px;
  --text-base: 16px;
  --text-lg: 24.0px;
  --text-xl: 36.0px;
  --text-2xl: 54.0px;
  --text-3xl: 81.0px;
  --text-4xl: 121.5px;
  --text-display: clamp(39px, 8.0vw, 102px);
  --text-figure: clamp(32px, 5.7vw, 73px);
  --weight-heading: 461;
  --weight-body: 400;
  --leading-body: 1.76;
  --leading-heading: 1.23;
  --tracking-heading: 0.014em;
  --radius-sm: 0px;
  --radius-md: 0px;
  --radius-lg: 0px;
  --radius-pill: 0px;
  --border-thin: 1px;
  --border-thick: 1px;
  --shadow-1: none;
  --shadow-2: none;
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-6: 48px;
  --space-8: 64px;
  --container: 1240px;
  --measure: 65ch;
  --gutter: 24px;
  --section-y: 155px;
  --section-y-lg: 217px;
}

/* ==========================================================================
   1. 基础重置
   ========================================================================== */
*,
*::before,
*::after { box-sizing: border-box; }

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

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-ink);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: var(--weight-body);
  line-height: var(--leading-body);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body[data-nav-locked] { overflow: hidden; }

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

img { height: auto; }

button,
input,
select,
textarea { font: inherit; color: inherit; }

ul,
ol { margin: 0; padding: 0; list-style: none; }

dl,
dd { margin: 0; }

figure { margin: 0; }

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-family: var(--font-heading);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}

p { margin: 0 0 var(--space-2); }
p:last-child { margin-bottom: 0; }

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 180ms ease;
}
a:hover { color: var(--color-accent); }

hr {
  border: 0;
  border-top: var(--border-thin) solid var(--color-line);
  margin: var(--space-4) 0;
}

::selection {
  background-color: var(--color-highlight);
  color: var(--color-ink);
}

:where(a, button, summary, [tabindex]):focus-visible {
  outline: 2px solid var(--color-focus);
  outline-offset: 3px;
}

/* ==========================================================================
   2. 跳过导航
   ========================================================================== */
.skip-link {
  position: absolute;
  left: var(--space-2);
  top: -120px;
  z-index: 200;
  padding: var(--space-2) var(--space-3);
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  transition: top 160ms ease;
}
.skip-link:focus {
  top: var(--space-2);
  color: var(--color-contrast-accent);
}

/* ==========================================================================
   3. 头部框架
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 90;
  background-color: var(--color-surface);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.header-rail {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: 6px;
  background-image: linear-gradient(180deg, var(--color-primary) 0 120px, var(--color-line) 120px 100%);
  pointer-events: none;
  z-index: 95;
}

.header-inner {
  width: min(100% - 2 * var(--gutter), var(--container));
  margin-inline: auto;
  display: flex;
  align-items: center;
  gap: var(--space-4);
  min-height: 88px;
  padding-block: var(--space-2);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  flex: none;
  color: var(--color-ink);
}
.brand:hover { color: var(--color-ink); }

.brand-mark {
  position: relative;
  flex: none;
  width: 12px;
  height: 36px;
  background-color: var(--color-primary);
}
.brand-mark::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 9px;
  background-color: var(--color-accent);
}

.brand-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.brand-name {
  font-family: var(--font-heading);
  font-size: calc(var(--text-base) * 1.25);
  font-weight: var(--weight-heading);
  letter-spacing: 0.06em;
  line-height: 1.2;
}

.brand-line {
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  letter-spacing: 0.28em;
  color: var(--color-ink-muted);
}

.brand-state {
  margin: 0;
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-soft);
  white-space: nowrap;
}

.state-dot {
  flex: none;
  width: 6px;
  height: 6px;
  background-color: var(--color-accent);
  animation: state-pulse 2.6s ease-in-out infinite;
}

@keyframes state-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.32; }
}

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

.nav-list {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.nav-list a {
  position: relative;
  display: inline-block;
  padding: var(--space-2) calc(var(--space-2) - 4px);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  color: var(--color-ink-soft);
  transition: color 180ms ease;
}

.nav-list a::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 2px;
  height: 14px;
  background-color: var(--color-primary);
  transform: translateY(-50%) scaleY(0);
  transition: transform 200ms ease, background-color 200ms ease;
}

.nav-list a:hover,
.nav-list a[aria-current="page"] { color: var(--color-ink); }

.nav-list a:hover::before,
.nav-list a[aria-current="page"]::before { transform: translateY(-50%) scaleY(1); }

.nav-list a[aria-current="page"]::before { background-color: var(--color-accent); }

.header-utility {
  flex: none;
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: calc(var(--space-2) - 3px) var(--space-3);
  border: var(--border-thin) solid var(--color-line);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  color: var(--color-ink);
  transition: background-color 180ms ease, border-color 180ms ease, color 180ms ease;
}
.header-utility::after {
  content: "\2192";
  font-family: var(--font-mono);
  color: var(--color-accent);
  transition: transform 180ms ease;
}
.header-utility:hover {
  background-color: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-ink);
}
.header-utility:hover::after { transform: translateX(3px); }

.nav-toggle {
  display: none;
  margin-left: auto;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  background-color: transparent;
  border: var(--border-thin) solid var(--color-line);
  color: var(--color-ink);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  cursor: pointer;
}

.nav-toggle-lines {
  position: relative;
  width: 18px;
  height: 12px;
}
.nav-toggle-lines::before,
.nav-toggle-lines::after {
  content: "";
  position: absolute;
  left: 0;
  width: 100%;
  height: 1px;
  background-color: currentColor;
  transition: transform 200ms ease;
}
.nav-toggle-lines::before { top: 0; }
.nav-toggle-lines::after { bottom: 0; }

.site-header[data-open="true"] .nav-toggle-lines::before { transform: translateY(6px) rotate(45deg); }
.site-header[data-open="true"] .nav-toggle-lines::after { transform: translateY(-6px) rotate(-45deg); }

/* ==========================================================================
   4. 页脚 —— 卡片式面板
   ========================================================================== */
.site-footer {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
  padding-block: var(--space-8) var(--space-4);
  margin-top: var(--section-y);
}

.site-footer a { color: var(--color-contrast-ink); }
.site-footer a:hover { color: var(--color-contrast-accent); }

.footer-inner { display: block; }

.footer-masthead {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2) var(--space-4);
  padding-bottom: var(--space-4);
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
}

.footer-brand {
  font-family: var(--font-heading);
  font-size: calc(var(--text-base) * 2);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-contrast-ink);
}
.footer-brand:hover { color: var(--color-contrast-accent); }

.footer-tagline {
  margin: 0;
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: color-mix(in srgb, var(--color-contrast-ink) 66%, transparent);
}

.footer-panels {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1.2fr;
  gap: var(--space-3);
  margin-top: var(--space-6);
}

.footer-panel {
  padding: var(--space-4) var(--space-3);
  background-color: color-mix(in srgb, var(--color-contrast-ink) 6%, transparent);
  border-left: 3px solid var(--color-contrast-line);
}

.footer-panel-title {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  margin: 0 0 var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  font-weight: var(--weight-body);
  letter-spacing: 0.2em;
  color: var(--color-contrast-ink);
}
.footer-panel-title::before {
  content: "";
  flex: none;
  width: 3px;
  height: 13px;
  background-color: var(--color-contrast-accent);
}

.footer-facts {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: var(--space-1) var(--space-2);
  font-size: var(--text-sm);
  margin-bottom: var(--space-3);
}
.footer-facts dt { color: color-mix(in srgb, var(--color-contrast-ink) 58%, transparent); }
.footer-facts dd {
  font-family: var(--font-mono);
  word-break: break-word;
  color: var(--color-contrast-ink);
}

.footer-links {
  display: grid;
  gap: var(--space-2);
  margin-bottom: var(--space-3);
  font-size: var(--text-sm);
}
.footer-links a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  width: fit-content;
  padding-bottom: 2px;
  border-bottom: var(--border-thin) solid var(--color-contrast-line);
  transition: border-color 180ms ease, color 180ms ease;
}
.footer-links a:hover { border-color: var(--color-contrast-accent); }

.footer-panel p {
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 78%, transparent);
  margin-bottom: var(--space-3);
}

.footer-signoff {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-2) var(--space-4);
  margin-top: var(--space-6);
  padding-top: var(--space-3);
  border-top: var(--border-thin) solid var(--color-contrast-line);
  font-size: var(--text-sm);
  color: color-mix(in srgb, var(--color-contrast-ink) 62%, transparent);
}
.footer-signoff p { margin: 0; }
.footer-signoff p:nth-child(2) { font-family: var(--font-mono); letter-spacing: 0.04em; }

/* ==========================================================================
   5. 容器与栅格
   ========================================================================== */
.container {
  width: min(100% - 2 * var(--gutter), var(--container));
  margin-inline: auto;
}

.grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--space-3);
}

.measure { max-width: var(--measure); }

/* ==========================================================================
   6. 章节与底色节奏
   ========================================================================== */
.section { padding-block: var(--section-y); }
.section--lg { padding-block: var(--section-y-lg); }
.section--alt { background-color: var(--color-surface-alt); }
.section--deep { background-color: var(--color-surface-deep); }
.section--contrast {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}

.section--contrast h1,
.section--contrast h2,
.section--contrast h3,
.section--contrast h4,
.section--contrast p,
.section--contrast li,
.section--contrast dt,
.section--contrast dd,
.section--contrast .caption,
.section--contrast .plate-caption { color: var(--color-contrast-ink); }

.section--contrast a { color: var(--color-contrast-accent); }
.section--contrast .expander { border-top-color: var(--color-contrast-line); }
.section--contrast .expander-trigger { color: var(--color-contrast-ink); }
.section--contrast .expander-trigger[aria-expanded="true"] { color: var(--color-contrast-accent); }
.section--contrast .expander-icon { color: var(--color-contrast-accent); }

/* ==========================================================================
   7. 文字与数字
   ========================================================================== */
.display-title {
  font-family: var(--font-heading);
  font-size: var(--text-display);
  font-weight: var(--weight-heading);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
  color: inherit;
  margin: 0;
}

.figure-num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: var(--text-figure);
  line-height: 1;
  letter-spacing: -0.01em;
  font-variant-numeric: tabular-nums;
  color: var(--color-ink);
}
.figure-num--accent { color: var(--color-accent); }

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: 0.02em;
}

.plate-label {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--color-ink-muted);
}
.plate-label::before {
  content: "";
  flex: none;
  width: 18px;
  height: 1px;
  background-color: var(--color-primary);
}

.caption {
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-soft);
}

.marked {
  position: relative;
  padding-left: var(--space-3);
}
.marked::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.15em;
  bottom: 0.15em;
  width: 3px;
  background-color: var(--color-primary);
}
.marked--accent::before { background-color: var(--color-accent); }

/* ==========================================================================
   8. 图片容器与展签
   ========================================================================== */
.media-frame {
  position: relative;
  overflow: hidden;
  background-color: var(--color-surface-deep);
  aspect-ratio: 16 / 9;
}

.media-frame > img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: saturate(0.32) contrast(1.06);
}

.media-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background-color: color-mix(in srgb, var(--color-primary) 58%, transparent);
  mix-blend-mode: multiply;
  pointer-events: none;
  z-index: 1;
}

.media-frame[data-overlay]::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--overlay-scrim);
  pointer-events: none;
  z-index: 1;
}

.media-label {
  position: absolute;
  left: var(--space-4);
  right: var(--space-4);
  bottom: var(--space-4);
  z-index: 2;
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-contrast-ink);
}

.plate { display: grid; gap: var(--space-2); }

.plate-caption {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-soft);
}
.plate-caption::before {
  content: "";
  flex: none;
  width: 20px;
  height: 1px;
  background-color: var(--color-primary);
}

/* ==========================================================================
   9. 按钮与链接
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: var(--space-2) var(--space-3);
  border: var(--border-thin) solid transparent;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: background-color 180ms ease, color 180ms ease, border-color 180ms ease;
}

.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn--primary:hover {
  background-color: var(--color-accent);
  color: var(--color-accent-ink);
}

.btn--ghost {
  background-color: transparent;
  border-color: var(--color-line);
  color: var(--color-ink);
}
.btn--ghost:hover {
  background-color: var(--color-primary-soft);
  border-color: var(--color-primary);
  color: var(--color-ink);
}

.btn--dark {
  background-color: var(--color-contrast-surface);
  color: var(--color-contrast-ink);
}
.btn--dark:hover { color: var(--color-contrast-accent); }

.link-quiet {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding-bottom: 2px;
  border-bottom: var(--border-thin) solid var(--color-line);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-ink-soft);
  transition: color 180ms ease, border-color 180ms ease;
}
.link-quiet::after {
  content: "\2192";
  font-family: var(--font-mono);
  color: var(--color-accent);
}
.link-quiet:hover {
  color: var(--color-ink);
  border-color: var(--color-primary);
}

.site-footer .link-quiet {
  color: var(--color-contrast-ink);
  border-color: var(--color-contrast-line);
}
.site-footer .link-quiet:hover {
  color: var(--color-contrast-accent);
  border-color: var(--color-contrast-accent);
}

/* ==========================================================================
   10. 面包屑
   ========================================================================== */
.breadcrumb {
  font-size: var(--text-sm);
  letter-spacing: 0.04em;
  color: var(--color-ink-muted);
}
.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
}
.breadcrumb li {
  display: inline-flex;
  align-items: center;
}
.breadcrumb li::after {
  content: "/";
  margin-inline: var(--space-1);
  color: var(--color-line);
}
.breadcrumb li:last-child::after { content: none; }
.breadcrumb a { color: var(--color-ink-soft); }
.breadcrumb a:hover { color: var(--color-accent); }

/* ==========================================================================
   11. 可展开档案组
   ========================================================================== */
.expander { border-top: var(--border-thin) solid var(--color-line); }

.expander-trigger {
  display: flex;
  align-items: baseline;
  gap: var(--space-2);
  width: 100%;
  padding: var(--space-3) 0;
  background: none;
  border: 0;
  text-align: left;
  cursor: pointer;
  font-family: var(--font-heading);
  font-size: var(--text-lg);
  font-weight: var(--weight-heading);
  letter-spacing: var(--tracking-heading);
  color: var(--color-ink-soft);
  transition: color 180ms ease;
}
.expander-trigger:hover { color: var(--color-ink); }
.expander-trigger[aria-expanded="true"] { color: var(--color-ink); }

.expander-icon {
  margin-left: auto;
  font-family: var(--font-mono);
  font-size: var(--text-base);
  color: var(--color-primary);
  transition: transform 220ms ease;
}
.expander-trigger[aria-expanded="true"] .expander-icon { transform: rotate(45deg); }

.expander-panel {
  display: grid;
  grid-template-rows: 0fr;
  opacity: 0;
  transition: grid-template-rows 260ms ease, opacity 200ms ease;
}
.expander-panel[data-open="true"] {
  grid-template-rows: 1fr;
  opacity: 1;
}
.expander-body {
  overflow: hidden;
  min-height: 0;
}
.expander-body > *:last-child { padding-bottom: var(--space-4); }

/* ==========================================================================
   12. 标签切换
   ========================================================================== */
.tab-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-1);
  border-bottom: var(--border-thin) solid var(--color-line);
}

.tab {
  padding: var(--space-2) var(--space-3);
  background: none;
  border: 0;
  border-bottom: 2px solid transparent;
  font-family: var(--font-body);
  font-size: var(--text-sm);
  letter-spacing: 0.08em;
  color: var(--color-ink-muted);
  cursor: pointer;
  transition: color 180ms ease, background-color 180ms ease, border-color 180ms ease;
}
.tab:hover {
  color: var(--color-ink);
  background-color: var(--color-surface-alt);
}
.tab[aria-selected="true"] {
  color: var(--color-ink);
  background-color: var(--color-primary-soft);
  border-bottom-color: var(--color-accent);
}

.tab-panel { padding-top: var(--space-4); }
.tab-panel[hidden] { display: none; }

/* ==========================================================================
   13. 横向滚动条带
   ========================================================================== */
.band { position: relative; }

.band-track {
  display: flex;
  gap: var(--space-3);
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  scroll-padding-inline: var(--space-3);
  padding-bottom: var(--space-3);
  -webkit-overflow-scrolling: touch;
  scrollbar-width: thin;
  scrollbar-color: var(--color-primary) var(--color-line);
}
.band-track::-webkit-scrollbar { height: 4px; }
.band-track::-webkit-scrollbar-track { background-color: var(--color-line); }
.band-track::-webkit-scrollbar-thumb { background-color: var(--color-primary); }

.band-item {
  flex: 0 0 min(78vw, 320px);
  scroll-snap-align: start;
}

.band-fade {
  position: absolute;
  top: 0;
  bottom: var(--space-3);
  width: 56px;
  pointer-events: none;
  z-index: 2;
}
.band-fade--start {
  left: 0;
  background: linear-gradient(90deg, var(--color-surface), transparent);
}
.band-fade--end {
  right: 0;
  background: linear-gradient(270deg, var(--color-surface), transparent);
}

.band--dark .band-track { scrollbar-color: var(--color-contrast-accent) var(--color-contrast-line); }
.band--dark .band-track::-webkit-scrollbar-track { background-color: var(--color-contrast-line); }
.band--dark .band-track::-webkit-scrollbar-thumb { background-color: var(--color-contrast-accent); }
.band--dark .band-fade--start { background: linear-gradient(90deg, var(--color-contrast-surface), transparent); }
.band--dark .band-fade--end { background: linear-gradient(270deg, var(--color-contrast-surface), transparent); }

.band--alt .band-fade--start { background: linear-gradient(90deg, var(--color-surface-alt), transparent); }
.band--alt .band-fade--end { background: linear-gradient(270deg, var(--color-surface-alt), transparent); }

/* ==========================================================================
   14. 赛季刻度（页面阶段使用）
   ========================================================================== */
.season-rail {
  position: relative;
  padding-left: var(--space-3);
  border-left: var(--border-thin) solid var(--color-line);
}

.season-rail-marker {
  position: relative;
  display: block;
  padding: var(--space-2) 0;
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  letter-spacing: 0.06em;
  color: var(--color-ink-muted);
  transition: color 200ms ease;
}
.season-rail-marker::before {
  content: "";
  position: absolute;
  top: 50%;
  left: calc(-1 * var(--space-3) - 1px);
  width: 9px;
  height: 1px;
  background-color: var(--color-line);
  transition: width 220ms ease, background-color 220ms ease, height 220ms ease;
}
.season-rail-marker:hover { color: var(--color-ink); }
.season-rail-marker[aria-current="true"] { color: var(--color-ink); }
.season-rail-marker[aria-current="true"]::before {
  width: 24px;
  height: 2px;
  background-color: var(--color-accent);
}

/* ==========================================================================
   15. 显现动效
   ========================================================================== */
html[data-js="on"] [data-reveal] {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 460ms ease, transform 460ms ease;
}
html[data-js="on"] [data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ==========================================================================
   16. 响应式
   ========================================================================== */
@media (max-width: 1120px) {
  .brand-state { display: none; }
}

@media (max-width: 900px) {
  .header-inner {
    min-height: 72px;
    gap: var(--space-2);
  }

  .header-utility { display: none; }

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

  .site-nav {
    position: fixed;
    inset: 0 0 0 auto;
    width: min(86vw, 400px);
    margin: 0;
    padding: 104px var(--space-3) var(--space-6);
    background-color: var(--color-surface);
    border-left: var(--border-thin) solid var(--color-line);
    overflow-y: auto;
    transform: translateX(100%);
    opacity: 0;
    visibility: hidden;
    transition: transform 260ms ease, opacity 200ms ease, visibility 0s linear 260ms;
    z-index: 85;
  }

  .site-nav[data-open="true"] {
    transform: translateX(0);
    opacity: 1;
    visibility: visible;
    transition: transform 260ms ease, opacity 200ms ease, visibility 0s;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
  }
  .nav-list a {
    padding: var(--space-3);
    border-bottom: var(--border-thin) solid var(--color-line);
    font-size: var(--text-base);
  }
  .nav-list a::before { height: 56%; }

  .footer-panels { grid-template-columns: 1fr 1fr; }
  .footer-panel:first-child { grid-column: 1 / -1; }

  .section { padding-block: calc(var(--section-y) * 0.62); }
  .section--lg { padding-block: calc(var(--section-y-lg) * 0.62); }

  .grid { gap: var(--space-2); }
}

@media (max-width: 640px) {
  .header-rail { width: 3px; background-image: linear-gradient(180deg, var(--color-primary) 0 72px, var(--color-line) 72px 100%); }

  .brand-name { font-size: var(--text-base); }
  .brand-line { letter-spacing: 0.2em; }

  .footer-panels { grid-template-columns: 1fr; }
  .footer-panel:first-child { grid-column: auto; }
  .footer-signoff { flex-direction: column; align-items: flex-start; }

  .caption,
  .plate-caption { font-size: var(--text-base); }

  .expander-trigger { font-size: var(--text-lg); }
}

/* ==========================================================================
   17. 减少动效
   ========================================================================== */
@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[data-js="on"] [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .band-track { scroll-behavior: auto; }
}